ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 1 of 33
Member of the Family
Applications
Low voltage, high density systems with
Intermediate Bus Architectures (IBA)
Point-of-load regulators for high performance DSP,
FPGA, ASIC, and microprocessor applications
Desktops, servers, and portable computing
Broadband, networking, optical, and
communications systems
Active memory bus terminators
Benefits
Integrates digital power conversion with intelligent
power management
Eliminates the need for external power
management components
Completely programmable via industry-standard
I2C communication bus
One part that covers all applications
Reduces board space, system cost and
complexity, and time to market
Features
RoHS lead free and lead-solder-exempt products are
available
Wide input voltage range: 3V–13.2V
High continuous output current: 15A
Wide programmable output voltage range: 0.5V–5.5V
Active digital current share
Single-wire serial communication bus for frequency
synchronization, programming, and monitoring
Optimal voltage positioning with programmable slope
of the VI line
Overcurrent, overvoltage, undervoltage, and
overtemperature protections with programmable
thresholds and types
Programmable fixed switching frequency 0.5-1.0MHz
Programmable turn-on and turn-off delays
Programmable turn-on and turn-off voltage slew rates
with tracking protection
Programmable feedback loop compensation
Power Good signal with programmable limits
Programmable fault management
Start up into the load pre-biased up to 100%
Full rated current sink
Real time voltage, current, and temperature
measurements, monitoring, and reporting
Small footprint SMT package: 8x32mm
Low profile of 14mm
Compatible with conventional pick-and-place
equipment
Wide operating temperature range
UL 60950-1/CSA 22.2 No. 60950-1-07 Second
Edition, IEC 60950-1: 2005, and EN 60950-1:2006
Description
Power-One‟s point-of-load converters are recommended for use with regulated bus converters in an Intermediate
Bus Architecture (IBA). The ZY7115 is an intelligent, fully programmable step-down point-of-load DC-DC module
integrating digital power conversion and intelligent power management. When used with ZM7300 Series Digital
Power Managers, the ZY7115 completely eliminates the need for external components for sequencing, tracking,
protection, monitoring, and reporting. All parameters of the ZY7115 are programmable via the industry-standard
I2C communication bus and can be changed by a user at any time during product development and service.
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 2 of 33
Reference Documents:
ZM7300 Digital Power Manager Data Sheet
ZM7300 Digital Power Manager Programming Manual
Power-One I2C Graphical User Interface
ZM00056-KIT USB to I2C Adapter Kit User Manual
1. Ordering Information
ZY
71
15
x
y
–
zz
Product
family:
Z-One
Module
Series:
Intelligent
POL
Converter
Output
Current:
15A
Output voltage setpoint
accuracy:
L – 1.2% or 20mV,
whichever is greater.
H1 – 1.0% or 10mV,
whichever is greater
RoHS compliance:
No suffix - RoHS
compliant with Pb
solder exemption2
G - RoHS compliant
for all six substances
Dash
Packaging Option3:
T1 – 500pcs T&R
T2 – 100pcs T&R
T3 – 50pcs T&R
Q1 – 1pc sample for
evaluation only
______________________________________
1 Contact factory for availability.
2 The solder exemption refers to all the restricted materials except lead in solder. These materials are Cadmium (Cd), Hexavalent chromium
(Cr6+), Mercury (Hg), Polybrominated biphenyls (PBB), Polybrominated diphenylethers (PBDE), and Lead (Pb) used anywhere except in
solder.
3 Packaging option is used only for ordering and not included in the part number printed on the POL converter label.
4 The evaluation board is available in only one configuration: ZM7300-KIT-HKS.
Example: ZY7115HG-T2: A 100-piece reel of RoHS compliant POL converters with the output voltage setpoint of
1.0% or 10mV, whichever is greater. Each POL converter is labeled ZY7115HG.
2. Absolute Maximum Ratings
Stresses in excess of the absolute maximum ratings may cause performance degradation, adversely affect long-
term reliability, and cause permanent damage to the converter.
Parameter
Min
Max
Units
Operating Temperature
-40
105
C
Input Voltage
15
VDC
Output Current
-15
15
ADC
3. Environmental and Mechanical Specifications
Parameter
Min
Nom
Max
Units
Ambient Temperature Range
-40
85
C
Storage Temperature (Ts)
-55
125
C
Weight
15
grams
MTBF
4.82
MHrs
Peak Reflow Temperature
245
220
260
C
C
Lead Plating
100% Matte Tin
Moisture Sensitivity Level
3
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 3 of 33
4. Electrical Specifications
Specifications apply at the input voltage from 3V to 13.2V, output load from 0 to 15A, ambient temperature from -40°C to 85°C,
100F output capacitance, and default performance parameters settings unless otherwise noted.
4.1 Input Specifications
Parameter
Conditions/Description
Min
Nom
Max
Units
Input voltage (VIN)
At VIN<4.75V, VLDO pin needs to be
connected to an external voltage source
higher than 4.75V
3
13.2
VDC
Input Current (at no load)
VIN4.75V, VLDO pin connected to VIN
50
mADC
Undervoltage Lockout (VLDO
connected to VIN)
Ramping Up
Ramping Down
4.2
3.75
VDC
VDC
Undervoltage Lockout (VLDO
connected to VAUX=5V)
Ramping Up
Ramping Down
3.0
2.5
VDC
VDC
External Low Voltage Supply
Connect to VLDO pin when VIN<4.75V
4.75
13.2
VDC
VLDO Input Current
Current drawn from the external low
voltage supply at VLDO=5V
50
mADC
4.2 Output Specifications
Parameter
Conditions/Description
Min
Nom
Max
Units
Output Voltage Range (VOUT)
Programmable1
Default (no programming)
0.5
0.5
5.5
VDC
VDC
Output Voltage Setpoint Accuracy
VIN=12V, IOUT=0.5*IOUT MAX,
FSW=500kHz, room temperature
(See Ordering Information)
Output Current (IOUT)
VIN MIN to VIN MAX
-152
15
ADC
Line Regulation
VIN MIN to VIN MAX
±0.3
%VOUT
Load Regulation
0 to IOUT MAX
±0.2
%VOUT
Dynamic Regulation
Peak Deviation
Settling Time
Slew rate 2.5A/s, 50 - 100% load step
COUT=300F, FSW=1MHz
to 10% of peak deviation
100
50
mV
s
Output Voltage Peak-to-Peak
Ripple and Noise
BW=20MHz
Full Load
VIN=5.0V, VOUT=0.5V, FSW=500kHz
VIN=13.2V, VOUT=0.5V, FSW=500kHz
VIN=5.0V, VOUT=2.5V, FSW=500kHz
VIN=13.2V, VOUT=2.5V, FSW=500kHz
VIN=13.2V, VOUT=5.0V, FSW=500kHz
10
15
10
25
35
mV
mV
mV
mV
mV
mV
Temperature Coefficient
VIN=12V, IOUT=0.5*IOUT MAX
20
ppm/°C
Switching Frequency
Default
Programmable, 250kHz steps
500
500
1,000
kHz
kHz
Duty Cycle Limit
Default
Programmable, 1.56% steps
0
90.5
95
%
%
1 ZY7115 is a step-down converter, thus the output voltage is always lower than the input voltage as show in Figure 1.
2 At the negative output current (bus terminator mode) efficiency of the ZY7115 degrades resulting in increased internal power dissipation.
Therefore maximum allowable negative current under specific conditions is 20% lower than the current determined from the derating curves
shown in paragraph 5.5.
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 4 of 33
5.0
4.0
3.0
2.0
1.0
VOUT
[V]
14.012.010.08.06.02.0 4.0
Min Load 0.2A
VIN [V]
3.0 3.15 13.25.5
2.5
5.5
4.5
3.5
1.5
0.5
6.25
Figure 1. Output Voltage as a Function of Input Voltage and Output Current
4.3 Protection Specifications
Parameter
Conditions/Description
Min
Nom
Max
Units
Output Overcurrent Protection
Type
Default
Programmable
Non-Latching, 130ms period
Latching/Non-Latching
Threshold
Default
Programmable in 11 steps
60
170
170
%IOUT
%IOUT
Threshold Accuracy
-25
25
%IOCP.SET
Output Overvoltage Protection
Type
Default
Programmable
Non-Latching, 130ms period
Latching/Non-Latching
Threshold
Default
Programmable in 10% steps
1101
130
130
%VO.SET
%VO.SET
Threshold Accuracy
Measured at VO.SET=2.5V
-2
2
%VOVP.SET
Delay
From instant when threshold is exceeded until
the turn-off command is generated
6
μs
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 5 of 33
Output Undervoltage Protection
Type
Default
Programmable
Non-Latching, 130ms period
Latching/Non-Latching
Threshold
Default
Programmable in 5% steps
75
75
85
%VO.SET
%VO.SET
Threshold Accuracy
Measured at VO.SET=2.5V
-2
2
%VUVP.SET
Delay
From instant when threshold is exceeded until
the turn-off command is generated
6
μs
Overtemperature Protection
Type
Default
Programmable
Non-Latching, 130ms period
Latching/Non-Latching
Turn Off Threshold
Temperature is increasing
130
C
Turn On Threshold
Temperature is decreasing after the module was
shut down by OTP
120
C
Threshold Accuracy
-5
5
C
Delay
From instant when threshold is exceeded until
the turn-off command is generated
6
μs
Tracking Protection (when Enabled)
Type
Default
Programmable
Disabled
Latching/Non-Latching, 130ms period
Threshold
Enabled during output voltage ramping up
250
mVDC
Threshold Accuracy
-50
50
mVDC
Delay
From instant when threshold is exceeded until
the turn-off command is generated
6
μs
Overtemperature Warning
Threshold
Always enabled, reported in Status register
120
C
Threshold Accuracy
-5
5
C
Hysteresis
3
C
Delay
From instant when threshold is exceeded until
the warning signal is generated
6
μs
Power Good Signal (PGOOD pin)
Logic
VOUT is inside the PG window
VOUT is outside the PG window
High
Low
N/A
Lower Threshold
Default
Programmable in 5% steps
90
90
95
%VO.SET
%VO.SET
Upper Threshold
110
%VO.SET
Delay
From instant when threshold is exceeded until
status of PG signal changes
6
μs
Threshold Accuracy
Measured at VO.SET=2.5V
-2
2
%VO.SET
___________________
1 Minimum OVP threshold is 1.0V
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 6 of 33
4.4 Feature Specifications
Parameter
Conditions/Description
Min
Nom
Max
Units
Current Share
Type
Active, Single Line
Maximum Number of Modules
Connected in Parallel
IOUT MIN≥20%*IOUT NOM
10
Maximum Number of Modules
Connected in Parallel
IOUT MIN=0
4
Current Share Accuracy
IOUT MIN≥20%*IOUT NOM
±20
%IOUT
Interleave
Interleave (Phase Shift)
Default
Programmable in 11.25 steps
0
0
348.75
Degree
degree
Sequencing
Turn ON Delay
Default
Programmable in 1ms steps
0
0
255
ms
ms
Turn OFF Delay
Default
Programmable in 1ms steps
0
0
63
ms
ms
Tracking
Turn ON Slew Rate
Default
Programmable in 7 steps
0.1
0.1
8.331
V/ms
V/ms
Turn OFF Slew Rate
Default
Programmable in 7 steps
-0.1
-0.1
-8.331
V/ms
V/ms
Optimal Voltage Positioning
Load Regulation
Default
Programmable in 7 steps
0
0
6.27
mV/A
mV/A
Feedback Loop Compensation
Zero1 (Effects phase lead and
increases gain in mid-band)
Programmable
0.05
50
kHz
Zero 2 (Effects phase lead and
increases gain in mid-band)
Programmable
0.05
50
kHz
Pole 1 (Integrator Pole, effects
loop gain)
Programmable
0.05
50
kHz
Pole 2 (Effects phase lag and
limits gain in mid-band)
Programmable
1
1000
kHz
Pole 3 (High frequency low- pass
filter to limit PWM noise)
Programmable
1
1000
kHz
Monitoring
Voltage Monitoring Accuracy
1 LSB=22mV
-2%VOUT
– 1 LSB
2%VOUT
+ 1 LSB
mV
Current Monitoring Accuracy
20%*IOUT NOM < IOUT < IOUT NOM
-20
+20
%IOUT
Temperature Monitoring Accuracy
Junction temperature of POL controller
-5
+5
C
Remote Voltage Sense (+VS and –VS pins)
Voltage Drop Compensation
Between +VS and VOUT
300
mV
Voltage Drop Compensation
Between -VS and PGND
100
mV
___________________
1 Achieving fast slew rates under specific line and load conditions may require feedback loop adjustment
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 7 of 33
4.5 Signal Specifications
Parameter
Conditions/Description
Min
Nom
Max
Units
VDD
Internal supply voltage
3.15
3.3
3.45
V
SYNC/DATA Line (SD pin)
ViL_sd
LOW level input voltage
-0.5
0.3 x VDD
V
ViH_sd
HIGH level input voltage
0.75 x
VDD
VDD + 0.5
V
Vhyst_sd
Hysteresis of input Schmitt trigger
0.25 x
VDD
0.45 x
VDD
V
VoL
LOW level sink current @ 0.5V
14
60
mA
Tr_sd
Maximum allowed rise time 10/90%VDD
300
ns
Cnode_sd
Added node capacitance
5
10
pF
Ipu_sd
Pull-up current source at Vsd=0V
0.3
1.0
mA
Freq_sd
Clock frequency of external SD line
475
525
kHz
Tsynq
Sync pulse duration
22
28
% of clock
cycle
T0
Data=0 pulse duration
72
78
% of clock
cycle
Inputs: ADDR0…ADDR4, EN, IM
ViL_x
LOW level input voltage
-0.5
0.3 x VDD
V
ViH_x
HIGH level input voltage
0.7 x VDD
VDD+0.5
V
Vhyst_x
Hysteresis of input Schmitt trigger
0.1 x VDD
0.3 x VDD
V
RdnL_ADDR
External pull down resistance
ADDRX forced low
10
kOhm
Power Good and OK Inputs/Outputs
Iup_PG
Pull-up current source input forced low PG
25
110
μA
Iup_OK
Pull-up current source input forced low OK
175
725
μA
ViL_x
LOW level input voltage
-0.5
0.3 x VDD
V
ViH_x
HIGH level input voltage
0.7 x VDD
VDD+0.5
V
Vhyst_x
Hysteresis of input Schmitt trigger
0.1 x VDD
0.3 x VDD
V
IoL
LOW level sink current at 0.5V
4
20
mA
Current Share Bus (CS pin)
Iup_CS
Pull-up current source at VCS = 0V
0.84
3.1
mA
ViL_CS
LOW level input voltage
-0.5
0.3 x VDD
V
ViH_CS
HIGH level input voltage
0.75 x
VDD
VDD+0.5
V
Vhyst_CS
Hysteresis of input Schmitt trigger
0.25 x
VDD
0.45 x
VDD
V
IoL
LOW level sink current at 0.5V
14
60
mA
Tr_CS
Maximum allowed rise time 10/90% VDD
100
ns
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 8 of 33
5. Typical Performance Characteristics
5.1 Efficiency Curves
70
75
80
85
90
95
0 1.5 3 4.5 6 7.5 9 10.5 12 13.5 15
Output Current, A
Efficiency, %
Vout=0.5V Vout=1.2V Vout=2.5V
Figure 2. Efficiency vs. Load. Vin=3.3V, Fsw=500kHz
70
75
80
85
90
95
100
0 1.5 3 4.5 6 7.5 9 10.5 12 13.5 15
Output Current, A
Efficiency, %
Vout=0.5V Vout=1.2V
Vout=2.5V Vout=3.3V
Figure 3. Efficiency vs. Load. Vin=5V, Fsw=500kHz
50
55
60
65
70
75
80
85
90
95
0 1.5 3 4.5 6 7.5 9 10.5 12 13.5 15
Output Current, A
Efficiency, %
Vout=0.5V Vout=1.2V Vout=2.5V
Vout=3.3V Vout=5.0V
Figure 4. Efficiency vs. Load. Vin=12V, Fsw=500kHz
65
70
75
80
85
90
95
0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5
Output Voltage, V
Efficiency, %
Vin=3.3V Vin=5V Vin=12V
Figure 5. Efficiency vs. Output Voltage, Iout=15A,
Fsw=500kHz
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 9 of 33
65
70
75
80
85
90
95
3 4 5 6 7 8 9 10 11 12
Input Voltage, V
Efficiency, %
Vout=0.5V Vout=1.2V
Vout=2.5V Vout=3.3V
Figure 6. Efficiency vs. Input Voltage. Iout=15A, Fsw=500kHz
88
89
90
91
92
93
94
95
0 1.5 3 4.5 6 7.5 9 10.5 12 13.5 15
Output Current, A
Efficiency
500kHz 750kHz 1MHz
Figure 7. Efficiency vs. Load. Vin=3.3V, Vout=2.5V
76
78
80
82
84
86
88
90
0 1.5 3 4.5 6 7.5 9 10.5 12 13.5 15
Output Current, A
Efficiency
500kHz 750kHz 1MHz
Figure 8. Efficiency vs. Load. Vin=5V, Vout=1.2V
83
85
87
89
91
93
95
0 1.5 3 4.5 6 7.5 9 10.5 12 13.5 15
Output Current, A
Efficiency
500kHz 750kHz 1MHz
Figure 9. Efficiency vs. Load. Vin=12V, Vout=5V
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 10 of 33
80
82
84
86
88
90
92
94
500 750 1000
Switching Frequency, kHz
Efficiency
3.3Vin/2.5Vout 5Vin/1.2Vout 12Vin/5Vout
Figure 10. Efficiency vs. Switching Frequency. Iout=15A
5.2 Turn-On Characteristics
Figure 11. Tracking Turn-On. Rising Slew Rate is
Programmed at 0.5V/ms.
Vin=12V, Ch1 – V1, Ch2 – V2, Ch3 – V3
Figure 12. Turn-On with Different Rising Slew Rates.
Rising Slew Rates are Programmed as follows: V1-
1V/ms, V2-0.5V/ms, V3-0.2V/ms.
Vin=12V, Ch1 – V1, Ch2 – V2, Ch3 – V3
Figure 13. Sequenced Turn-On. Rising Slew Rate is
Programmed at 1V/ms. V2 Delay is 2ms, V3 delay
is 4ms. Vin=12V, Ch1 – V1, Ch2 – V2, Ch3 – V3
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 11 of 33
Figure 14. Turn On with Sequencing and Tracking. Rising
Slew Rate Programmed at 0.2V/ms, V1 and V3
delays are programmed at 20ms.
Vin=12V, Ch1 – V1, Ch2 – V2, Ch3 – V3
Figure 15. Turn On into Prebiased Load. V3 is Prebiased by
V2 via a Diode.
Vin=12V, Ch1 – V1, Ch2 – V2, Ch3 – V3
5.3 Turn-Off Characteristics
Figure 16. Tracking Turn-Off. Falling Slew Rate is
Programmed at 0.5V/ms.
Vin=12V, Ch1 – V1, Ch2 – V2, Ch3 – V3
Figure 17. Turn-Off with Tracking and Sequencing. Falling
Slew Rate is Programmed at 0.5V/ms.
Vin=12V, Ch1 – V1, Ch2 – V2, Ch3 – V3
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 12 of 33
5.4 Transient Response
The pictures below show the deviation of the output
voltage in response to the 50-100-50% step load at
2.5A/μs. In all tests the POL converters were
operating at 1MHz and had 6x47μF ceramic
capacitors connected across the output pins.
Bandwidth of the feedback loop was programmed for
faster transient response.
Figure 18. Vin=12V, Vout=1V. Bandwidth is 40kHz
Figure 19. Vin=12V, Vout=5V. Bandwidth is 40kHz
Figure 20. Vin=5V, Vout=1V. Bandwidth is 40kHz
Figure 21. Vin=5V, Vout=2.5V. Bandwidth is 40kHz
Figure 22. Vin=3V, Vout=1V. Bandwidth is 30kHz
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 13 of 33
5.5 Thermal Derating Curves
5
6
7
8
9
10
11
12
13
14
15
45 50 55 60 65 70 75 80 85
Temperature, 'C
Output Current, A
NC 100 LFM 200 LFM 400 LFM 600 LFM
Figure 23. Thermal Derating Curves. Vin=13.2V, Vout=2.5V, Fsw=500kHz
5
6
7
8
9
10
11
12
13
14
15
45 50 55 60 65 70 75 80 85
Temperature, 'C
Output Current, A
0 LFM 100 LFM 200 LFM 400 LFM 600 LFM
Figure 24. Thermal Derating Curves. Vin=13.2V, Vout=5V, Fsw=500kHz
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 14 of 33
5
6
7
8
9
10
11
12
13
14
15
45 50 55 60 65 70 75 80 85
Temperature, 'C
Output Current, A
0 LFM 100 LFM 200 LFM 400 LFM 600 LFM
Figure 25. Thermal Derating Curves. Vin=13.2V, Vout=5V, Fsw=1,000kHz
6. Typical Application
ZY7115
V1
V2
V3
CS
SD
OK_A
OK_B
ADDR
ADDR
ADDR
ADDR
DPM
I2C
Intermediate Voltage Bus
ZY7115
ZY7115
ZY7115
OK_C
Figure 26. Block Diagram of Typical Multiple Output Application with Digital Power Manager and I2C Interface
The block diagram of a typical application of ZY7115 point-of-load converters (POL) is shown in Figure 26. The
system includes multiple POLs and a ZM7300 series Digital Power Manager (DPM). All POLs are connected to the
DPM and to each other via a single-wire SD (sync/data) line. The line provides synchronization of all POLs to the
master clock generated by the DPM and simultaneously performs bidirectional data transfer between POLs and
the DPM. Each POL has a unique 5-bit address programmed by grounding respective address pins. To enable the
current share, CS pins of POLs connected in parallel are linked together.
There are three groups of POLs in the application, groups A, B, and group C. A group is defined as a number of
POLs interconnected via OK pins. Grouping of POLs enables users to program, control, and monitor multiple
POLs simultaneously and execute advanced fault management schemes.
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 15 of 33
The complete schematic of the application is shown in Figure 27.
Figure 27. Complete Schematic of the Application Shown in Figure 26. Intermediate Bus Voltage is from 4.75V to 13.2V.
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 16 of 33
7. Pin Assignments and Description
Pin
Name
Pin
Number
Pin
Type
Buffer
Type
Pin Description
Notes
VLDO
1
P
Low Voltage Dropout
Connect to an external voltage source higher than
4.75V, if VIN<4.75V. Connect to VIN, if VIN≥4.75V
IM
2
Not Used
Leave floating
NC
3
Not Used
Leave floating
NC
4
Not Used
Leave floating
NC
5
Not Used
Leave floating
NC
6
Not Used
Leave floating
NC
7
Not Used
Leave floating
NC
8
Not Used
Leave floating
VREF
9
Not Used
Leave floating
EN
10
Connect to PGND
Connect to PGND
OK
11
I/O
PU
Fault/Status Condition
Connect to OK pin of other Z-POL and/or DPM.
Leave floating, if not used
SD
12
I/O
PU
Sync/Data Line
Connect to SD pin of DPM
PGOOD
13
I/O
PU
Power Good
TRIM
14
Not Used
Leave floating
CS
15
I/O
PU
Current Share
Connect to CS pin of other Z-POLs connected in
parallel
ADDR4
16
I
PU
POL Address Bit 4
Tie to PGND for 0 or leave floating for 1
ADDR3
17
I
PU
POL Address Bit 3
Tie to PGND for 0 or leave floating for 1
ADDR2
18
I
PU
POL Address Bit 2
Tie to PGND for 0 or leave floating for 1
ADDR1
19
I
PU
POL Address Bit 1
Tie to PGND for 0 or leave floating for 1
ADDR0
20
I
PU
POL Address Bit 0
Tie to PGND for 0 or leave floating for 1
-VS
21
I
PU
Negative Voltage Sense
Connect to the negative point close to the load
+VS
22
I
PU
Positive Voltage Sense
Connect to the positive point close to the load
VOUT
23
P
Output Voltage
PGND
24
P
Power Ground
VIN
25
P
Input Voltage
Legend: I=input, O=output, I/O=input/output, P=power, A=analog, PU=internal pull-up
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 17 of 33
8. Programmable Features
Performance parameters of ZY7115 POL converters
can be programmed via the industry standard I2C
communication bus without replacing any
components or rewiring PCB traces. Each parameter
has a default value stored in the volatile memory
registers detailed in Table 1. The setup registers 00h
through 14h are programmed at the system power-
up. When the user programs new performance
parameters, the values in the registers are
overwritten. Upon removal of the input voltage, the
default values are restored.
Table 1. ZY7115 Memory Registers
Register
Content
Address
PC1
Protection Configuration 1
00h
PC2
Protection Configuration 2
01h
PC3
Protection Configuration 3
02h
DON
Turn-On Delay
05h
DOF
Turn-Off Delay
06h
TC
Tracking Configuration
03h
INT
Interleave Configuration and
Frequency Selection
04h
RUN
RUN Register
15h
ST
Status Register
16h
VOS
Output Voltage Setpoint
07h
CLS
Current Limit Setpoint
08h
DCL
Duty Cycle Limit
09h
B1
Dig Controller Denominator z-1
Coefficient
0Ah
B2
Dig Controller Denominator z-2
Coefficient
0Bh
B3
Dig Controller Denominator z-3
Coefficient
0Ch
C0L
Dig Controller Numerator z0
Coefficient, Low Byte
0Dh
C0H
Dig Controller Numerator z0
Coefficient, High Byte
0Eh
C1L
Dig Controller Numerator z-1
Coefficient, Low Byte
0Fh
C1H
Dig Controller Numerator z-1
Coefficient, High Byte
10h
C2L
Dig Controller Numerator z-2
Coefficient, Low Byte
11h
C2H
Dig Controller Numerator z-2
Coefficient, High Byte
12h
C3L
Dig Controller Numerator z-3
Coefficient, High Byte
13h
C3H
Dig Controller Numerator z-3
Coefficient, Low Byte
14h
VOM
Output Voltage Monitoring
17h
IOM
Output Current Monitoring
18h
TMP
Temperature Monitoring
19h
ZY7115 converters can be programmed using the
Graphical User Interface or directly via the I2C bus by
using high and low level commands as described in
the "ZM7300 Digital Power Manager Programming
Manual”.
ZY7115 parameters can be reprogrammed at any
time during the system operation and service except
for the digital filter coefficients, the switching
frequency and the duty cycle limit, that can only be
changed when the POL is turned off.
8.1 Output Voltage
The output voltage can be programmed in the POL
Configure Output window shown in the Figure 28 or
directly via the I2C bus by writing into the VOS
register shown in Figure 29.
Figure 28. POL Configure Output Window
VOS7
VOS6
VOS5
VOS4
VOS2
VOS1
VOS0
Bit 7
Bit 0
R = Readable bit
W = Writable bit
U = Unimplemented bit,
read as „0‟
- n = Value at POR reset
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
Bit 7:0 VOS[7:0], Output voltage setting
00h: corresponds to 0.5000V
01h: corresponds to 0.5125V
…
77h: corresponds to 1.9875V
78h: corresponds to 2.0000V
79h: corresponds to 2.025V
…
F9h: corresponds to 5.225V
FAh: corresponds to 5.250V
FBh: corresponds to 5.300V
…
FFh: corresponds to 5.500V
VOS3
Figure 29. Output Voltage Setpoint Register VOS
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 18 of 33
8.1.1 Output Voltage Setpoint
The output voltage programming range is from 0.5V
to 5.5V. Within this range, there are 256 predefined
voltage setpoints. To improve resolution of the output
voltage settings, the voltage range is divided into
three sub-ranges as shown in Table 2.
Table 2. Output Voltage Adjustment Resolution
VOUT MIN, V
VOUT MAX, V
Resolution, mV
0.500
2.000
12.5
2.025
5.25
25
5.3
5.5
50
8.1.2 Output Voltage Margining
If the output voltage needs to be varied by a certain
percentage, the margining function can be utilized.
The margining can be programmed in the POL
Configure Output window or directly via the I2C bus
using high level commands as described in the
„”DPM Programming Manual”.
In order to properly margin POLs that are connected
in parallel, the POLs must be members of one of the
Parallel Buses. Refer to the DPM Configure Devices
window shown in Figure 56.
8.1.3 Optimal Voltage Positioning
Optimal voltage positioning increases the voltage
regulation window by properly positioning the output
voltage setpoint. Positioning is determined by the
load regulation that can be programmed in the POL
Configure Output window shown in Figure 28 or
directly via the I2C bus by writing into the CLS
register shown in Figure 39.
Figure 30 illustrates optimal voltage positioning
concept. If no load regulation is programmed, the
headroom (voltage differential between the output
voltage setpoint and a regulation limit) is
approximately half of the voltage regulation window.
When load regulation is programmed, the output
voltage will decrease as the output current
increases, so the VI characteristic will have a
negative slope. Therefore, by properly selecting the
operating point, it is possible to increase the
headroom as shown in the picture.
Upper Regulation
Limit
Lower Regulation
Limit
Light
Load
VOUT
IOUT
VI Curve Without
Load Regulation
VI Curve With
Load Regulation
Heavy
Load
Headroom without
Load Regulation
Operating
Point
Headroom with
Load Regulation
Figure 30. Concept of Optimal Voltage Positioning
Increased headroom allows tolerating larger voltage
deviations. For example, the step load change from
light to heavy load will cause the output voltage to
drop. If the optimal voltage positioning is utilized, the
output voltage will stay within the regulation window.
Otherwise, the output voltage will drop below the
lower regulation limit. To compensate for the voltage
drop external output capacitance will need to be
added, thus increasing cost and complexity of the
system.
The effect of optimal voltage positioning is shown in
Figure 31 and Figure 32. In this case, switching
output load causes large peak-to-peak deviation of
the output voltage. By programming load regulation,
the peak to peak deviation is dramatically reduced.
Figure 31. Transient Response without Optimal Voltage
Positioning
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 19 of 33
Figure 32. Transient Response with Optimal Voltage
Positioning
8.2 Sequencing and Tracking
Turn-on delay, turn-off delay, and rising and falling
output voltage slew rates can be programmed in the
POL Configure Sequencing window shown in Figure
33 or directly via the I2C bus by writing into the DON,
DOF, and TC registers, respectively. The registers
are shown in Figure 34, Figure 35, and Figure 37.
Figure 33. POL Configure Sequencing Window
8.2.1 Turn-On Delay
Turn-on delay is defined as an interval from the
application of the Turn-On command until the output
voltage starts ramping up.
DON7
DON6
DON5
DON4
DON2
DON1
DON0
Bit 7
Bit 0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
Bit 7:0 DON[7:0]: Turn-on delay time
00h: corresponds to 0ms delay after turn-on command has occurred
…
FFh: corresponds to 255ms delay after turn-on command has occurred
DON3
Figure 34. Turn-On Delay Register DON
8.2.2 Turn-Off Delay
---
---
DOF5
DOF4
DOF2
DOF1
DOF0
Bit 7
Bit 0
U
U
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
Bit 7:6 Unimplemented, read as „0‟
Bit 5:0 DOF[5:0]: Turn-off delay time
00h: corresponds to 0ms delay after turn-off command has occurred
…
3Fh: corresponds to 63ms delay after turn-off command has occurred
DOF3
Figure 35. Turn-Off Delay Register DOF
Turn-off delay is defined as an interval from the
application of the Turn-Off command until the output
voltage reaches zero (if the falling slew rate is
programmed) or until both high side and low side
switches are turned off (if the slew rate is not
programmed). Therefore, for the slew rate controlled
turn-off the ramp-down time is included in the turn-off
delay as shown in Figure 36.
Turn-Off
Command
Internal
ramp-down
command
VOUT
User programmed turn-off delay, TDF
Calculated
delay TD
Time
Ramp-down time, TF
Ramp-down time, TF
Falling slew
rate dVF/dT
Figure 36. Relationship between Turn-Off Delay and Falling
Slew Rate
As it can be seen from the figure, the internally
calculated delay TD is determined by the equation
below.
dT
dV
V
TT F
OUT
DFD
,
For proper operation TD shall be greater than zero.
The appropriate value of the turn-off delay needs to
be programmed to satisfy the condition.
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 20 of 33
If the falling slew rate control is not utilized, the turn-
off delay only determines an interval from the
application of the Turn-Off command until both high
side and low side switches are turned off. In this
case, the output voltage ramp-down process is
determined by load parameters.
8.2.3 Rising and Falling Slew Rates
The output voltage tracking is accomplished by
programming the rising and falling slew rates of the
output voltage. To achieve programmed slew rates,
the output voltage is being changed in 12.5mV steps
where duration of each step determines the slew
rate. For example, ramping up a 1.0V output with a
slew rate of 0.5V/ms will require 80 steps duration of
25μs each.
Duration of each voltage step is calculated by
dividing the master clock frequency generated by the
DPM. Since all POLs in the system are synchronized
to the master clock, the matching of voltage slew
rates of different outputs is very accurate as it can be
seen in Figure 11 and Figure 16.
During the turn on process, a POL not only delivers
current required by the load (ILOAD), but also charges
the load capacitance. The charging current can be
determined from the equation below:
dt
dV
CI R
LOADCHG
Where, CLOAD is load capacitance, dVR/dt is rising
voltage slew rate, and ICHG is charging current.
When selecting the rising slew rate, a user needs to
ensure that
OCPCHGLOAD III
Where IOCP is the overcurrent protection threshold of
the ZY7115. If the condition is not met, then the
overcurrent protection will be triggered during the
turn-on process. To avoid this, dVR/dt and the
overcurrent protection threshold should be
programmed to meet the condition above.
Figure 37. Tracking Configuration Register TC
8.3 Protections
ZY7115 Series converters have a comprehensive set
of programmable protections. The set includes the
output over- and undervoltage protections,
overcurrent protection, overtemperature protection,
tracking protection, overtemperature warning, and
Power Good signal. Status of protections is stored in
the ST register shown in Figure 38.
Figure 38. Protection Status Register ST
Thresholds of overcurrent, over- and undervoltage
protections, and Power Good limits can be
programmed in the POL Configure Output window or
directly via the I2C bus by writing into the CLS and
PC2 registers shown in Figure 39 and Figure 40.
---
R2
R1
R0
F2
F1
F0
Bit 7
Bit 0
R
=
Readable bit
W
=
Writable bit
U
=
Unimplemented bit,
read as „0‟
-
n
=
Value at POR reset
U
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-0
R/W-1
Bit 7
Unimplemented
, read as „0‟
Bit 6:4
R[2:0]
: Value of Vo rising slope
0: corresponds to 0.1V/ms (default)
1: corresponds to 0.2V/ms
2: corresponds to 0.5V/ms
3: corresponds to 1.0V/ms
4: corresponds to 2.0V/ms
5: corresponds to 5.0V/ms
6: corresponds to 8.3V/ms
7: corresponds to 8.3V/ms
Bit 3
SC
, Slew rate control at turn-off
0: Slew rate control is disabled
1: Slew rate control is enabled
Bit 2:0
F[2:0]
: Value of Vo falling slope
0: corresponds to -0.1V/ms (default)
1: corresponds to -0.2V/ms
2: corresponds to -0.5V/ms
3: corresp
onds to -1.0V/ms
4: corresponds to -2.0V/ms
5: corresponds to -5.0V/ms
6: corresponds to –8.3V/ms
7: corresponds to –8.3V/ms
SC
TP
PG
TR
OT
UV
OV
PV
Bit 7
Bit 0
R
=
Readable bit
W
=
Writable bit
U
=
Unimplemented bit,
read as „0‟
-
n
=
Value at POR reset
R-1
R-0
R-1
R-1
R-1
R-1
R-1
R-1
Bit 7
TP
: Temperature Warning
Bit 6
PG
: Power Good Warning
Bit 5
TR
: Tracking Fault
Bit 4
OT
: Overtemperature Fault
Bit 3
OC
: Overcurrent Fault
Bit 2
UV
: Undervoltage Fault
Bit 1
OV
: Overvoltage Error
Bit 0
PV
: Phase Voltage Error
Note:
- An activated warning/fault/error is encoded as „0‟
OC
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 21 of 33
LR2
LR1
LR0
TCE
CLS2
CLS1
CLS0
Bit 7
Bit 0
R = Readable bit
W = Writable bit
U = Unimplemented bit,
read as „0‟
- n = Value at POR reset
R/W-0
R/W-0
R/W-0
R/W-1
R/W-0
R/W-1
R/W-1
R/W-1
Bit 7:5 LR[2:0], Load regulation configuration
000: 0 V/A/Ohm
001: 0.39 V/A/Ohm
010: 0.78 V/A/Ohm
011: 1.18 V/A/Ohm
100: 1.57 V/A/Ohm
101: 1.96 V/A/Ohm
110: 2.35 V/A/Ohm
111: 2.75 V/A/Ohm
Bit 4 TCE, Temperature compensation enable
0: disabled
1: enabled
Bit 3:0 CLS[3:0], Current limit setting
0h: corresponds to 37%
1h: corresponds to 47%
…
Bh: corresponds to 140%
Values higher than Bh are translated to Bh (140%)
CLS3
Figure 39. Current Limit Setpoint Register CLS
---
---
---
PGLL
OVPL0
UVPL1
UVPL0
Bit 7
Bit 0
R = Readable bit
W = Writable bit
U = Unimplemented bit,
read as „0‟
- n = Value at POR reset
U
U
U
R/W-0
R/W-0
R/W-0
R/W-0
R/W-1
Bit 7:5 Unimplemented, read as „0‟
Bit 4 PGLL: Set Power Good Low Level
1 = 95% of Vo
0 = 90% of Vo (Default)
Bit 3:2 OVPL[1:0]: Set Over Voltage Protection
Level
00 = 110% of Vo
01 = 120% of Vo
10 = 130% of Vo (Default)
11 = 130% of Vo
Bit 1:0 UVPL[1:0]: Set Under Voltage Protection Level
00 = 75% of Vo (Default)
01 = 80% of Vo
10 = 85% of Vo
11 = 90% of Vo
OVPL1
Figure 40. Protection Configuration Register PC2
Note that the overvoltage and undervoltage
protection thresholds and Power Good limits are
defined as percentages of the output voltage.
Therefore, the absolute levels of the thresholds
change when the output voltage setpoint is changed
either by output voltage adjustment or by margining.
In addition, a user can change type of protections
(latching or non-latching) or disable certain
protections. These settings are programmed in the
DPM Configure Fault window shown in Figure 41 or
directly via the I2C by writing into the PC1 register
shown in Figure 42.
Figure 41. POL Configure Fault Window
Figure 42. Protection Configuration Register PC1
If the non-latching protection is selected, a POL will
attempt to restart every 130ms until the condition
that triggered the protection is removed. When
restarting, the output voltages follow tracking and
sequencing settings.
If the latching type is selected, a POL will turn off and
stay off. The POL can be turned on after 130ms, if
the condition that caused the fault is removed and
the respective bit in the ST register was cleared, or
TRE
PVE
TRP
OTP
UVP
OVP
PVP
Bit 7
Bit 0
R
=
Readable bit
W
=
Writable bit
U
=
Unimplemented bit,
read as „0‟
-
n
=
Value at POR reset
R/W-0
R/W-1
R/W-0
R/W-0
R/W-0
R/W-1
R/W-1
R/W-0
Bit 7
TRE
: Tracking fault enable
1 = enabled
0 = disabled
Bit 6
PVE
: Phase voltage error enable
1 = enabled
0 = disabled
Bit 5
TRP
: Tracking fault protection
1 = latching
0 = non latching
Bit 4
OTP
: Overtemperature protection configuration
1 = latching
0 = non latching
Bit 3
OCP
: Overcurrent protection configuration
1 = latching
0 = non latching
Bit 2
UVP
: Undervoltage protection configuration
1 = latching
0 = non latching
Bit 1
OVP
: Overvoltage protection configuration
1 = latching
0 = non latching
Bit 0
PVP
: Phase Voltage Protection
1 = latching
0 = non latching
OCP
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 22 of 33
the Turn On command was recycled, or the input
voltage was recycled.
All protections can be classified into three groups
based on their effect on system operation: warnings,
faults, and errors.
8.3.1 Warnings
This group includes Overtemperature Warning and
Power Good Signal. The warnings do not turn off
POLs but rather generate signals that can be
transmitted to a host controller via the I2C bus.
8.3.1.1 Overtemperature Warning
The Overtemperature Warning is generated when
temperature of the controller exceeds 120°C. The
Overtemperature Warning changes the PT bit of the
status register ST to 0 and sends the signal to the
DPM. Reporting is enabled in the DPM Configure
Faults window or directly via the I2C by writing into
the PC3 register shown in Figure 44. When the
temperature falls below 117°C, the PT bit is cleared
and the Overtemperature Warning is removed.
8.3.1.2 Power Good
Power Good is an open collector output that is pulled
low, if the output voltage is outside of the Power
Good window. The window is formed by the Power
Good High threshold that is equal to 110% of the
output voltage and the Power Good Low threshold
that can be programmed at 90 or 95% of the output
voltage.
The Power Good protection is only enabled after the
output voltage reaches its steady state level. The PG
pin is pulled low during transitions of the output
voltage from one level to other as shown in Figure
43.
The Power Good Warning pulls the Power Good pin
low and changes the PG bit of the status register ST
to 0. It sends the signal to the DPM, if the reporting is
enabled. When the output voltage returns within the
Power Good window, the PG pin is pulled high, the
PG bit is cleared and the Power Good Warning is
removed. The Power Good pin can also be pulled
low by an external circuit to initiate the Power Good
Warning.
Note: To retrieve status information, Status Monitoring in the DPM
Configure Devices window should be enabled (refer to
Digital Power Manager Data Sheet). The DPM will retrieve
the status information from each POL on a continuous
basis.
8.3.2 Faults
This group includes overcurrent, overtemperature,
undervoltage, and tracking protections. Triggering
any protection in this group will turn off the POL.
8.3.2.1 Overcurrent Protection
Overcurrent protection is active whenever the output
voltage of the POL exceeds the pre-bias voltage (if
any). When the output current reaches the OC
threshold, the output voltage will start decreasing. As
soon as the output voltage decreases below the
undervoltage protection threshold, the OC fault
signal is generated, the POL turns off and the OC bit
in the register ST is changed to 0. Both high side and
low side switches of the POL are turned off instantly
(fast turn-off).
The temperature compensation is added to keep the
OC threshold approximately constant at
temperatures above room temperature. Note that the
temperature compensation can be disabled in the
POL Configure Output window or directly via the I2C
by writing into the CLS register. However, it is
recommended to keep the temperature
compensation enabled.
8.3.2.2 Undervoltage Protection
The undervoltage protection is only active during
steady state operation of the POL to prevent
nuisance tripping. If the output voltage decreases
below the UV threshold and there is no OC fault, the
UV fault signal is generated, the POL turns off, and
the UV bit in the register ST is changed to 0. The
output voltage is ramped down according to
sequencing and tracking settings (regular turn-off).
8.3.2.3 Overtemperature Protection
Overtemperature protection is active whenever the
POL is powered up. If temperature of the controller
exceeds 130°C, the OT fault is generated, POL turns
off, and the OT bit in the register ST is changed to 0.
The output voltage is ramped down according to
sequencing and tracking settings (regular turn-off).
If non-latching OTP is programmed, the POL will
restart as soon as the temperature of the controller
decreases below the Overtemperature Warning
threshold of 120°C.
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 23 of 33
8.3.2.4 Tracking Protection
Tracking protection is active only when the output
voltage is ramping up. The purpose of the protection
is to ensure that the voltage differential between
multiple rails being tracked does not exceed 250mV.
This protection eliminates the need for external
clamping diodes between different voltage rails
which are frequently recommended by ASIC
manufacturers.
When the tracking protection is enabled, the POL
continuously compares actual value of the output
voltage to its programmed value as defined by the
output voltage and its rising slew rate. If absolute
value of the difference exceeds 250mV, the tracking
fault signal is generated, the POL turns off, and the
TR bit in the register ST is changed to 0. Both high
side and low side switches of the POL are turned off
instantly (fast turn-off).
The tracking protection can be disabled, if it
contradicts requirements of a particular system (for
example turning into high capacitive load where
rising slew rate is not important). It can be disabled
in the DPM Configure Faults window or directly via
the I2C bus by writing into the PC1 register.
Figure 43. Protections Enable Conditions
8.3.3 Errors
The group includes overvoltage protection and the
phase voltage error. The phase voltage error is not
available in ZY7115.
8.3.3.1 Overvoltage Protection
The overvoltage protection is active whenever the
output voltage of the POL exceeds the pre-bias
voltage (if any). If the output voltage exceeds the
overvoltage protection threshold, the overvoltage
error signal is generated, the POL turns off, and the
OV bit in the register ST is changed to 0. The high
side switch is turned off instantly, and simultaneously
the low side switch is turned on to ensure reliable
protection of sensitive loads. The low side switch
provides low impedance path to quickly dissipate
energy stored in the output filter and achieve
effective voltage limitation.
The OV threshold can be programmed from 110% to
130% of the output voltage setpoint, but not lower
than 1.0V.
8.3.4 Faults and Errors Propagation
The feature adds flexibility to the fault management
scheme by giving users control over propagation of
fault signals within and outside of the system. The
propagation means that a fault in one POL can be
programmed to turn off other POLs and devices in
the system, even if they are not directly affected by
the fault.
8.3.4.1 Grouping of POLs
ZY-Series POLs can be arranged in several groups
to simplify fault management. A group of POLs is
defined as a number of POLs with interconnected
OK pins. A group can include from 1 to 32 POLs. If
OVP Threshold
Output Voltage
Time
Vo
1.0V
Enable command
0
1
OCP enabled
0
1
prebiased output
OTP
continuously enabled
OVP Threshold
OVP Threshold
UVP Threshold
UVP Threshold
UVP Threshold
PG Low Threshold
PG Low Threshold
PG Low Threshold
PG High=110%VOUT
PG High=110%VOUT
PG High=110%VOUT
Output Voltage
Output Voltage
Power Good
Signal
1
0
Tracking
Thresholds
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 24 of 33
fault propagation within a group is desired, the
propagation bit needs to be checked in the DPM
Configure Faults Window. The parameters can also
be programmed directly via the I2C bus by writing
into the PC3 register shown in Figure 44.
When propagation is enabled, the faulty POL pulls its
OK pin low. A low OK line initiates turn-off of other
POLs in the group.
Figure 44. Protection Configuration Register PC3
In addition, the OK lines can be connected to the
DPM to facilitate propagation of faults and errors
between groups. One DPM can control up to 4
independent groups. To enable fault propagation
between groups, the respective bit needs to be
checked in the DPM Configure Faults window, Group
Fault Propagation sub window shown in Figure 45.
Figure 45. DPM Configure Faults Window
In this case low OK line will signal DPM to pull other
OK lines low to initiate shutdown of other POLs as
programmed in the DPM Configure Faults window. If
an error is propagated, the DPM can also generate
commands to turn off a front end (a DC-DC
converter generating the intermediate bus voltage)
and trigger an optional crowbar protection to
accelerate removal of the IBV voltage.
8.3.4.2 Propagation Process
Propagation of a fault (OCP, UVP, OTP, and TRP)
initiates regular turn-off of other POLs. The faulty
POL in this case performs either the regular or the
fast turn-off depending on a specific fault as
described in section 8.3.2.
Propagation of an error initiates fast turn-off of other
POLs. The faulty POL performs the fast turn-off and
turns on its low side switch.
Example of the fault propagation is shown in Figure
46 - Figure 47. In this three-output system (refer to
the block diagram in Figure 26), the POL powering
the output V3 (Ch 1 in the picture) encounters the
undervoltage fault after the turn-on. When the fault
propagation is not enabled, the POL turns off and
generates the UV fault signal. Because the UV fault
triggers the regular turn off, the POL meets its turn-
off delay and falling slew rate settings during the
turn-ff process as shown in Figure 46. Since the UV
fault is programmed to be non-latching, the POL will
attempt to restart every 130ms, repeating the
process described above until the condition causing
the undervoltage is removed.
PTM
PGM
TRP
OTP
UVP
OVP
PVP
Bit 7
Bit 0
R
=
Readable bit
W
=
Writable bit
U
=
Unimplemented bit,
read as „0‟
-
n
=
Value at POR reset
R/W-0
R/W-0
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
Bit 7
PTM
: Temperature warning Message
1 = enabled
0 = disabled
Bit 6
PGM
: Power good message
1 = enabled
0 = disabled
Bit 5
TRP
: Tracking fault propagation
1 = enabled
0 = disabled
Bit 4
OTP
: Overtemperature fault propagation
1 = enabled
0 = disabled
Bit 3
OCP
: Overcurrent fault propagation
1 = enabled
0 = disabled
Bit 2
UVP
: Undervoltage fault propagation
1 = enabled
0 = disabled
Bit 1
OVP
: Overvoltage error propagation
1 = enabled
0 = disabled
Bit 0
PVP
: Phase voltage error propagation
1 = enabled
0 = disabled
OCP
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 25 of 33
If the fault propagation between groups is enabled,
the POL powering the output V3 pulls its OK line low
and the DPM propagates the signal to the POL
powering the output V1 that belongs to other group.
The POL powering the output V1 (Ch3 in the picture)
executes the regular turn-off. Since both V1 and V3
have the same delay and slew rate settings they will
continue to turn off and on synchronously every
130ms as shown in Figure 47 until the condition
causing the undervoltage is removed. The POL
powering the output V2 continues to ramp up until it
reaches its steady state level.
130ms is the interval from the instant of time when
the output voltage ramps down to zero until the
output voltage starts to ramp up again. Therefore,
the 130ms hiccup interval is guaranteed regardless
of the turn-off delay setting.
Figure 46. Turn-On into UVP on V3. The UV Fault Is
Programmed To Be Non-Latching. Ch1 – V3 (Group
C), Ch2 – V2, Ch3 – V1 (Group A)
Figure 47. Turn-On into UVP on V3. The UV Fault Is
Programmed To Be Non-Latching and Propagate
From Group C to Group A. Ch1 – V3 (Group C),
Ch2 – V2, Ch3 – V1 (Group A)
Summary of protections, their parameters and
features are shown in Table 3
Table 3. Summary of Protections Parameters and Features
Code
Name
Type
When Active
Turn
Off
Low Side
Switch
Propagation
Disable
PT
Temperature
Warning
Warning
Whenever VIN is applied
No
N/A
Readable by
DPM
No
PG
Power Good
Warning
During steady state
No
N/A
Readable by
DPM
No
TR
Tracking
Fault
During ramp up
Fast
Off
Regular turn off
Yes
OT
Overtemperature
Fault
Whenever VIN is applied
Regular
Off
Regular turn off
No
OC
Overcurrent
Fault
When VOUT exceeds prebias
Fast
Off
Regular turn off
No
UV
Undervoltage
Fault
During steady state
Regular
Off
Regular turn off
No
OV
Overvoltage
Error
When VOUT exceeds prebias
Fast
On
Fast turn off
No
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 26 of 33
8.4 PWM Parameters
Z-Series POLs utilize the digital PWM controller. The
controller enables users to program most of the
PWM performance parameters, such as switching
frequency, interleave, duty cycle, and feedback loop
compensation.
8.4.1 Switching Frequency
The switching frequency can be programmed in the
POL Controller Compensation window shown in
Figure 48 or directly via the I2C bus by writing into
the INT register shown in Figure 49. Note that the
content of the register can be changed only when the
POL is turned off.
Switching actions of all POLs connected to the SD
line are synchronized to the master clock generated
by the DPM. Each POL is equipped with a PLL and a
frequency divider so they can operate at multiples
(including fractional) of the master clock frequency
as programmed by a user. The POL converters can
operate at 500 kHz, 750 kHz, and 1 MHz. Although
synchronized, switching frequencies of different
POLs are independent of each other. It is
permissible to mix POLs operating at different
frequencies in one system. It allows optimizing
efficiency and transient response of each POL in the
system individually.
Figure 48. POL Configure Controller Compensation Window
Figure 49. Interleave Configuration Register INT
8.4.2 Interleave
Interleave is defined as a phase delay between the
synchronizing slope of the master clock on the SD
pin and PWM signal of a POL. The interleave can be
programmed in the POL Configure Controller
Compensation window or directly via the I2C bus by
writing into the INT register.
Every POL generates switching noise. If no
interleave is programmed, all POLs in the system
switch simultaneously and noise reflected to the
input source from all POLs is added together as
shown in Figure 50.
Figure 50. Input Voltage Noise, No Interleave
FRQ2
FRQ1
FRQ0
INT4
INT2
INT1
INT0
Bit 7
Bit 0
R
=
Readable bit
W
=
Writable bit
U
=
Unimplemented bit,
read as „0‟
-
n
=
Value at POR reset
R/W-0
R/W-0
R/W-0
R/W-0
1)
R/W-0
1)
R/W-0
1)
R/W-0
1)
R/W-0
1)
Bit 7:5
FRQ[2:0]
: PWM Frequency Selection
000: 500kHz
001: 750kHz
010: 1000lHz
011: 1250kHz
100: 1250kHz
101: 1500kHz
110: 1750kHz
111: 2000kHz
Bit 4:0
INT[4:0]
: Interleave position
00h: Ton starts with 0.0° Phase lag to SD Line
01h: Ton starts wi
th 11.25° Phase lag to SD Line
02h: Ton starts with 22.50° Phase lag to SD Line
…
1Fh: Ton starts with 348.75° Phase lag to SD Line
1)
Initial value depends on the state of the Interleave Mode (
IM
) Input:
IM=Open:
At POR reset the
5 corresponding ADDRESS bits are loaded
IM=Low:
At POR reset a 0 is loaded
INT3
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 27 of 33
Figure 51 shows the input voltage noise of the three-
output system with programmed interleave. Instead
of all three POLs switching at the same time as in
the previous example, the POLs V1, V2, and V3
switch at 67.5°, 180°, and 303.75°, respectively.
Noise is spread evenly across the switching cycle
resulting in more than 1.5 times reduction. To
achieve similar noise reduction without the interleave
will require the addition of an external LC filter.
Figure 51. Input Voltage Noise with Interleave
Similar noise reduction can be achieved on the
output of POLs connected in parallel. Figure 52 and
Figure 53 show the output noise of two ZY7115s
connected in parallel without and with 180°
interleave, respectively. Resulting noise reduction is
more than 2 times and is equivalent to doubling
switching frequency or adding extra capacitance on
the output of the POLs.
Figure 52. Output Voltage Noise, Full Load, No Interleave
Figure 53. Output Voltage Noise, Full Load, 180 Interleave
The ZY7115 interleave feature is similar to that of
multiphase converters, however, unlike in the case of
multiphase converters, interleave does not have to
be equal to 360/N, where N is the number of POLs in
a system. ZY7115 interleave is independent of the
number of POLs in a system and is fully
programmable in 11.25 steps. It allows maximum
output noise reduction by intelligently spreading
switching energy.
Note: Due to noise sensitivity issues that may occur in limited
cases, it is recommended to avoid phase lag settings of
112.5 and 123.75 degrees, otherwise false PG and/or OV
indications may occur.
8.4.3 Duty Cycle Limit
The ZY7115 is a step-down converter therefore VOUT
is always less than VIN. The relationship between the
two parameters is characterized by the duty cycle
and can be estimated from the following equation:
MININ
OUT
V
V
DC .
,
Where, DC is the duty cycle, VOUT is the required
maximum output voltage (including margining),
VIN.MIN is the minimum input voltage.
It is good practice to limit the maximum duty cycle of
the controller's PWM to a somewhat higher value
compared to the steady-state duty cycle as
expressed by the above equation. This will further
protect the output from excessive voltages. The duty
cycle limit can be programmed in the POL Configure
Controller Compensation window or directly via the
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 28 of 33
I2C bus by writing into the DCL register shown in
Figure 54.
DCL5
DCL4
DCL3
DCL2
DCL0
HI
LO
Bit 7
Bit 0
R = Readable bit
W = Writable bit
U = Unimplemented bit,
read as „0‟
- n = Value at POR reset
R/W-1
R/W-1
R/W-1
R/W-0
R/W-0
R/W-0
R/W-0
R/W-1
Bit 7:2 DCL[5:0], Duty Cycle Limitation
00h: 0
01h: 1/64
…
3Fh: 63/64
Bit 1: HI, ADC high saturation feed-forward
0: disabled
1: enabled
Bit 0: LO, ADC low saturation feed-forward
0: disabled
1: enabled
DCL1
Figure 54. Duty Cycle Limit Register
8.4.4 ADC Saturation Feedforward
To speed up the PWM response in case of heavy
dynamic loads, the duty cycle can be forced either to
0 or the duty cycle limit depending on the polarity of
the transient. This function is equivalent to having
two comparators defining a window around the
output voltage setpoint. When an error signal is
inside the window, it will produce gradual duty cycle
change proportional to the error signal. If the error
signal goes outside the window (usually due to large
output current steps), the duty cycle will change to its
limit in one switching cycle. In most cases this will
significantly improve transient response of the
controller, reducing amount of required external
capacitance.
Under certain circumstances, usually when the
maximum duty cycle limit significantly exceeds its
nominal value, the ADC saturation can lead to the
overcompensation of the output error. The
phenomenon manifests itself as low frequency
oscillations on the output of the POL. It can usually
be reduced or eliminated by disabling the ADC
saturation or limiting the maximum duty cycle to 120-
140% of the calculated value. It is not recommended
to use ADC saturation for output voltages higher
than 2.0V.
The ADC saturation feedforward can be
programmed in the POL Configure Controller
Compensation window or directly via the I2C bus by
writing into the DCL register.
8.4.5 Feedback Loop Compensation
Feedback loop compensation can be programmed in
the GUI POL Configure Controller Compensation
window by setting frequency of poles and zeros of
the transfer function.
The transfer function of the POL converter is shown
in Figure 55. It is a third order function with two zeros
and three poles. Pole 1 is the integrator pole, Pole 2
is used in conjunction with Zero 1 and Zero 2 to
adjust the phase lead and limit the gain increase in
mid band. Pole 3 is used as a high frequency low-
pass filter to limit PWM noise.
Z1 P1 Z2 P2 P3
0.1 1 10 100 1000
Freq
[kHz]
Magnitude[dB]
10
20
30
40
50
0.1 1 10 100 1000
Freq
[kHz]
-90
-45
-135
-180
0
+45
Phase
[°]
P1: Pole 1
P2: Pole 3
P3: Pole 3
Z1: Zero 1
Z2: Zero 2
Figure 55. Transfer Function of PWM
Positions of poles and zeroes are determined by
coefficients of the digital filter. The filter is
characterized by four numerator coefficients (C0, C1,
C2, C3) and three denominator coefficients (B1, B2,
B3). The coefficients are automatically calculated
when desired frequency of poles and zeros is
entered in the GUI POL Configure Controller
Compensation window. The coefficients are stored in
the C0H, C0L, C1H, C1L, C2H, C2L, C3H, C3L, B1,
B2, and B3 registers.
Note: The GUI automatically transforms zero and pole
frequencies into the digital filter coefficients. It is strongly
recommended to use the GUI to determine the filter
coefficients.
Programming feedback loop compensation allows
optimizing POL performance for various application
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 29 of 33
conditions. For example, increase in bandwidth can
significantly improve dynamic response.
8.5 Current Share
The POL converters are equipped with the digital
current share function. To activate the current share,
interconnect the CS pins of the POLs connected in
parallel. The digital signal transmitted over the CS
line sets output currents of all POLs to the same
level.
When POLs are connected in parallel, they must be
included in the same parallel bus in the DPM
Configure Devices window shown in Figure 56. In
this case, the GUI automatically copies critical
parameters of one POL onto all POLs connected to
the parallel bus. It makes it impossible to configure
different performance parameters for POLs
connected in parallel except for interleave and load
regulation settings that are independent. The
interleave allows to reduce and move the output
noise of the converters connected in parallel to
higher frequencies as shown in Figure 52 and Figure
53. The load regulation allows controlling the current
share loop gain in case of small signal oscillations. It
is recommended to always add a small amount of
load regulation to one of the converters connected in
parallel to reduce loop gain and therefore improve
stability.
8.6 Performance Parameters Monitoring
The POL converters can monitor their own
performance parameters such as output voltage,
output current, and temperature.
The output voltage is measured at the output sense
pins, output current is measured using the ESR of
the output inductor and temperature is measured by
the thermal sensor built into the controller IC. Output
current readings are adjusted based on temperature
readings to compensate for the change of ESR of
the inductor with temperature.
An 8-Bit Analog to Digital Converter (ADC) converts
the output voltage, output current, and temperature
into a digital signal to be transmitted via the serial
interface. The ADC allows a minimum sampling
frequency of 1 kHz for all three values.
Monitored parameters are stored in registers (VOM,
IOM, and TMON) that are continuously updated. If
the Retrieve Monitoring bits in the DPM Configure
Devices window shown in Figure 56 are checked,
those registers are being copied into the ring buffer
located in the DPM. Contents of the ring buffer can
be displayed in the DPM Monitor Window shown in
Figure 57 or it can be read directly via the I2C bus
using high and low level commands as described in
the "ZM7300 Digital Power Manager Programming
Manual”.
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 30 of 33
Figure 56. DPM Configure Devices Window
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 31 of 33
Figure 57. DPM Monitor Window
9. Safety
The ZY7115 POL converters do not provide
isolation from input to output. The input devices
powering ZY7115 must provide relevant isolation
requirements according to all IEC60950 based
standards. Nevertheless, if the system using the
converter needs to receive safety agency approval,
certain rules must be followed in the design of the
system. In particular, all of the creepage and
clearance requirements of the end-use safety
requirements must be observed. These requirements
are included in UL60950 - CSA60950-00 and
EN60950, although specific applications may have
other or additional requirements.
The ZY7115 POL converters have no internal fuse. If
required, the external fuse needs to be provided to
protect the converter from catastrophic failure. Refer
to the “Input Fuse Selection for DC/DC converters”
application note on www.power-one.com for proper
selection of the input fuse. Both input traces and the
chassis ground trace (if applicable) must be capable
of conducting a current of 1.5 times the value of the
fuse without opening. The fuse must not be placed in
the grounded input line.
Abnormal and component failure tests were
conducted with the POL input protected by a fast-
acting 65 V, 15 A, fuse. If a fuse rated greater than
15 A is used, additional testing may be required.
In order for the output of the ZY7115 POL converter
to be considered as SELV (Safety Extra Low
Voltage), according to all IEC60950 based
standards, the input to the POL needs to be supplied
by an isolated secondary source providing a SELV
also.
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 32 of 33
10. Mechanical Drawings
All Dimensions are in mm
Tolerances:
0.5-10 0.1
10-100 0.2
Pin Coplanarity: 0.1 max
1.5
10
3.4
0.25
10.25129.75
9.112
15.75
8.25±0.3
3.25
Pin 1
3.5
SMT Pickup
Center Point
1.5±0.1
0.4
(x20)
27.94
32±0.3
13.4
14±0.3
2.03
1.27
(x10)
0.6 2.54 1.27
(x10) 4.3
2.5
0.6
SMT Pickup Tab
Tilt Specification:
<5° from vertical,
after assembly
Figure 58. Mechanical Drawing
Figure 59. Pinout Diagram (Bottom View)
ZY7115 15A DC-DC Intelligent POL Data Sheet
3V to 13.2V Input 0.5V to 5.5V Output
MDS-0006 Rev. 3.8, 5-May-2011 www.power-one.com Page 33 of 33
6 9
8.6
32
10 10 6
0.8
2
(x 22) Pin 1
1.27
(x 10) 1.27
(x 10)
2.54 2.03
1.8
1.2
4
(x 3)
Unexposed thermal copper
area associated with each pad
must be free from other traces
Figure 60. Recommended Pad Sizes
10
10
6.4
8.68.6 8.6
0.45mm Ø Thermal Via x 16 0.45mm Ø Thermal Via x 16 0.45mm Ø Thermal Via x 16
4.0
Recommended via diameter is 0.45mm Barrel wall plating of > 25um Pitch <1.00mm
Figure 61. Recommended PCB Layout for Multilayer PCBs
Notes:
1. NUCLEAR AND MEDICAL APPLICATIONS - Power-One products are not designed, intended for use in, or authorized for use as critical
components in life support systems, equipment used in hazardous environments, or nuclear control systems without the express written
consent of the respective divisional president of Power-One, Inc.
2. TECHNICAL REVISIONS - The appearance of products, including safety agency certifications pictured on labels, may change depending on
the date manufactured. Specifications are subject to change without notice.
I2C is a trademark of Philips Corporation.