AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
1
Features
• Low start-up power supply voltage :1.7V(CH6)
• Wide supply voltage range from 2.4V to 6.5V
(CH6); 3.6V to 6.5V(CH1~5)
• Up to 1MHz operating frequency
• Supports for down and up/down Zeta
synchronous rectification conversion(CH1)
• Supports for up and up/down SEPIC
synchronous rectification conversion(CH2, CH5)
• Supports for up, flyback and up/down SEPIC
conversion
AT1393/C: CH2,CH3, CH4 , CH5 and CH6
AT1393A/B:CH2,CH3,CH5 and CH6
• Supports for inverting conversion
AT1393A:CH4
• Synchronized rectification on CH1,CH2,CH5
• Power ON/OFF control function
• Built-in Soft-Start function
• Built-in Short-Circuit Protection circuit.
• LQFP 48 package
General Description
The AT1393 provides a complete power solution
for digital still and video cameras through the
integration of synchronous rectification topology ,
soft start function and short circuit detection
function. This IC is ideal for applications that use
either 2 or 3 alkaline or NIMH batteries as well as
those using a single Li-ion battery.
Applications
• Digital Cameras
• CCD Imaging Devices
• Camcorders
Pin Assignment
Ordering Information
Part Number Package Marking
AT1393F LQFP48 AT1393F
AT1393F_PBF LQFP48, PB-Free AT1393F,date code with one bottom line
AT1393F_GRE LQFP48,Green AT1393F,date code with two bottom line
AT1393AF LQFP48 AT1393AF
AT1393AF_PBF LQFP48, PB-Free AT1393AF,date code with one bottom line
AT1393AF_GRE LQFP48,Green AT1393AF,date code with two bottom line
Aimtron reserves the right without notice to change this circuitry and specifications.
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
2
Pin Description
Pin No. Pin name Function
1SWOUTOut
p
ut Switch Control Circuit Out
p
u
t
2 SWIN Output Switch Control Circuit Input
3 FB6 CH6 Error Amplifier Output
4 IN6 CH6 Error Amplifier Inverted Input
5 CIN6 CH6 Soft Start Setting
6 DTC5 CH5 Dead Time Control
7 FB5 CH5 Error Amplifier Output
8 IN5 CH5 Error Amplifier Inverted Input
9 INA4 CH4 Inverting Amplifier Input
10 OUTA4 CH4 Inverting Amplifier Output
11 FB4 CH4 Error Amplifier Output
12 IN4 CH4 Error Amplifier Inverted Input
13 INS4 CH4 Short Detection Comparator Inverter Input
14 DTC4 CH4 Dead Time Control
15 CS CH1 to CH5 Soft Start Setting
16 VREF Reference 2.5V Output
17 AGND Ground
18 CSCP Timer Latch Shout-Circuit Detection Input
19 VCC Power Supply
20 CTL CH6 Power Supply Control Input
21 CTL1_ 2 CH1 and CH2 ON/OFF Control Input
22 CTL3 CH3 ON/OFF Control Input
23 CTL4 CH4 ON/OFF Control Input
24 CTL5 CH5 ON/OFF Control Input
25 RT Oscillation Frequency Setting Resistor
26 CT Oscillation Frequency Setting Capacitor
27 VB Triangular Wave Oscillator Regulator Output
28 IN3 CH3 Error Amplifier Inverted Input
29 FB3 CH3 Error Amplifier Output
30 DTC3 CH3 Dead Time Control
31 IN2 CH2 Error Amplifier Inverted Input
32 FB2 CH2 Error Amplifier Output
33 DTC2 CH2 Dead Time Control
34 IN1 CH1 Error Amplifier Inverted Input
35 FB1 CH1 Error Amplifier Output
36 DTC1 CH1 Dead Time Control
37 OUT1-1 CH1 Main Side Output(P-CH MOSFET)
38 OUT1-2 CH1 Synchronous Rectifier Side Output
39 OUT2-1 CH2 Main Side Output
40 OUT2-2 CH2 Synchronous Rectifier Side Output
41 OUT3 CH3 Output(N-CH MOSFET)
42 PVCC Output Circuit Power Supply
43 OUT4 CH4 Output
AT1393/C:Drive N-CH MOSFET for boost converter
AT1393A/B:Drive P-CH MOSFET for inverting
44 PGND Output Circuit Ground
45 OUT5-1 CH5 Main Side Output(N_CH MOSFET)
46 OUT5-2 CH5 Synchronous Rectifier Side Output
47 OUT6 CH6 Output
48 RB Output Current Setting Resistor
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
3
Absolute Maximum Ratings
Ratin
g
Parameter Symbol Condition Min Max Unit
Power supply voltage Vcc -- -- 7 V
Output current Io Output pin -- 20 mA
Output peak current Io Output pin, Duty≦5% -- 200 mA
Power dissipation PDTa≦25℃ (LQFP-48P) -- 860 mW
Operating temperature TOPT -- -30 85 ℃
Storage temperature TSTG -- -55 125 ℃
ESD Susceptibility (HBM) -- -- 2KV
ESD Susceptibility (MM) -- -- 200 V
Recommended Operating Conditions
Value
Parameter Symbol Condition Min T
yp
Max Unit
Startup power supply voltage Vcc CH6 1.7 -- 5.5 V
CH6 2.4 5.0 5.5 V
Power supply voltage Vcc CH1 to CH5 3.6 5.0 5.5 V
Reference voltage output current IOR VREF pin -1 -- 0 mA
VB pin output current IBVB pin -0.5 -- 0 mA
IN1 to IN5, INA4, INS4
pins 0--VccV
Input voltage VIN
IN6 pin 0 -- Vcc-0.9 V
Control input voltage VCTL CTL pin 0 -- 7 V
OUT pin (CH1 to CH5) -- 2 15 mA
OUT pin (CH6) 1 2 15 mAOutput current Io
OUT pin -- 1 4 mA
Output current setting resister RBRB6 pin 2.4 24 51 kΩ
Oscillator fOSC -- 100 500 1000 kHz
Timing capacitor CT-- 47 100 560 pF
Timing resistor RT-- 8.2 18 100 kΩ
Cs CH1 to CH5 -- 0.027 1.0 μF
Soft start capacitor C+IN6 CH6 -- 0.47 1.0 μF
Short detection capacitor CSCP -- -- 0.1 1.0 μF
VB pin capacitor CVB -- 0.082 0.1 -- μF
Operating ambient temperature Ta -- -20 25 85 ℃
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
4
Electrical characteristics
(Ta=25℃, VCC=PVCC=5V)
Value
Parameter Symbol Condition Min T
yp
Max Unit
Reference voltage VREF -- 2.40 2.50 2.60 V
Output voltage
temperature
stability
△VREF
/VREF
Ta = -30℃ to 85℃-- 0.5 -- %
Input stability Line VCC=3.6 to 5.5V -10 -- 10 mV
Reference voltage block
[REF]
Load stability Load VREF=0mA to –1mA -10 -- 10 mV
Threshold voltage VTH VIN=0V to VCC 2.6 2.8 3.0 V
Hysteresis width VH-- -- 0.2 -- V
CH1 to CH5
Reset voltage VRST VIN=VCC to 0V 1.20 1.30 1.40 V
Under voltage
lockout block
[U.V.L.O]
CH6
Threshold voltage VTH VIN=0V to VCC 1.35 1.5 1.65 V
Soft start
block
[CS]
Charge current ICS -- -1.4 -1.0 -0.6 μA
Soft start
block
[CIN6]
Charge current ICIN6 -3.0 -2.5 -2.0 μA
Threshold voltage VTH -- 0.65 0.70 0.75 V
Input standby
voltage VSTB -- -- 50 100 mV
Input latch voltage VI-- -- 50 100 mV
Short circuit
detection block
[SCP]
Input source
current ICSCP -- -1.4 -1.0 -0.6 μA
Oscillator
frequency fOSC CT=100pF, RT=18kΩ450 500 550 kHz
Frequency
stability for
voltage
△f
/fdv VCC=4V to 5.5V -- 1 10 %
Triangular wave
oscillator block
[OSC]
Frequency
stability for
temperature
△f
/fdt Ta=-30℃ to 85℃-- 1 20 %
Threshold voltage VTH FB=IN 1.24 1.25 1.26 V
VT temperature
stability △VT/VTTa = -30℃ to 85℃-- 0.5 -- %
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
5
IN=0V
(CH1 to CH3, CH5) -320 -80 -- nA
Input bias current IB
IN=0V (CH4) -120 -30 -- nA
Voltage gain AVDC 60 100 -- dB
Frequency
bandwidth BW AV=0dB -- 1.0 -- MHz
VOH -- 2.2 2.4 -- V
Output voltage VOL -- -- 50 200 mV
Output source
current ISOURCE FB=2.3V -- -2.0 -1.0 mA
Error Amplifier block
(CH1 to CH5)
[Error Amp]
Output sink
current ISINK FB=1.45V 70 140 -- μA
Threshold voltage VTH FB=0.55 1.24 1.25 1.26 V
Temperature
stability △VT/VTTa = -30℃ to 85℃-- 0.5 -- %
Input bias current IBIN=0V -100 -20 -- nA
Voltage gain AVDC 60 75 -- dB
Frequency
bandwidth BW AV=0dB -- 1.0 -- MHz
VOH -- 1.1 1.3 -- V
Output voltage VOL -- -- 0 200 mV
Output source
current ISOURCE FB=0.55V -- -2.0 -1.0 mA
Error amplifier block
(CH6)
[Error Amp]
Output sink
current ISINK FB=0.55V 60 120 -- μA
Input offset
voltage VIO OUT=1.25V -10 0 10 mV
Input bias current IBIN=0V -120 -30 -- nA
Voltage gain AVDC 60 100 -- dB
Frequency
bandwidth BW AV=0dB -- 1.0 -- MHz
VOH -- 2.2 2.4 -- V
Output voltage VOL -- -- 50 200 mV
Output source
current ISOURCE OUT=1.25V -- -2.0 -1.0 mA
Inverting amplifier block
(CH4)
[Inv Amp]
Output sink
current ISINK OUT=1.25V 70 140 -- μA
Threshold voltage VTH CH1 to CH5 0.97 1.00 1.03 %
IN=0V
(CH1 to CH3, CH5) -320 -80 -- nA
Short detect
comparator
(CH1 to CH5)
[SCP Comp]
Input bias current IB
IN=0V (CH4) -200 -50 nA
Short detect
comparator
(CH6)
Threshold voltage VTH -- 0.8 0.9 1.0 V
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
6
VT0 Duty = 0 % 1.0 1.1 -- V
Threshold voltage
VTmax Duty = 100 % -- 1.8 1.9 V
PWM Comp.
(CH1 to CH5)
[PWM Comp]
Input current IDTC
DTC=0.4V
(CH1 to CH5) -1.0 -0.3 -- μA
VT0 Duty = 0 % 0.2 0.3 -- V
Threshold voltage
VTmax Duty = 100 % -- 0.74 0.84 V
PWM Comp.
(CH6)
[PWM Comp]
Maximum duty
cycle Dtr CT=100pF, RT=18kΩ
RB=24kΩ70 80 -- %
Output source
current ISOURCE OUT=VCC/2 -- -130 -- mA
Output sink
current ISINK OUT=VCC/2 -- 100 -- mA
ROH OUT = -15mA -- 18 30 Ω
Output block
(CH1,2,4,5)
[Pch MOS]
Output ON
resistor ROL OUT = 15mA -- 16 25 Ω
Output source
current ISOURCE OUT=VCC/2 -- -130 -- mA
Output sink
current ISINK OUT=VCC/2 -- 100 -- mA
ROH OUT = -15mA -- 18 30 Ω
Output block
(CH1 to CH5)
[Nch MOS]
Output ON
resistor ROL OUT = 15mA -- 16 25 Ω
Output source
current ISOURCE OUT=0.7V,RB=24kΩ-2.6 -2.0 -1.4 mA
Output
block
(CH6)
[Drive]
Output sink
current ISINK Duty≦5%,OUT=0.7V -- 40 -- mA
VIH SWOUT = ”L” level 1.5 -- 6.5 V
SW input voltage
VIL SWOUT = ”H” level 0 -- 0.4 V
Input current ISWIN SWIN = 5V -- 100 200 μA
Output source
current ISOURCE
Duty≧95%,
SWOUT=0V -- -9 -- mA
Output sink
current ISINK Duty≦5%, SWOUT=5V -- 17 -- mA
ROH SWOUT = -4mA -- 250 400 Ω
Output switch control block
[SW]
Output ON
resistor ROL SWOUT = 4mA -- 100 150 Ω
VIH Active mode 1.5 -- 6.5 V
CTL input voltage
VIL Standby mode 0 -- 0.4 V
Control block
(CTL, CTL1
to CTL5)
[CTL]
Input current ICTL CTL = 5V -- 100 200 μA
VCC Standby
current Icss CTL=0V -- -- 10 μA
PVCC Standby
current Icss(o) CTL=0V -- -- 10 μA
General
VCC Nominal
Supply current Icc CTL, CTL1 to CTL5 =
5V -- 6 9 mA
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
7
Block Diagram
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
8
Application Circuit
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
9
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
10
Typical Characteristics
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
11
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
12
Function Description
1. Power Converter
＊ Reference voltage block
A temperature independent voltage of typical value at 2.50V is generated from the
power source by the reference voltage circuit, which is used as a reference voltage
for all internal circuitry and supplies load current to external device up to 1 mA.
＊ Triangular oscillator block
A triangular oscillation waveform is generated by connecting a timing resistor (RT)
to pin 25 and a timing capacitor (CT) to pin 26. The resulting waveforms CT
(amplitude at 0.3V to 0.8V), CT1 (in phase with CT with amplitude at 1.1V to
1.8V) and CT2 (reverse phase with CT with amplitude at 1.1V to 1.8V) serve as
input to the PWM comparator.
＊ Error amplifier block
The error amplifier controls the error signal to the PWM comparator by sensing
the DC/DC converter output voltage. Furthermore, by connecting feedback
resistor and capacitor from the output pin to the inverted input pin of the error
amplifier, an arbitrary loop gain can be set to make the system stable.
＊ Inverting amplifier block
The inverting amplifier detects the negative DC/DC converter output voltage
and sends a control signal to the error amplifier.
＊ PWM comparator block
The PWM comparator converts the input voltage to pulse width and thereby the
duty cycle of the DC/DC converter.
Channels 1, 2, and 5 main sides, channel 3, 4, and 6 : The comparator keeps the
output transistor turn on while the error
amplifier output voltage and DTC voltage
are higher than the triangular wave voltage.
Channels 1, 2, and 5 synchronous rectification sides : The comparator keeps the
output transistor turn on while the error
amplifier output voltage are lower than the
triangular wave voltage.
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
13
＊ Output block
A totem pole configuration is designed for the output block and can drive external
MOSFET or transistor.
2. Channel Control
The channels are turned on and turned off according to the voltage levels at the
CTL, CTL12, CTL3, CTL4, and CTL5 as described in the following table.
Voltage level at control (CTL) pin Channel on/off status
CTL CTL1,2 CTL3 CTL4 CTL5 CH6 CH1,2 CH3 CH4 CH5
L X X X X OFF (standby state)
LOFF
LHOFF ON
LOFF
L
HH
OFF
ON ON
LOFF
LHOFF ON
LOFF
L
H
HH
OFF
ON
ON ON
LOFF
LHOFF ON
LOFF
L
HH
OFF
ON ON
LOFF
LHOFF ON
LOFF
H
H
H
HH
ON
ON
ON
ON ON
X : Don’t care
3. Protective Functions
＊ Short circuit protection and timer latch
The comparator for short circuit detection in each channel detects the output
voltage level of the power converter. When the output voltage falls below the
short detection level, there will be a constant bias current charging the external
capacitor CSCP that is connected to the CSCP pin until the capacitor voltage level
reaches about 0.7V and the output transistor turned off consequently. The
actuated protection can be reset by restarting the power source.
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
14
＊ Under-voltage lockout protection
The under-voltage lockout protection is triggered when the supply voltage
momentarily drops during transient, which may cause the IC to malfunction. To
prevent such malfunctions, the under-voltage lockout protection circuit will turn
off the output transistor, set the dead time to 100%, and hold the CSCP pin at the
“L” level after detecting a decrease in internal reference voltage with respect to
the power supply voltage,.
＊ Output switch control
When the power is turned on, output switch control circuit (SWIN = “L”) prevents
the reactive current from flowing to external CH5 and CH6. After releasing
UVLO and the C+IN6 pin voltage goes above 0.9V, if SWIN is “H” then SWOUT
becomes “L” to turn on the external MOSFET and generate output voltage.
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
15
4. Soft Start Function
＊ The CTL, CTL1,2, CTL3, CTL4, and CTL5 terminals are driven to high level at
the same time. The driving scheme is described in the following diagram.
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
16
＊ After CH6 soft start and driving the CTL1,2, CTL3, CTL4, and CTL5 to high
level. The driving scheme is described in following diagram.
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
17
＊ Soft start setting (for CH6)
Consider the input voltage and the load current to decide the value of the capacitor
connected to the CIN6 pin. The soft start time Ts(s) until the DC/DC converter
output voltage of CH6 reaches 95% can be calculated by:
Ts(s) = 0.45 * C1(μF)
＊ Soft start setting (for CH1 to CH5)
Ts(s) = 1.25 * CS(μF)
Note : It could be disabled soft start function by floating CIN6 pin or CS pin.
)1(25.1 )(
^
RC
Ts
INC eV −
+−×=
+
=KK
KK
R7545
75*45
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
18
Determine Oscillator Frequency
The triangular oscillator frequency is decided by the timing capacitor (CT) and
timing resistor (RT) according to the following formula:
f
OSC(KHz) = 900000/( RT(KΩ)* CT(pF))
DC/DC Output Voltage
＊ For CH1 to CH3, CH5 and CH6
＊ For CH4
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
19
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
20
The CH6 Source Current
The output circuit of CH6 is illustrated in the following diagram. It can determine
the output source current by defining the value of resistor RB.
Note that the source current can be calculated by the following equation.
Output source current = (VRB/RB) * 210 (A)
Setting Time of Short Circuit Protection
The SCP comparator in each channel detects the output voltage to decide whether the
power converter works at normal condition. At the same time, the voltage level of
CSCP pin is held at low level. If the output load of these converters rapidly
malfunction or become shorted, causing the output voltage to drop, the SCP
comparator detects that and enables short circuit protection. The time period for
short circuit protection is shown in the following equation.
Short detection time (tPE(s))
t
PE(s) = 0.7 * CSCP (μF)
Note : It could be disabled short circuit protection function by connecting CSCP
pin into the ground.
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
21
Setting the Dead Time Control Level
When using step up or Zeta or flyback DC/DC converter, it must prevent that
output transistor works at full-ON state (ON duty = 100%). To prevent this
situation, set the maximum duty of these channels. The dead time control circuit
is implemented as below. When the voltage at the DTC1 pin is higher than the
triangular wave voltage (CT1), the output transistor is turned on. The maximum
duty calculation formula assuming that triangular wave amplitude = 0.7V and
triangular wave minimum voltage = 1.1V.
Note 1 : The circuit is suitable at CH1 to CH5.
Note 2 : Shorting DTC and VREF to disable dead time control function.
Using CH4 Inv Amp.
When not using the CH4 INV Amp., connect the INA4 and OUTA4 each other.
(
)
[
]
%1007.0/1.1
×
−
=
d
VDuty
AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878 WWW: http://www.aimtron.com.tw
Fax: 886-3-563-0879 Email: service@aimtron.com.tw
22
Package Description
LQFP48
