T
Technical
echnical
S
Specification
pecification
PQ24050QGA20
PQ24050QGA20
Product # PQ24050QGA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2QG250D Rev. C 03/13/06 Page 1
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.
PQ24050QGA20 Module
24V
24Vin
in 5V
5Vout
out 20Amp
20Amp 2000Vdc
2000Vdc Quar
Quarter-brick
ter-brick
Input
Input Output
Output Current
Current Isolation
Isolation DC/DC Conver
DC/DC Converter
ter
Ultra-high efficiency, 87% at full rated load current
Delivers up to 20 amps of output current (100 Watts)
with minimal derating
Wide input voltage range: 18V – 36V meets or
exceeds all 24V bus standards
Fixed frequency switching provides predictable EMI per-
formance
No minimum load requirement means no preload resis-
tors required
Operational Features
Operational Features
Industry standard quarter-brick pin-out configuration
Industry standard size: 1.45” x 2.3” (36.8x58.4mm)
Total height less than 0.40” (10.2mm), permits better
airflow and smaller card pitch
Total weight: 1.2 oz. (34 grams)
Flanged pins designed to permit surface mount solder-
ing (to avoid wave solder) using FPiP technique
Mechanical Features
Mechanical Features
On/Off control referenced to input side (positive and
negative logic options are available)
Remote sense for the output voltage compensates for
output distribution drops
Output voltage trim permits custom voltages and voltage
margining
Contr
Control Features
ol Features
Input under-voltage lockout disables converter at low
input voltage conditions
Output current limit and short circuit protection protects
converter and load from damage
Active back bias limit prevents damage to converter
from external load induced pre-bias
Output over-voltage protection
Thermal shutdown
Pr
Protection Features
otection Features
2000V, 30 Minput-to-output isolation
UL/cUL 60950-1 recognized (US & Canada), basic
insulation rating
TUV certified to EN60950-1
Meets 72/23/EEC and 93/68/EEC directives
Meets UL94V-0 flammability requirements
NEBS and ETSI compliant
Safety Features
Safety Features
Product # PQ24050QGA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2QG250D Rev. C 03/13/06 Page 2
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
18-36 V
18-36 V
5 V
5 V
20 A
20 A
Quarter-brick
Quarter-brick
Pin No. Name Function
1 Vin(+) Positive input voltage
2ON/OFF TTL input to turn converter
on and off, referenced to
Vin(-), with internal pull up.
3 Vin(-) Negative input voltage
4 Vout(-) Negative output voltage
5SENSE(-) Negative remote sense1
6TRIM Output voltage trim2
7 SENSE(+) Positive remote sense3
8 Vout(+) Positive output voltage
Notes:
1. SENSE(-) may be connected to Vout(-) or left open.
2. Leave TRIM pin open for nominal output voltage.
3. SENSE(+) may be connected to Vout(+) or left open.
NOTES
1) Pins 1-3, 5-7 are 0.040” (1.02mm) diameter with
0.080” (2.03 mm) diameter standoff shoulders.
2) Pins 4 and 8 are 0.062” (1.57 mm) diameter with
0.100” (2.54 mm) diameter standoff shoulders.
3) Other pin extension lengths available. Recommended pin
length is 0.03” (0.76mm) greater than the PCB thickness.
4) All Pins: Material - Copper Alloy
Finish - Tin/Lead over Nickel plate
5) Undimensioned components are shown for visual
reference only.
6) All dimensions in inches (mm)
Tolerances: x.xx +/-0.02 in. (x.x +/-0.5mm)
x.xxx +/-0.010 in. (x.xx +/-0.25mm)
7) Weight: 1.2 oz. (34 g) typical
8) Workmanship: Meets or exceeds IPC-A-610C Class II
9)
UL/TUV standards require a clearance greater than 0.04”
(1.02mm) between input and output for Basic insulation. This
issue should be considered if any copper traces are on the top
side of the user’s board. Note that the ferrite cores are considered
part of the input/primary circuit.
10) The flanged pins are designed to permit surface mount sol-
dering (allowing to avoid the wave soldering process)
through the use of the flanged pin-in-paste technique.
0.300
(7.62)
0.600
(15.24)
1.45
(36.8)
0.43
(10.9)
0.150
(3.81)
0.300
(7.62)
0.450
(11.43) 0.600
(15.24)
0.14
(3.6)
2.30
(58.4)
2.00
(50.8)
Top View
Side View
PIN DESIGNATIONS
MECHANICAL
DIAGRAM
Load Board
Bottom side
Clearance
See Note 9
Max. Height
Lowest
Component
0.40
(10.2)
0.047+/-0.015
(1.19+/-0.38)
0.145
(3.68)
See Note 3
Flanged Pin
See Note 10
Product # PQ24050QGA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2QG250D Rev. C 03/13/06 Page 3
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
18-36 V
18-36 V
5 V
5 V
20 A
20 A
Quarter-brick
Quarter-brick
Parameter
Min. Typ. Max. Units Notes & Conditions
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Non-Operating 50 V Continuous
Operating 40 V Continuous
Operating Transient Protection
50 V
<10
µs, 1% duty cycle
Isolation Voltage (input to output) 2000 V Basic insulation, Pollution Degree 2
Operating Temperature -40 100
°C
Storage Temperature -55 125
°C
Voltage at ON/OFF input pin -2 18 V
INPUT CHARACTERISTICS
Operating Input Voltage Range 18 24 36 V
Input Under-Voltage Lockout
Turn-On Voltage Threshold 15.5 16 16.5 V
Turn-Off Voltage Threshold 14.0 14.5 15.0 V
Lockout Voltage Hysteresis 1.0 1.5 2.0 V
Maximum Input Current 6.4 A 100% Load, 18 Vin
No-Load Input Current 100 200 mA
Disabled Input Current 1.6 3 mA
Inrush Current Transient Rating 0.01 A2s
Input Reflected Ripple Current 10 mA P-P thru 3.3
µH inductor;
Figures
13 & 15
Input Terminal Ripple Current 200 mA RMS
;
Figures
13 & 14
Recommended Input Fuse 20 A Fast blow external fuse recommended
Input Filter Component Values (C\L) 4.5\1.5
µF\µH Internal values; see Figure E
Recommended External Input Capacitance 100
µF Typical ESR 0.1-0.2
, see Figure 13
OUTPUT CHARACTERISTICS
Output Voltage Set Point 4.95 5.00 5.05 V
Output Voltage Regulation
Over Line +0.05 \ 2 +0.2 \ 10 %\mV
Over Load +0.05 \ 2 +0.2 \ 10 %\mV
Over Temperature +25 +75 mV
Total Output Voltage Range 4.87 5.13 VOver sample, line, load, temperature & life
Output Voltage Ripple and Noise120MHz bandwidth; Figures
13
& 16
Peak-to-Peak 25 50 mV Full Load; see Figures
13
& 16
RMS 612 mV Full Load; see Figures
13
& 16
Operating Output Current Range 020 ASubject to thermal derating; Figures
5 - 8
Output DC Current-Limit Inception 21 24 26 AOutput Voltage 10% Low; Figure 17
Output DC Current-Limit Shutdown Voltage 3.1 V
Back-Drive Current Limit while Enabled 0.3 0.65 1.5 A Negative current drawn from output
Back-Drive Current Limit while Disabled 0 10 50 mA Negative current drawn from output
Maximum Output Capacitance 6,000
µF
5.0Vout at 20A Resistive Load
DYNAMIC CHARACTERISTICS
Input Voltage Ripple Rejection 66 dB 120 Hz; Figure 20
Output Voltage During Load Current Transient
For a Step Change in Output Current (0.1A/µs) 220 mV 50% to 75% to 50% Iout max; Figure 11
For a Step Change in Output Current (5A/µs) 240 mV 50% to 75% to 50% Iout max; Figure 12
Settling Time 400 µs To within 1% Vout nom
Turn-On Transient
Turn-On Time 1 4 8 ms Full load, Vout=90% nom.; Figures 9 & 10
Start-Up Inhibit Time 180 200 240 ms
-40°C to +125°C; Figure F
Output Voltage Overshoot 0 % 10,000 µF load capacitance, Iout = 0A
EFFICIENCY
100% Load 87 % Figures 1 - 4
50% Load 90 % Figures 1 - 4
TEMPERATURE LIMITS FOR POWER DERATING CURVES
Semiconductor Junction Temperature 125 °C Package rated to 150°C
Board Temperature 125 °C UL rated max operating temp 130°C
Transformer Temperature 125 °C See Figures 5 - 8 for derating curves
ISOLATION CHARACTERISTICS
Isolation Voltage (dielectric strength) 2000 V
Isolation Resistance 30 M
Isolation Capacitance
2
470 pF
PQ24050QGA20 ELECTRICAL CHARACTERISTICS
TA=25°C, airflow rate=300 LFM, Vin=24Vdc unless otherwise noted; full operating temperature range is -40°C to +100°C ambient tem-
perature with appropriate power derating.
Specifications subject to change without notice.
Note 1: For applications requiring reduced output voltage ripple and noise, consult SynQor applications support (e-mail: support@synqor.com)
Note 2: Higher values of isolation capacitance can be added external to the module.
Product # PQ24050QGA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2QG250D Rev. C 03/13/06 Page 4
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
18-36 V
18-36 V
5 V
5 V
20 A
20 A
Quarter-brick
Quarter-brick
Parameter
PMin. Typ. Max. Units Notes & Conditions
FEATURE CHARACTERISTICS
Buck Stage Switching Frequency 280 300 320 kHz
Isolation Stage Switching Frequency1175 kHz
ON/OFF Control (Option P)
Off-State Voltage -2 0.8 V
On-State Voltage 2.4 18 V
ON/OFF Control (Option N)
Off-State Voltage 2.4 18 V
On-State Voltage -2 0.8 V
ON/OFF Control (Either Option) Figures A
&B
Pull-Up Voltage Vin/3 9.6 V
Pull-Up Resistance 33 k
Output Voltage Trim Range -20 +10 % Measured across Pins 8 & 4; Figure C
Output Voltage Remote Sense Range +10 % Measured across Pins 8 & 4
Output Over-Voltage Protection 117 122 127 % Over full temp range; % of nominal Vout
Over-Temperature Shutdown 125 °C Average PCB Temperature
Over-Temperature Shutdown Restart Hysteresis 10 °C
Load Current Scale Factor 1000
RELIABILITY CHARACTERISTICS
Calculated MTBF (Telcordia) 2.8 106Hrs. TR-NWT-000332; 80% load,300LFM, 40oC Ta
Calculated MTBF (MIL-217) 1.8 106Hrs. MIL-HDBK-217F; 80% load, 300LFM, 40oC Ta
Field Demonstrated MTBF 106Hrs. See our website for details
1. The shape of the output voltage ripple waveform is effected by the fact that the isolation stage runs asynchronous to the input stage.
STANDARDS COMPLIANCE
Parameter
PNotes
STANDARDS COMPLIANCE
UL/cUL 60950-1 File # E194341, Basic insulation & pollution degree 2
EN60950-1 Certified by TUV
72/23/EEC
93/68/EEC
Needle Flame Test (IEC 695-2-2) Test on entire assembly; board & plastic components UL94V-0 compliant
IEC 61000-4-2 ESD test, 8kV - NP, 15kV air - NP (Normal Performance)
GR-1089-CORE Section 7 - electrical safety, Section 9 - bonding/grounding
An external input fuse must always be used to meet these safety requirements. Contact SynQor for official safety
certificates on new releases or download from the SynQor website.
QUALIFICATION TESTING
Parameter
P# Units Test Conditions
QUALIFICATION TESTING
Life Test 32 95% rated Vin and load, units at derating point, 1000 hours
Vibration 5 10-55Hz sweep, 0.060” total excursion,1 min./sweep, 120 sweeps for 3 axis
Mechanical Shock 5 100g minimum, 2 drops in x and y axis, 1 drop in z axis
Temperature Cycling 10 -40°C to 100°C, unit temp. ramp 15°C/min., 500 cycles
Power/Thermal Cycling 5 Toperating = min to max, Vin = min to max, full load, 100 cycles
Design Marginality 5Tmin-10°C to Tmax+10°C, 5°C steps, Vin = min to max, 0-105% load
Humidity 5 85°C, 85% RH, 1000 hours, 2 minutes on and 6 hours off
Solderability 15 pins MIL-STD-883, method 2003
Extensive characterization testing of all SynQor products and manufacturing processes is performed to ensure that we supply
robust, reliable product. Contact the factory for official product family qualification documents.
ELECTRICAL CHARACTERISTICS (Continued)
OPTIONS
SynQor provides various options for Logic Sense, Pin Length and
Feature Set for this family of DC/DC converters. Please consult the
last page of this specification sheet for information on available
options.
PATENTS
SynQor is protected under various patents, including but not lim-
ited to U.S. Patent # 5,999,417.
Product # PQ24050QGA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2QG250D Rev. C 03/13/06 Page 5
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
18-36 V
18-36 V
5 V
5 V
20 A
20 A
Quarter-brick
Quarter-brick
60
65
70
75
80
85
90
95
0 2 4 6 8 10 12 14 16 18 20
Load Cur rent (A)
Efficiency (%)
18Vin
24Vin
36Vin
Figure 1: Efficiency at nominal output voltage vs. load current for min-
imum, nominal, and maximum input voltage at 25
°
C.
82
83
84
85
86
87
88
89
90
0 100 200 300 400 500
Air Flow (LFM)
Efficiency (%)
25 C
40 C
55 C
Figure 2: Efficiency at nominal output voltage and 60% rated power vs.
airflow rate for ambient air temperatures of 25
°
C, 40
°
C, and 55
°
C
(nominal input voltage).
0
2
4
6
8
10
12
14
16
18
0 2 4 6 8 10 12 14 16 18 20
Load Cur rent (A)
Power Dissipation (W)
18Vin
24Vin
36Vin
Figure 3: Power dissipation at nominal output voltage vs. load current
for minimum, nominal, and maximum input voltage at 25
°
C.
6.0
6.5
7.0
7.5
8.0
8.5
9.0
9.5
10.0
0 100 200 300 400 500
Power Dissipation (W)
25 C
40 C
55 C
Figure 4: Power dissipation at nominal output voltage and 60% rated
power vs. airflow rate for ambient air temperatures of 25
°
C, 40
°
C, and
55
°
C (nominal input voltage).
0
2
4
6
8
10
12
14
16
18
20
025 40 55 70 85
Ambient Air Temperature (oC)
Iout (A)
400 LF M (2. 0 m/ s)
300 LF M (1. 5 m/ s)
200 LFM (1. 0 m/s)
100 LFM (0. 5 m/s)
0 LFM (0 m/ s)
Figure 5: Maximum output power derating curves vs. ambient air tem-
perature for airflow rates of 0 LFM through 400 LFM with air flowing
from pin 1 to pin 3 (nominal input voltage).
Figure 6: Thermal plot of converter at 14 amp load current (70W) with
55
°
C air flowing at the rate of 200 LFM. Air is flowing across the con-
verter from pin 1 to pin 3 (nominal input voltage).
Semiconductor junction temperature is
within 1
°
C of surface temperature
Product # PQ24050QGA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2QG250D Rev. C 03/13/06 Page 6
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
18-36 V
18-36 V
5 V
5 V
20 A
20 A
Quarter-brick
Quarter-brick
0
2
4
6
8
10
12
14
16
18
20
0 25 40 55 70 85
Ambient Air Temperature (oC)
Iout (A)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
0 LFM (0 m/s)
Figure 7: Maximum output power-derating curves vs. ambient air tem-
perature for airflow rates of 0 LFM through 400 LFM with air flowing
from input to output (nominal input voltage).
Figure 8: Thermal plot of converter at 14 amp load current (70W) with
55
°
C air flowing at the rate of 200 LFM. Air is flowing across the con-
verter from input to output (nominal input voltage).
Figure 9: Turn-on transient at full load (resistive load) (2 ms/div).
Input voltage pre-applied. Ch 1: Vout (2V/div). Ch 2: ON/OFF input
(5V/div)
Figure 10: Turn-on transient at zero load (2 ms/div).
Ch 1: Vout (2V/div)
Ch 2: ON/OFF input (5V/div)
Figure 11: Output voltage response to step-change in load current (50%-75%-
50% of Iout(max); dI/dt = 0.1A/
µ
s). Load cap: 10
µ
F, 100 m
ESR tantalum capac-
itor and 1
µ
F ceramic capacitor. Ch 1: Vout (200mV/div), Ch 2: Iout (10A/div).
Figure 12: Output voltage response to step-change in load current (50%-75%-
50% of Iout(max): dI/dt = 5A/
µ
s). Load cap: 470
µ
F, 30 m
ESR tantalum
capacitor and 1
µ
F ceramic cap. Ch 1: Vout (200mV/div), Ch 2: Iout (10A/div).
Semiconductor junction temperature is
within 1
°
C of surface temperature
Product # PQ24050QGA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2QG250D Rev. C 03/13/06 Page 7
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
18-36 V
18-36 V
5 V
5 V
20 A
20 A
Quarter-brick
Quarter-brick
Figure 14: Input Terminal Ripple Current, ic, at full rated output cur-
rent and nominal input voltage with 3.3
µ
H source impedance and
100
µ
F electrolytic capacitor (500 mA/div). See Figure 13.
Figure 15: Input reflected ripple current, is, through a 3.3
µ
H source
inductor at nominal input voltage and rated load current (20 mA/div).
See Figure 13.
Figure 16: Output voltage ripple at nominal input voltage and rated
load current (20 mV/div). Load capacitance: 1
µ
F ceramic capacitor
and 10
µ
F tantalum capacitor. Bandwidth: 20 MHz. See Figure 13.
Figure 13: Test set-up diagram showing measurement points for Input
Terminal Ripple Current (Figure 14), Input Reflected Ripple Current
(Figure 15) and Output Voltage Ripple (Figure 16).
0
1
2
3
4
5
6
7
8
02.5 57.5 10 12.5 15 17.5 20 22.5 25
Load Curr ent (A)
Output Voltage (V)
18 V
24 V
36 V
Figure 17: Output voltage vs. load current showing typical current limit
curves and converter shutdown points. Figure 18: Load current (20A/div) as a function of time when the con-
verter attempts to turn on into a 10 m
short circuit. Bottom trace
(2.5ms/div) is an expansion of the on-time portion of the top trace.
3.3
µ
H
source
impedance
DC/DC
Converter
See Fig. 15
See Fig. 14
See Fig. 16
1
µ
F
ceramic
capacitor
10
µ
F,
100m
ESR
tantalum
capacitor
100
µ
F,
0.33
ESR
electrolytic
capacitor
VSOURCE
iSiCVOUT
Product # PQ24050QGA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2QG250D Rev. C 03/13/06 Page 8
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
18-36 V
18-36 V
5 V
5 V
20 A
20 A
Quarter-brick
Quarter-brick
0.001
0.01
0.1
1
10 100 1,000 10,000 100,000
Hz
Output Impedance (
)
18 Vin
24 Vin
36 Vin
Figure 19: Magnitude of incremental output impedance (Zout =
vout/iout) for minimum, nominal, and maximum input voltage at full
rated power.
-80
-70
-60
-50
-40
-30
-20
-10
0
10 100 1,000 10,000 100,000
Hz
Forward Transmission (dB)
18 Vin
24 Vin
36 Vin
Figure 20: Magnitude of incremental forward transmission (FT =
vout/vin) for minimum, nominal, and maximum input voltage at full
rated power.
-60
-50
-40
-30
-20
-10
0
10 100 1,000 10,000 100,000
Hz
Reverse Transmission (dB)
18 Vin
24 Vin
36 Vin
Figure 21: Magnitude of incremental reverse transmission (RT =
iin/iout) for minimum, nominal, and maximum input voltage at full rated
power.
0.1
1
10
100
10 100 1,000 10,000 100,000
Hz
Input Impedance (
)
18 Vin
24 Vin
36 Vin
Figure 22: Magnitude of incremental input impedance (Zin = vin/iin)
for minimum, nominal, and maximum input
voltage at full rated power.
Product # PQ24050QGA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2QG250D Rev. C 03/13/06 Page 9
T
Technical S
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pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
18-36 V
18-36 V
5 V
5 V
20 A
20 A
Quarter-brick
Quarter-brick
BASIC OPERATION AND FEATURES
The PowerQor series converter uses a two-stage power conver-
sion topology. The first stage is a buck-converter that keeps the
output voltage constant over variations in line, load, and temper-
ature. The second stage uses a transformer to provide the func-
tions of input/output isolation and voltage step-down to achieve
the low output voltage required.
Both the first stage and the second stage switch at a fixed fre-
quency for predictable EMI performance. Rectification of the
transformer’s output is accomplished with synchronous rectifiers.
These devices, which are MOSFETs with a very low on-state resis-
tance, dissipate far less energy than Schottky diodes. This is the
primary reason that the PowerQor converter has such high effi-
ciency, even at very low output voltages and very high output cur-
rents.
Dissipation throughout the converter is so low that it does not
require a heatsink for operation. Since a heatsink is not required,
the PowerQor converter does not need a metal baseplate or pot-
ting material to help conduct the dissipated energy to the
heatsink. The PowerQor converter can thus be built more simply
and reliably using high yield surface mount techniques on a PCB
substrate.
The PowerQor series of half-brick and quarter-brick converters
uses the industry standard footprint and pin-out configuration.
CONTROL FEATURES
REMOTE ON/OFF (Pin 2): The ON/OFF input, Pin 2, permits
the user to control when the converter is on or off. This input is
referenced to the return terminal of the input bus, Vin(-). There
are two versions of the converter that differ by the sense of the
logic used for the ON/OFF input.
In the positive logic version, the ON/OFF input is active high
(meaning that a high turns the converter on). In the negative logic
version, the ON/OFF signal is active low (meaning that a low
turns the converter on). Figure A details five possible circuits for
driving the ON/OFF pin. Figure B is a detailed look of the inter-
nal ON/OFF circuitry.
REMOTE SENSE(+) (Pins 7 and 5): The SENSE(+) inputs cor-
rect for voltage drops along the conductors that connect the con-
verter’s output pins to the load.
Pin 7 should be connected to Vout(+) and Pin 5 should be con-
nected to Vout(-) at the point on the board where regulation is
desired. A remote connection at the load can adjust for a voltage
drop only as large as that specified in this datasheet, that is
[Vout(+) - Vout(-)][Vsense(+) - Vsense(-)]<
Sense Range % x Vout
Pins 7 and 5 must be connected for proper regulation of the out-
put voltage. If these connections are not made, the converter will
deliver an output voltage that is slightly higher than its specified
value.
Note: the output over-voltage protection circuit senses the voltage
Open Collector Enable Circuit
Figure A: Various circuits for driving the ON/OFF pin. Figure B: Internal ON/OFF pin circuitry
Remote Enable Circuit
Direct Logic Drive
Negative Logic
(Permanently Enabled)
Positive Logic
(Permanently Enabled)
ON/OFF
Vin(_)
ON/OFF
ON/OFF
Vin(_)
ON/OFF
5V
TTL/
CMOS
Vin(_)
ON/OFF
Vin(_)
Vin(_)
TTL
5V
50k
100k
Vin(+)
ON/OFF
Vin(_)
50k
100pF
Product # PQ24050QGA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2QG250D Rev. C 03/13/06 Page 10
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Technical S
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pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
18-36 V
18-36 V
5 V
5 V
20 A
20 A
Quarter-brick
Quarter-brick
across the output (pins 8 and 4) to determine when it should trig-
ger, not the voltage across the converter’s sense leads (pins 7
and 5). Therefore, the resistive drop on the board should be
small enough so that output OVP does not trigger, even during
load transients.
OUTPUT VOLTAGE TRIM (Pin 6): The TRIM input permits the
user to adjust the output voltage across the sense leads up or
down according to the trim range specifications.
To decrease the output voltage, the user should connect a resistor
between Pin 6 and Pin 5 (SENSE(-) input). For a desired decrease
of the nominal output voltage, the value of the resistor should be
Rtrim-down =
(
511
)
- 10.22 (k)
%
where
∆% =Vnominal – Vdesired x100%
Vnominal
To increase the output voltage, the user should connect a resistor
between Pin 6 and Pin 7 (SENSE(+) input). For a desired increase
of the nominal output voltage, the value of the resistor should be
Figure C graphs the relationship between the trim resistor value
and Rtrim-up and Rtrim-down, showing the total range the output
voltage can be trimmed up or down.
Figure C: Trim Graph for 5.0Vout module
Note: the TRIM feature does not affect the voltage at which the
output over-voltage protection circuit is triggered. Trimming the
output voltage too high may cause the over-voltage protection cir-
cuit to engage, particularly during transients.
It is not necessary for the user to add capacitance at the Trim pin.
The node is internally bypassed to eliminate noise.
Total DC Variation of Vout: For the converter to meet its full
specifications, the maximum variation of the DC value of Vout,
due to both trimming and remote load voltage drops, should not
be greater than that specified for the output voltage trim range.
PROTECTION FEATURES
Input Under-Voltage Lockout: The converter is designed to
turn off when the input voltage is too low, helping avoid an input
system instability problem, described in more detail in the appli-
cation note titled “Input System Instability”. The lockout circuitry
is a comparator with DC hysteresis. When the input voltage is ris-
ing, it must exceed the typical Turn-On Voltage Threshold value
(listed on the specification page) before the converter will turn
on. Once the converter is on, the input voltage must fall below
the typical Turn-Off Voltage Threshold value before the converter
will turn off.
Output Current Limit: The maximum current limit remains con-
stant as the output voltage drops. However, once the impedance
of the short across the output is small enough to make the output
voltage drop below the specified Output DC Current-Limit
Shutdown Voltage, the converter turns off.
The converter then enters a “hiccup mode” where it repeatedly
turns on and off at a 5 Hz (nominal) frequency with a 5% duty
cycle until the short circuit condition is removed. This prevents
excessive heating of the converter or the load board.
Output Over-Voltage Limit: If the voltage across the output
pins exceeds the Output Over-Voltage Protection threshold, the
converter will immediately stop switching. This prevents damage
to the load circuit due to 1) excessive series resistance in output
current path from converter output pins to sense point, 2) a
release of a short-circuit condition, or 3) a release of a current
limit condition. Load capacitance determines exactly how high
the output voltage will rise in response to these conditions. After
200 ms the converter will automatically restart.
Over-Temperature Shutdown: A temperature sensor on the
converter senses the average temperature of the module. The
thermal shutdown circuit is designed to turn the converter off
when the temperature at the sensed location reaches the Over-
Temperature Shutdown value. It will allow the converter to turn on
again when the temperature of the sensed location falls by the
amount of the Over-Temperature Shutdown Restart Hysteresis
value.
Rtrim-up
(k
)
)
where
VOUT = Nominal Output Voltage
= (
_511 _10.22
5.11VOUT(100+
%)
1.225%%
10
100
1,000
10,000
100,000
0246810 12 14 16 18 20
Trim Resistance (kOhms)
% increase Vout % decrease Vout
Product # PQ24050QGA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2QG250D Rev. C 03/13/06 Page 11
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
18-36 V
18-36 V
5 V
5 V
20 A
20 A
Quarter-brick
Quarter-brick
APPLICATION CONSIDERATIONS
Input System Instability: This
condition can occur because
any DC/DC converter appears incrementally as a negative
resistance load. A detailed application note titled “Input
System Instability” is available on the SynQor website which
provides an understanding of why this instability arises, and
shows the preferred solution for correcting it.
Application Circuits: Figure D below provides a typical cir-
cuit diagram which details the input filtering and voltage trim-
ming.
Input Filtering and External Capacitance: Figure E below
provides a diagram showing the internal input filter components.
This filter dramatically reduces input terminal ripple current,
which otherwise could exceed the rating of an external elec-
trolytic input capacitor. The recommended external input capac-
itance is specified in the “Input Characteristics” section on the
Electrical Specifications page. More detailed information is
available in the application note titled “EMI Characteristics” on
the SynQor website.
Vin External
Input
Filter
Trim
Vin(+)
Iload
Cload
L
C
Vout(+)
Rtrim-up
or
Rtrim-down
Vsense(+)
ON/OFF
Vin(_)
Vin(+)
Vin(_)
Vout(_)
Vsense(_)
Electrolytic
Capacitor
100µF
Figure D: Typical application circuit (negative logic unit, permanently enabled).
Figure E: Internal Input Filter Diagram (component values listed on specifications page).
Product # PQ24050QGA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2QG250D Rev. C 03/13/06 Page 12
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
18-36 V
18-36 V
5 V
5 V
20 A
20 A
Quarter-brick
Quarter-brick
Startup Inhibit Period: The Startup Inhibit Period ensures that
the converter will remain off for at least 200ms when it is shut
down for any reason. When an output short is present, this gen-
erates a 5Hz "hiccup mode," which prevents the converter from
overheating. In all, there are seven ways that the converter can
be shut down, initiating a Startup Inhibit Period:
• Input Under-Voltage Lockout
• Input Over-Voltage Shutdown (not present in Quarter-brick)
• Output Over-Voltage Protection
• Over Temperature Shutdown
• Current Limit
• Short Circuit Protection
• Turned off by the ON/OFF input
Figure F shows three turn-on scenarios, where a Startup Inhibit
Period is initiated at t0, t1, and t2:
Before time t0, when the input voltage is below the UVL threshold,
the unit is disabled by the Input Under-Voltage Lockout feature.
When the input voltage rises above the UVL threshold, the Input
Under-Voltage Lockout is released, and a Startup Inhibit Period is
initiated. At the end of this delay, the ON/OFF pin is evaluated,
and since it is active, the unit turns on.
At time t1, the unit is disabled by the ON/OFF pin, and it cannot
be enabled again until the Startup Inhibit Period has elapsed.
When the ON/OFF pin goes high after t2, the Startup Inhibit
Period has elapsed, and the output turns on within the typical
Turn-On Time.
RoHS Compliance: The EU led RoHS (Restriction of Hazardous
Substances) Directive bans the use of Lead, Cadmium,
Hexavalent Chromium, Mercury, Polybrominated Biphenyls
(PBB), and Polybrominated Diphenyl Ether (PBDE) in Electrical
and Electronic Equipment. This product is available as 5/6 or
6/6 RoHS compliant. For more information please visit our RoHS
Compliance / Lead Free Initiative web or e-mail us at
RoHS@synqor.com.
Under-Voltage
Lockout Turn-On
Threshold
ON/OFF
(pos logic)
Figure F: Startup Inhibit Period (turn-on time not to scale)
Vout
Vin
200ms 200ms
200ms
(typical start-up
inhibit period)
t0t1t2t
4ms (typical
turn on time)
ON ON ON
OFF OFF
Product # PQ24050QGA20 Phone 1-888-567-9596 www.synqor.com Doc.# 005-2QG250D Rev. C 03/13/06 Page 13
T
Technical S
echnical S pecification
pecification
Input:
Input:
Output:
Output:
Current:
Current:
P
Package:
ackage:
18-36 V
18-36 V
5 V
5 V
20 A
20 A
Quarter-brick
Quarter-brick
PART NUMBERING SYSTEM
The part numbering system for SynQor’s PowerQor DC/DC
converters follows the format shown in the example below.
The first 12 characters comprise the base part number and the
last 3 characters indicate available options. Although there
are no default values for enable logic and pin length, the most
common options are negative logic and 0.145” pins. These
part numbers are more likely to be readily available in stock
for evaluation and prototype quantities.
Application Notes
A variety of application notes and technical white papers can
be downloaded in pdf format from our website.
ORDERING INFORMATION
The tables below show the valid model numbers and ordering
options for converters in this product family. When ordering
SynQor converters, please ensure that you use the complete
15 character part number consisting of the 12 character base
part number and the additional 3 characters for options. To
order 6/6 RoHS compliant product please add a “-G” suffix.
The following option choices must be included in place of the
x y z spaces in the model numbers listed above.
Output Max Output
Voltage Current
PQ24018QGA25xyz 18 - 36 V 1.8 V 25 A
PQ24033QGA25xyz 18 - 36 V 3.3 V 25 A
PQ24050QGA20xyz 18 - 36 V 5.0 V 20 A
PQ24120QGA08xyz 18 - 36 V 12 V 8.3 A
PQ24150QGA07xyz 18 - 36 V 15 V 6.7 A
Model Number
Input Voltage
Enable Pin Feature
Logic Length Set
P - Positive
N - Negative
K - 0.110"
N - 0.145"
R - 0.180"
Y - 0.250"
S - Standard
Options Description: x y z
PQ 24 050 Q G A 20 N N S
Product Family
Package Size
Performance Level
Thermal Design
Output Current
Options (see
Ordering Information)
Input Voltage
Output Voltage
Warranty
SynQor offers a three (3) year limited warranty. Complete warranty
information is listed on our website or is available upon request from
SynQor.
Information furnished by SynQor is believed to be accurate and reliable.
However, no responsibility is assumed by SynQor for its use, nor for any
infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any
patent or patent rights of SynQor.
Contact SynQor for further information:
Phone: 978-849-0600
Toll Free: 888-567-9596
Fax: 978-849-0602
E-mail: power@synqor.com
Web: www.synqor.com
Address: 155 Swanson Road
Boxborough, MA 01719
USA