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date 07/14/2015
page 1 of 7
SERIES: PQA50-D │ DESCRIPTION: DC-DC CONVERTER
date
page 1 of 7
FEATURES
• up to 50 W isolated output
• 2:1 input range (18~36 Vdc, 36~75 Vdc)
• smaller package
• single, regulated output
• 1,500 Vdc isolation
• short circuit, over current, input under voltage protection
• remote on/off
• operating temperature range (-40~85°C)
• six sided metal shielding
• efficiency up to 93%
MODEL input
voltage
output
voltage
output
current
output
power
ripple
and noise1
efciency
typ
(Vdc)
range
(Vdc) (Vdc)
min
(mA)
max
(A)
max
(W)
max
(mVp-p)
typ
(%)
PQA50-D24-S3-D 24 18~36 3.3 500 10 33 150 91
PQA50-D24-S5-D 24 18~36 5 500 10 50 150 93
PQA50-D24-S12-D 24 18~36 12 208 4.167 50 150 93
PQA50-D24-S15-D 24 18~36 15 167 3.333 50 150 93
PQA50-D24-S24-D 24 18~36 24 104 2.083 50 150 93
PQA50-D48-S3-D 48 36~75 3.3 500 10 33 150 91
PQA50-D48-S5-D 48 36~75 5 500 10 50 150 93
PQA50-D48-S12-D 48 36~75 12 208 4.167 50 150 93
PQA50-D48-S15-D 48 36~75 15 167 3.333 50 150 93
PQA50-D48-S24-D 48 36~75 24 104 2.083 50 150 93
Notes: 1.Rippleandnoisearemeasuredat20MHzBWby"parallelcable"methodwith1μFceramicand10μFelectrolyticcapacitorsontheoutput.
PART NUMBER KEY
PQA50 - DXX - SXX - DX
Input Voltage
Output Voltage
Packaging Style
Base Number
DIP
Heatsink
"blank" = no heatsink
H = with heatsink
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CUI Inc │ SERIES: PQA50-D │ DESCRIPTION: DC-DC CONVERTER date 07/14/2015 │ page 2 of 7
INPUT
parameter conditions/description min typ max units
operating input voltage 24 Vdc input models
48 Vdc input models
18
36
24
48
36
75
Vdc
Vdc
start-up voltage
input under voltage protection
24 Vdc input models
48 Vdc input models
18
36
Vdc
Vdc
input over voltage protection
24 Vdc input models
48 Vdc input models
36
75
Vdc
Vdc
under/over voltage shutdown
input under voltage protection
24 Vdc input models
48 Vdc input models
16
32
Vdc
Vdc
input over voltage protection
24 Vdc input models
48 Vdc input models
40
81
Vdc
Vdc
surge voltage
for maximum of 1 second
24 Vdc input models
48 Vdc input models
-0.7
-0.7
50
100
Vdc
Vdc
start-up time nominal input, constant load 10 ms
CTRL1
models ON (CTRL open or connect TTL high level, 3~12 Vdc)
modelsOFF(CTRLconnectGNDorlowlevel,0~1.2Vdc)
inputcurrent(modelsOFF) 6 mA
lter pilter
Note1.CTRLpinvoltageisreferencedtoGND.
OUTPUT
parameter conditions/description min typ max units
line regulation full load, input voltage from low to high ±0.2 ±0.5 %
load regulation 10% to 100% load ±0.5 ±1 %
voltage accuracy ±1 ±3 %
adjustability ±10 %
switching frequency PWM mode 300 kHz
transient recovery time 25% load step change 300 500 μs
transient response deviation 25% load step change ±3 ±5 %
temperaturecoefcient 100% load ±0.02 %/°C
PROTECTIONS
parameter conditions/description min typ max units
over voltage protection2
3.3 Vdc output models
5 Vdc output models
12 Vdc output models
15 Vdc output models
24 Vdc output models
3.9
6.2
15
18
30
Vdc
Vdc
Vdc
Vdc
Vdc
over current protection 135 %
short circuit protection continuous, automatic recovery, hiccup
over temperature protection 110 °C
Note 2. Module needs to be re-started after over voltage protection.
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CUI Inc │ SERIES: PQA50-D │ DESCRIPTION: DC-DC CONVERTER date 07/14/2015 │ page 3 of 7
SAFETY AND COMPLIANCE
parameter conditions/description min typ max units
isolation voltage input to output at 1 mA for 1 minute 1,500 Vdc
isolation resistance input to output at 500 Vdc 1,000 MΩ
isolation capacitance input to output at 100 kHz, 0.1 Vdc 2,000 pF
conducted emissions CISPR22/EN55022classB(externalcircuitrequired,seegure1)
radiated emissions CISPR22/EN55022classB(externalcircuitrequired,seegure1)
ESD IEC/EN61000-4-2 class B, contact ± 4kV
radiated immunity IEC/EN61000-4-3 class A, 10V/m
EFT/burst IEC/EN61000-4-4classB,±2kV(externalcircuitrequired,seegure1)
surge IEC/EN61000-4-5classB,±2kV(externalcircuitrequired,seegure1)
conducted immunity IEC/EN61000-4-6 class A, 3 Vr.m.s
voltage dips & interruptions IEC/EN61000-4-29 class B, 0%-70%
MTBF asperMIL-HDBK-217F@25°C 1,000,000 hours
RoHS 2011/65/EU
ENVIRONMENTAL
parameter conditions/description min typ max units
operating temperature see derating curve -40 85 °C
storage temperature -55 125 °C
storage humidity non-condensing 5 95 %
case temperature at full load, operating temperature curve range 105 °C
vibration 10~55 Hz, 30 min. along x, y, and z 10 G
SOLDERABILITY
parameter conditions/description min typ max units
hand soldering 1.5 mm from case for 10 seconds 300 °C
wave soldering seewavesolderingprole 260 °C
MECHANICAL
parameter conditions/description min typ max units
dimensions board mount: 50.80 x 25.40 x 11.80
board mount with heatsink: 50.80 x 25.40 x 16.30
mm
mm
case material aluminum alloy
weight board mount
board mount with heatsink
35
43
g
g
10 Sec. Max.
Wave Soldering Time
4 Sec. Max.
Peak Temp. 260°C Max.
Time (sec.)
Temperature (°C)
250
200
150
100
50
0
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CUI Inc │ SERIES: PQA50-D │ DESCRIPTION: DC-DC CONVERTER date 07/14/2015 │ page 4 of 7
MECHANICAL DRAWING
units: mm[inch]
tolerance: ±0.30[±0.012]
pin diameter tolerance: ±0.10[±0.004]
pin height tolerance: ±0.50[±0.020]
units: mm[inch]
tolerance: ±0.30[±0.012]
pin diameter tolerance: ±0.10[±0.004]
pin height tolerance: ±0.50[±0.020]
∅1.50 [0.059]
4.10 [0.161]
∅1.00[0.039]
11.80
[0.465]
50.80[2.000]
45.72[1.800]
1
2
3
6
5
4
10.16
[0.400]5.08[0.200]
10.16
[0.400]
10.16
[0.400]
25.40[1.000]
6
5
4
1
2
3
Top View
PCB Layout
Front View
Bottom View
Grid Size:
2.54mm x 2.54mm
∅1.50 [0.059]
6
5
4
1
2
3
Top View
PCB Layout
Front View
Top View
Grid Size:
2.54mm x 2.54mm
PIN CONNECTIONS
PIN Function
1 Vin
2GND
3 Ctrl
4 Trim
5 0V
6+Vo
PIN CONNECTIONS
PIN Function
1 Vin
2GND
3 Ctrl
4 Trim
5 0V
6+Vo
BOARD MOUNT
BOARD MOUNT WITH HEATSINK
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CUI Inc │ SERIES: PQA50-D │ DESCRIPTION: DC-DC CONVERTER date 07/14/2015 │ page 5 of 7
OutputVoltage≤5Vdc
Recommended external circuit components
Vin (Vdc) 24 48
C0 330μF/50V 330μF/100V
CY1, CY2 1nF/2kV 1nF/2kV
LCM 2.2mH 2.2mH
EMC RECOMMENDED CIRCUIT
DERATING CURVES
100
80
60
40
20
Ambient Temperature (°C)
Load (%)
-40-20 02040100
Safe operating area
55 65 85
Without heatsink
With heatsink
100
80
60
40
20
Ambient Temperature (°C)
Load (%)
-40-20 0204085 100
Safe operating area
60 70
Without heatsink
With heatsink
Output Voltage > 5Vdc
Figure 1 Table 1
Vin
GND
+Vo
0V
DC/DC
LO
AD
LCM
C0
CY
Vin
GN
D
CY 1
2
Cout
TEST CONFIGURATION
DC
Cin
Lin
DC
Load
Oscilloscope
Current
Probe
Lin(4.7µH) Cin(220µF, ESR<1.0Ωat 100KHz)
Note: 1.Inputreected-ripplecurrentismeasuredwithaninductorLinandCapacitorCintosimulatesourceimpedance.
External components
Lin 4.7μH
Cin 220μF,ESR<1.0Ω
at 100 kHz
Figure 2 Table 2
Note: 1. See Table 3 for Cout values.
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CUI Inc │ SERIES: PQA50-D │ DESCRIPTION: DC-DC CONVERTER date 07/14/2015 │ page 6 of 7
1. Requirement on output load
Toensurethismodulecanoperateefcientlyandreliably,theminimumoutputloadcannotbelessthan5%ofthefullloadduring
operation. If the actual output power is small, please connect a resistor at the output end in parallel to increase the load.
2. Recommended circuit
This series has been tested according to the following recommended testing circuit before leaving the factory. This series should be
testedunderload(seeFigure3).Ifyouwanttofurtherdecreasetheinput/outputripple,youcanincreasecapacitanceproperlyor
choose capacitors with low ESR (see table 3). However, the capacitance must not exceed the maximum capacitive load or a start-up
problem might arise (see table 4).
3. Output Voltage Trimming
Leave open if not used.
FormulaforTrimResistor
Application Circuit for Trim Pin
(part in broken line is the interior of models)
Note: Value for R1, R2, R3, and Vref (see Table 5)
RT: Trim Resistor
a:User-denedparameter,noactualmeanings
Vo': The trim up/down voltage
up:a= Vre
f
Vo’-Vref R
1
R= a
2
R-a
2
-R
3
down:a= Vre
f
Vo’-Vref R
2
R=
T
T
aR
1
R-a
1
-R
3
APPLICATION NOTES
Figure 3
Table 3 Table 4
Table 5
Figure 4
Vout
(Vdc)
Cin
(µF)
Cout
(µF)
3.3 100 220
5 100 220
12 100 100
15 100 100
24 100 47
Notes: 1. Minimum load shouldn't be less than 5%, otherwise ripple may increase dramatically. Operation under minimum load will not damage the converter, however, they may
notmeetallspecicationslisted.
2. Maximum capacitive load is tested at input voltage range and full load.
3.AllspecicationsaremeasuredatTa=25°C,humidity<75%,nominalinputvoltageandratedoutputloadunlessotherwisespecied.
+Vo
0V
R
2
R
1
R
3
V
re f
R
T
Trim
0V
R
2
R
1
R
3
V
ref
R
T
Tr
im
+Vo
Tr im up Tr im down
DC DC
Vin
GND
+Vout
0V
Cin
Vout
(Vdc)
Max.
Capacitive Load
(μF)
3.3 27000
5 18900
12 3700
15 2000
24 1000
Vout
(Vdc)
R1
(kΩ)
R2
(kΩ)
R3
(kΩ)
Vref
(V)
3.3 4.788 2.87 15 1.24
5 2.87 2.87 12.1 2.5
12 11 2.87 22 2.5
15 15 3 22 2.5
24 20 2.308 15 2.5
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CUI Inc │ SERIES: PQA50-D │ DESCRIPTION: DC-DC CONVERTER date 07/14/2015 │ page 7 of 7
CUI offers a two (2) year limited warranty. Complete warranty information is listed on our website.
CUI reserves the right to make changes to the product at any time without notice. Information provided by CUI is believed to be accurate and reliable. However, no responsibility is
assumed by CUI for its use, nor for any infringements of patents or other rights of third parties which may result from its use.
CUI products are not authorized or warranted for use as critical components in equipment that requires an extremely high level of reliability. A critical component is any component of a
life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness.
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20050 SW 112th Ave.
Tualatin, OR 97062
800.275.4899
Fax503.612.2383
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techsupport@cui.com
rev. description date
1.0 initial release 07/01/2013
1.01 added heat sink option, updated spec 10/29/2013
1.02 updated datasheet 07/14/2015
The revision history provided is for informational purposes only and is believed to be accurate.
REVISION HISTORY
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Mouser Electronics
Authorized Distributor
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