Additional Resources: Product Page | 3D Model
datedate 01/03/201401/03/2014
pagepage 1 of 61 of 6
SERIES: VFK400W DESCRIPTION: DC-DC CONVERTER
FEATURES
up to 400 W isolated output
rugged metal enclosure with integrated heat sink
4:1 input range (10~36 Vdc, 18~75 Vdc)
single output from 12~48 Vdc
1,500 Vdc isolation
over current, over temperature, over voltage,
and short circuit protection
remote on/off
efficiency up to 87%
input output output output ripple ef ciency
MODEL
1
voltage voltage current power and noise
range max max max max
(Vdc) (Vdc) (A) (W) (mVp-p) (%)
VFK400W-Q24-S12 10~36 12 33.3 400 200 87
VFK400W-Q24-S24 10~36 24 16.7 400 240 86
VFK400W-Q24-S48 10~36 48 8.3 398 480 86
2
VFK400W-Q48-S12 20~75 12 33.3 400 200 87
VFK400W-Q48-S24 18~75 24 16.7 400 240 86
VFK400W-Q48-S48 18~75 48 8.3 398 480 86.5
Note: 1. Ripple and noise are measured at full load, 20 MHz BW with 10F tantalum capacitor and 1F ceramic capacitor across the output. The 48 Vdc output models require a
22uF aluminum capacitor and a 1uF ceramic capacitor across the output.
2. An external input capacitor of 470uF is recommended to reduce input ripple voltage.
PART NUMBER KEY
VFK400W - QXX - SXX
Base Number Input Voltage Output Voltage
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CUI Inc SERIES: VFK400W DESCRIPTION: DC-DC CONVERTER date 01/03/2014 page 2 of 6
INPUT
parameter conditions/description min typ max units
24 Vdc input 10 24 36 Vdc
operating input voltage
12 Vdc output model 20 48 75 Vdc
48 Vdc input
24/48 Vdc output models 18 48 75 Vdc
power up 9.5 Vdc
24 Vdc input
power down 8.5 Vdc
under voltage shutdown
power up 17.8 Vdc
48 Vdc input
power down 15.5 Vdc
models ON (>3.5 Vdc or open circuit)
1
CTRL positive logic
models OFF (0~1.2 Vdc)
lter pi lter
Note: 1. Open collector refer to -Vin
OUTPUT
parameter conditions/description min typ max units
maximum output capacitance for all models 2,200 F
line regulation measured from high line to low line 1 %
load regulation measured from full load to zero load 1 %
voltage accuracy 1.5 %
adjustability 90 105 %
switching frequency 250 kHz
transient response 25% step load change 500 s
temperature coef cient 0.03 %/C
PROTECTIONS
parameter conditions/description min typ max units
short circuit protection continuous
over current protection % nominal output current 110 150 %
over voltage protection 115 140 %
over temperature protection shutdown 110 C
SAFETY AND COMPLIANCE
parameter conditions/description min typ max units
for 1 minute: input to output; input to case;
isolation voltage 1,500 Vdc
output to case
isolation resistance 10 M
RoHS 2011/65/EU (CE)
ENVIRONMENTAL
parameter conditions/description min typ max units
operating temperature see derating curves -40 85 C
storage temperature -55 105 C
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