Additional Resources: Product Page 3D Model datdatee 09/13/202109/13/2021 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 efficiency 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 cui.comAdditional Resources: Product Page 3D Model CUI Inc SERIES: VFK400W DESCRIPTION: DC-DC CONVERTER date 09/13/2021 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 (open circuit) 1 CTRL positive logic models OFF (0~1.2 Vdc) filter pi filter Note: 1. Do not drive high, may damage device. 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 coefficient 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 cui.com