XRSB-40U_11 Datasheet, PDF (6/21 Pages) Bel Fuse Inc. – ISOLATED DC/DC CONVERTERS

ISOLATED DC/DC CONVERTERS
24 Vdc/48 Vdc Input 1.2 Vdc - 12 Vdc / 18 A - 3.5 A Outputs, 1/16 Brick
Converter
Apr. 07, 2011
Bel Power Inc., a subsidiary of Bel Fuse Inc.
Output Trim Equations
Equations for calculating the trim resistor are shown below (Unit: kΩ). The Trim Down resistor should be
connected between the Trim pin and Ground pin. The Trim Up resistor should be connected between the Trim
pin and the Vout. Only one of the resistors should be used for any given application.
1) Trim Equations for Vo=1.2 V
R_trimdown

511
delta
 10.22
R_trimup

(100

delta) Vo  5.11 
0.6125  delta
313
 10.22
Note:
delta  ^{Vo _ req  Vo} 100%
Vo
Vo_req=Desired (trimmed) output voltage [V] Vo=1.202 V
Module
Module
Vo
Trim
GND
Rtrimdown
Vo
Trim
Rtrimup
GND
2) Trim Equations for Vo=1.5 V - 12 V
R_trimdown

511
delta
 10.22
R_trimup

(100

delta) Vo  511
1.225 delta
626
 10.22
Note: _{delta  Vo _ req Vo  100%}
Vo
Vo_req=Desired (trimmed) output voltage [V]
Vo=1.503V, Vo=1.800V, Vo=2.505V, Vo=3.308V, Vo=5.002V, Vo=12.007V
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302  Tel [phone]  Fax [phone]  www.belfuse.com
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