Bel Fuse Inc.

206 Van Vorst Street, Jersey City, NJ 07302

11

ISOLATED DC/DC CONVERTERS

24 Vdc Input

12 Vdc /20 A Output

Sep. 11, 2010

Bel Power Inc., a subsidiary of Bel Fuse Inc.

Over Current Protection

To provide protection in a fault output overload condition, the module is equipped with internal current-limiting

circuitry and can endure current limiting for a few mili-seconds. If the over current condition persists beyond a few

milliseconds, the module will shut down into hiccup mode and restart once every 800mS. The module operates

normally when the output current goes into specified range. The typical average output current is 0.02A during

hiccup.

Over Voltage Protection

The output overvoltage protection consists of circuitry that monitors the voltage on the output terminals. If the

voltage on the output terminals exceeds the over voltage protection threshold the module will shutdown into latch

off mode. The overvoltage latch can be reset by either cycling the input power or toggling the on/off signal for one

second at least.

Test setup:

Waveform:

Vin = 24 V, Load in CC Mode

CH1: Output Voltage

CH3: Output Current

Expansion of on time portion

Vo+

Vo-

Trim

R

K

CH1: Output voltage waveform

CH2: Input voltage waveform

CH3: Output Current waveform