13

NON-ISOLATED DC/DC CONVERTERS

2.4 Vdc - 5.5 Vdc Input, 0.6 Vdc - 3.63 Vdc /12 A Output

Jul. 17, 2015

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

Safety Considerations

For safety agency approval the power module must be installed in compliance with the spacing and separation

requirements of the end-use safety agency standards, i.e., UL 60950-1, CSA C22.2 No. 60950-1-03, and VDE

0850:2001-12 (EN60950-1) Licensed.

For the converter output to be considered meeting the requirements of safety extra-low voltage (SELV), the input

must meet SELV requirements. The power module has extra-low voltage (ELV) outputs when all inputs are ELV.

Remote On/Off

Parameter

Min

Typ

Max

Unit

Notes

Signal Low (Unit On)

Active Low

-0.2

-

Vin-1.6

V

The remote on/off pin open, Unit on.

Signal High (Unit Off)

Vin-0.8

-

Vin,max

V

Signal Low (Unit Off)

Active High

-0.2

-

0.3

V

The remote on/off pin open, Unit on.

Signal High (Unit On)

Vin-0.8

-

Vin,max

V

The SLIN-12F2Ax modules feature an On/Off pin for remote On/Off operation. Two On/Off logic options are

available. In the Positive Logic On/Off option, the module turns ON during a logic High on the On/Off pin and

turns OFF during a logic Low. With the Negative Logic On/Off option, the module turns OFF during logic High

and ON during logic Low. The On/Off signal is always referenced to ground. For either On/Off logic option,

leaving the On/Off pin disconnected will turn the module ON when input voltage is present.

For positive logic modules, the circuit configuration for using the On/Off pin is shown in Figure A below. When the

external transistor Q1 is in the OFF state, Q2 is ON, the internal PWM Enable signal is pulled low and the module

is ON. When transistor Q1 is turned ON, the On/Off pin is pulled low, Q2 is turned off and the internal PWM

Enable signal is pulled high through the 23.7K pull-up resistor and the module is OFF.

For negative logic On/Off modules, the circuit configuration is shown in Figure B below. The On/Off pin should be

pulled high with an external pull-up resistor (suggested value for the 2.4V to 5.5Vin range is 3Kohms). When

transistor Q1 is in the OFF state, the On/Off pin is pulled high and the module is OFF. The On/Off threshold for

module ON, Q1 is turned ON pulling the On/Off pin low.

Fig. A

Fig. B

23.7K

Q1

GND

PWM Enable

ON/OFF

VIN+

ON/OFF

_

+

I

V

MODULE

ON/OFF

Q2

20K

470

20K

60.4K

Q1

GND

PWM Enable

ON/OFF

VIN+

ON/OFF

_

+

V

I

MODULE

Rpullup

ON/OFF

R2

20K