SLIN-20E1A_10 Datasheet, PDF (14/26 Pages) Bel Fuse Inc. – NON-ISOLATED DC/DC CONVERTERS

NON-ISOLATED DC/DC CONVERTERS
4.5 Vdc - 14 Vdc Input, 0.69 Vdc - 5.5 Vdc /20 A Outputs
December 10, 2010
Bel Power, Inc. , a subsidiary of Bel Fuse, Inc.
Remote On/Off
Parameter
Signal Low (Unit On)
Signal High (Unit Off)
Active Low
Signal Low (Unit Off)
Signal High (Unit On)
Active High
Min
0
2.0
-
Vin-1
Typ
Max Unit
Notes
-
1
V
The remote on/off pin open, Unit on.
-
Vin,max V
-
3.5
V
The remote on/off pin open, Unit on.
-
Vin,max V
The SLIN-20E1Ax 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 below. When the external
transistor Q1 is in the OFF state, the internal PWM Enable signal is pulled high through an internal 24.9kΩ
resistor and the external pullup resistor and the module is ON. When transistor Q1 is turned ON, the On/Off pin is
pulled low and the module is OFF. A suggested value for R_pullup is 20kΩ.
VIN+
MODULE
Rpullup
I _ON/OFF
ON/OFF
22K
Q2
23K
+
V_ON/OFF
Q1
22K
22K
24.9K
PWM Enable
Q3
12.1K
GND _
Circuit configuration for using positive On/Off logic
For negative logic On/Off modules, the circuit configuration is shown below. The On/Off pin should be pulled high
with an external pull-up resistor (suggested value for the 4.5V to 14V input range is 20Kohms). When transistor
Q1 is in the OFF state, the On/Off pin is pulled high, internal transistor Q2 is turned ON and the module is OFF.
To turn the module ON, Q1 is turned ON pulling the On/Off pin low, turning transistor Q2 OFF resulting in the
PWM Enable pin going high and the module turning ON.
VIN+
MODULE
Rpullup1
24.9K
ON/OFF
I _ON/OFF
+
V_ON/OFF
Q1
GND
_
23K
22K
PWM Enable
Q2
12.1K
Circuit configuration for using negative On/Off logic
Bel Fuse Inc. 206 Van Vorst Street, Jersey City, NJ 07302 • Tel [phone] • Fax [phone] • www.belfuse.com
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