cui.com

date 12/12/2014

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CUI Inc

│ SERIES: PSF-75 │ DESCRIPTION: AC-DC POWER SUPPLY

BATTERY CHARGING SPECIFICATIONS

Block Diagram

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PSF-75-A & PSF-75-C

Alarm Signal for AC OK and Battery Low

Internal Circuit of AC OK and Battery Low

Function

Description

Alarm Output

AC OK

The signal is low when the power

supply turns on

Low

(0.3 V max. at 30 mA)

The signal is high when the power

supply turns off

High/open

(external voltage < 50 V)

Battery

Low

The signal is low when the voltage of

the battery is below:

12 V (PSF-75-A), 22 V (PSF-75-C)

Low

(0.3 V max. at 30 mA)

The signal is high when the voltage of

the battery is above:

12 V (PSF-75-A), 22 V (PSF-75-C)

High/open

(external voltage < 50 V)

Notes:

1. Alarm signal is sent out through “AC OK” and “Battery Low” pins.

2. An external voltage source is required for this function. The maximum applied voltage is 50 V and the maximum sink current is 30 mA.

PSF-75-A:

PSF-75-C:

Alarm Circuit for

PSF-75-A & PSF-75-C

Alarm Circuit for

PSF-75-B & PSF-75-D

For more information, please visit the product page.