ON/OFF, Keep-Alive and Safety

Latch-Off Control Diagrams

(Continued)

Switch ON with ON/OFF input; Keep output

biased with Keep-Alive; Hold ouput ON with

ON/OFF; Turn OFF with ON/OFF input.

(Temporary Keep-Alive Mode)

10130520

Safety Latch OFF of V

(ON/OFF going high required to turn Output back ON)

10130521

Control Logic Truth Table

ON/OFF

Input

Keep-Alive

Input

Output

Voltage

Reset

Output

Operating Condition

L

X

0V

L

Low quiescent current standby (OFF) condition

↑

X5V

Output turns ON

H

X

5V

H

Normal ON condition

↓

H

0V

L

Output turns OFF

↓

L

5V

H

Output kept ON by Keep-Alive Input

↑

L

5V

H

Output remains ON (or turns ON)

HX

∆V

OUT

≥ −300 mV

L

Output pulled out of regulation, reset flag generated

LL

V

OUT

≤ 4V

L

Output latches OFF

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