LP2950/2951

Micrel

3-46

February 1999

LP2951

SD

V

ERROR

GND

4

1

8

OUT

+V IN

FB

5

3

470k

470k

+VIN

RESET

R1

R 2

7

VOUT

+

1µF

LP2951

SD

V

ERROR

GND

4

1

8

OUT

+VIN

FB

6

5

3

TAP

SENSE

2

+

1

µF

+VOUT = 5V

+

–

C1

100k

Ω

<5.8V**

+

–

C2

100k

Ω

<6.0V**

+

–

C3

100k

Ω

<6.2V**

39k

Ω

100

k

Ω

1%

1

k

Ω

1%

1

k

Ω

1%

1%

10k

Ω

20k

Ω

R3

+

–

C4

RESET

39k

Ω

6V

LEAD-

ACID

BATTERY

+

C1-C4

LP339

7

Latch Off When Error Flag Occurs

Open Circuit Detector for 4mA to 20mA Current Loop

Regulator with State-of-Charge Indicator

*OPTIONAL LATCH OFF WHEN DROP OUT OCCURS. ADJUST R3 FOR C2

SWITCHING WHEN V

IN

IS 6.0V

**OUTPUTS GO LOW WHEN V

IN

DROPS BELOW DESIGNATED THRESHOLDS.

MIC2951

V

GND

4

1

8

OUT

VIN

FB

7

0.1µF

1N

4001

4

20mA

OUTPUT*

4.7mA

+5V

1

5

4

2

MIN. VOLTAGE

4V

360

1N457

* HIGH FOR

I < 3.5mA

L