LP2950/2951

Micrel

3-44

February 1999

OUTPUT

VOLTAGE

INPUT

VOLTAGE

ERROR

NOT

VALID

NOT

VALID

5V

1.3V

4.75V

Figure 1. ERROR Output Timing

870 23

*SEE APPLICATIONS

INFORMATION

*

*

* SEE APPLICATIONS INFORMATION

NOTE: PINS 2 AND 6 ARE LEFT OPEN

LP2951

IN

OUT

GND

FB

ERROR

5

3

4

1

8

SD

V

V

ERROR

OUTPUT

SHUTDOWN

INPUT

IN

+V

100k

Ω

OUT

V

1.2

30V

1

R

100

pF

3.3µF

2

R

1.23V

REF

V

7

OUT

V

REF

= V

x (1 +

)

1

R

2

R

OFF

ON

LP2951

Figure 2. Adjustable Regulator

Typical Applications

LP2951

OUT

FB

SO

ERROR

5

1

3

7

GND

4

+VIN

8

+VIN

*V

≈VIN

OUT

V

ERROR

OUTPUT

SHUTDOWN

INPUT

*HIGH INPUT LOWERS V

MIC2951

SD

V

ERROR

GND

4

7

8

OUT

+V IN

FB

1

5

3

ERROR

OUTPUT

SHUTDOWN

INPUT

47k

Ω

*SLEEP

INPUT

100pF

2N3906

200k

Ω

1%

100k

Ω

C-MOS

GATE

+V IN

1%

100k

Ω

+

3.3

µF

+V OUT

470 k

Ω

OFF

ON

LP2951

5 V Regulator with 2.5 V Sleep Function

Wide Input Voltage Range Current Limiter

*MINIMUM INPUT-OUTPUT VOLTAGE RANGES FROM 40mV TO 400mV,

DEPENDING ON LOAD CURRENT. CURRENT LIMIT IS TYPICALLY 160mA.