Symbol

Parameter

Conditions

Typical

LP2956AI

LP2956I

Units

Min

Max

Min

Max

I

OH

Output “HIGH” Leakage

V

0.01

1

1

μA

V

2

2

V

OL

Output “LOW” Voltage

V

150

250

250

mV

I

400

400

I

B

Input Bias Current

0

10

−30

30

−30

30

nA

−50

50

−50

50

GROUND PIN CURRENT

I

GND

Ground Pin Current

I

170

250

250

μA

(Note 15)

I

280

280

I

1.1

2

2

I

2.5

2.5

I

3

6

6

I

8

8

I

16

28

28

mA

I

33

33

I

3

6

6

I

8

8

I

6

8

8

I

10

10

I

GND

Ground Pin Current

V

325

325

at Dropout (Note 15)

I

270

350

350

I

μA

I

GND

Ground Pin Current

No Load on Either Output

120

180

180

at Shutdown (Note 15)

I

200

200

Note 1: Absolute maximum ratings indicate limits beyond which damage to the component may occur. Electrical specifications do not apply when operating the

device outside of its rated operating conditions.

Note 2: The maximum allowable power dissipation is a function of the maximum junction temperature, T

.

Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown. See Application Hints

for additional information on heat sinking and thermal resistance.

Note 3: When used in dual-supply systems where the regulator load is returned to a negative supply, the output voltage must be diode-clamped to ground.

Note 4: May exceed the input supply voltage.

Note 5: Output or reference voltage temperature coefficient is defined as the worst case voltage change divided by the total temperature range.

Note 6: Load regulation is measured at constant junction temperature using low duty cycle pulse testing. Two separate tests are performed, one for the range of

100

μA to 1 mA and one for the 1 mA to 250 mA range. Changes in output voltage due to heating effects are covered by the thermal regulation specification.

Note 7: Dropout voltage is defined as the input to output differential at which the output voltage drops 100 mV below the value measured with a 1V differential.

At very low values of programmed output voltage, the input voltage minimum of 2V (2.3V over temperature) must be observed.

Note 8: Thermal regulation is the change in output voltage at a time T after a change in power dissipation, excluding load or line regulation effects. Specifications

are for a 200 mA load pulse at V

load pulse at V

Note 9: Connect a 0.1

μF capacitor from the output to the feedback pin.

Note 10: Load regulation is measured at constant junction temperature using low duty cycle pulse testing. Two separate tests are performed, one for the range

of 100

μA to 1 mA and one for the 1 mA to 75 mA range. Changes in output voltage due to heating effects are covered by the thermal regulation specification.

Note 11: Dropout dectection comparator thresholds are expressed as changes in a 5V output. To express the threshold voltages in terms of a differential at the

Feedback terminal, divide by the error amplifier gain = V

Note 12: The shutdown input equivalent circuit is the base of a grounded-emitter NPN transistor in series with a current-limiting resistor. Pulling the shutdown

input high turns off the main regulator. For more details, see Application Hints.

Note 13: The auxiliary regulator output has foldback limiting, which means the output current reduces with output voltage. The tested limit is for V

the output current will be higher at higher output voltages.

Note 14: This test is performed with the auxiliary comparator output sinking 400

μA of current. At the upper trip point, the comparator output must be

the low trip point, the comparator output must be

5

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11339 Version 8 Revision 4

Print Date/Time: 2009/12/07 17:53:15