10001706

*Capacitance value shown is minimum required to assure stability, but may be increased without limit. Larger output capacitor provides improved dynamic

response.

**Shutdown must be actively terminated (see Application Hints). Tie to INPUT (pin 4) if not used.

Application Hints

LLP Package Devices

The LP2987/LP2988 is offered in the 8 lead LLP surface

mount package to allow for increased power dissipation

compared to the SO-8 and Mini SO-8. For details on thermal

performance as well as mounting and soldering specifica-

tions, refer to Application Note AN-1187.

EXTERNAL CAPACITORS

As with any low-dropout regulator, external capacitors are

required to assure stability. These capacitors must be cor-

rectly selected for proper performance.

INPUT CAPACITOR: An input capacitor (

≥ 2.2 µF) is re-

quired between the LP2987/8 input and ground (amount of

capacitance may be increased without limit).

This capacitor must be located a distance of not more than

0.5” from the input pin and returned to a clean analog

ground. Any good quality ceramic or tantalum may be used

for this capacitor.

OUTPUT CAPACITOR: The output capacitor must meet the

requirement for minimum amount of capacitance and also

have an appropriate E.S.R. (equivalent series resistance)

value.

Curves are provided which show the allowable ESR range

as a function of load current for 3V and 5V outputs.

ESR Curves For 5V Output

10001707

ESR Curves For 3V Output

10001708

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