8405

LOW-DROPOUT

REGULATORS

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036 (508) 853-5000

Dwg. ES-015

ENABLE

(ACTIVE HIGH)

INPUT

(7.0 V MAX)

OUTPUT (2.0 V TO 6.8 V)

0.1

µF

(MIN)

1

µF

(MIN)

R1

R2

(300 k

Ω MAX)

VR

APPLICATIONS INFORMATION

Linear regulators require input and output capacitors in order to

maintain over-all loop stability. The recommended minimum

value for the input capacitor is 0.1

µF. The output capacitor is

the dominant pole that provides the high-frequency compensa-

tion required for over-all regulator loop stability. These devices

are stable with as little as 1

µF. However, to ensure stable

operation under all conditions and capacitor types, the recom-

mended minimum value is 4.7

µF. The output capacitor may be

partially distributed through the load circuits. However, at least

1

µF should be connected at the regulator using the shortest and

widest foil pattern possible.

The A8405SLH-ADJ requires an external voltage divider to set

up the desired regulated output voltage between 2.0 V and 6.8 V

≤ 7 V). The two resistors are chosen such that

The resistor values are usually as high as possible to maintain

Ω.

Thermal Considerations

These devices are intended to provide more than 150 mA of

continuous current in a very small package. The table on page 2

of this data sheet gives the maximum allowable average output

with a minimum footprint). Performance improvement is easily

accomplished with the addition of 1 square inch of copper at