Pin description

AN1723

4/24

Doc ID 9553 Rev 4

1

Pin description

Table 1.

Pin functions

N.

Name

Description

1

OUT

Regulator output

2

SYNC

Master/slave synchronization. When open, a signal synchronous with the turn-off of internal power is

present at the pin. When connected to an external signal at a frequency higher than the internal signal,

the device is synchronized by the external signal.

When connecting the SYNC pins of two devices together, the one with the higher frequency works as

master and the other as slave.

3INH

A logical signal (active high) disables the device. With IHN higher than 2.2 V the device is OFF and

with INH lower than 0.8 V, the device is ON.

If INH is not used, the pin must be grounded. When it is open, an internal pull-up disables the device.

4

COMP E/A output to be used for frequency compensation.

5FB

Step-down feedback input. Connecting the output voltage directly to this pin results in an output

voltage of 1.235 V. An external resistor divider is required for higher output voltages (the typical value

for the resistor connected between this pin and ground is 4.7 k

Ω).

Reference voltage of 3.3 V. No filter capacitor is needed for stability.

7

GND

Ground

Unregulated DC input voltage.

Figure 2.

Package

Figure 3.

Pin connection

AM11311v1

HSOP8-exposed pad

OUT

SYNC

INH

COMP

1

3

2

4

VCC

VREF

GND

FB

8

7

6

5

D98IN955

AM11310v1