Table 1. Pins description

N°

PowerSSO-12

pin name

Function

1

VS

Supply voltage.

Block directly to ground with ceramic capacitor ≥ 4.7 µF and a

100 nF capacitator as close as possible to the pin.

2

SEL1

Output voltage selectors.

3

SEL2

4

SEL3

5

TW

Advanced Thermal warning output.

If the device detects a junction temperature above the warning

threshold, the pin is pulled low. If an overvoltage condition

occurs, a square wave is provided through the TW output. Leave

floating if not used.

6

IShort

Programmable short circuit output current input pin. A resistor

between Ishort pin and GND sets the short circuit output current

value.

7

EN

Enable input.

With the Enable high, regulator, watchdog and reset are

operating. With the Enable low, regulator, watchdog and reset

are shutdown, while the fast discharge circuit is turned on.

Connect the Enable to Vs to keep the device always enabled

8

GND

Ground reference.

9

Vcw

Watchdog timer adjust.

A capacitor between Vcw pin and GND sets the time response of

the watchdog monitor.

10

Wi

Watchdog refresh input.

If the square wave frequency at this input pin is too low, a low

pulse at RST pin is generated.

11

RST

Reset output.

It is pulled down when output voltage goes below VO_th or

frequency at Wi is too low. Leave floating if not used.

12

VO

Voltage regulator output.

Block to ground with a capacitor ≥ 3.3 µF (needed for regulator

stability).

TAB

Connected to ground

L99VR02J

Block diagram and pin descriptions

DB3869 - Rev 2

page 3/7