L4992 Ver la hoja de datos (PDF) - STMicroelectronics

Número de pieza

componentes Descripción

Fabricante

L4992

TRIPLE OUTPUT POWER SUPPLY CONTROLLER

STMicroelectronics 

L4992

PIN FUNCTIONS

N.

Name

Description

1 H5STRAP +5.1V section bootstrap capacitor connection

2

VIN

Device supply voltage. From 5.5 to 25V

3

REG5 +5V regulator supply. Used mainly for bootstrap capacitors. It should be bypassed to ground.

4

V5SW Alternative device supply voltage. When the +5.1V section is operating, the device is no

longer powered through VIN but through this pin.

5

V5SNS This pin connects to the (-) input of the +5.1V internal current sense comparator

6

I5SNS This pin connects to the (+) input of the +5.1V internal current sense comparator

7

COMP5 Feedback input for the +5.1V section.

8

SOFT5 Soft-start input of the +5.1V section. The soft-start time is programmed by an external

capacitor connected between this pin and SGND. Approximately, 1ms/nF @ full load.

9

CRST Input used for start-up and shut-down timing. A capacitor defines a time of 2ms/nF.

10

PWROK Power-good diagnostic signal. This output is driven high when both switching sections are

enabled and running properly, after a delay defined by the CRST capacitor.

11

RUN5 Control input to enable/disable the 5.1V section. A high level (>2.4V) enables this section, a

low level (<0.8V) shuts it down

12

VREF Internal +3.39V high accuracy voltage generator. It can source 5mA to external load. Bypass

to ground with a 4.7µF capacitor to reduce noise.

13

SGND Signal ground. Reference for internal logic circuitry. It must be routed separately from high

current returns.

14

NOSKIP Pulse skipping mode control. A high level (>2.4V) disables pulse skipping at low load current,

a low level (<0.8V) enables it.

15

OSC

Oscillator frequency control: connect to 2.5V to select 300KHz operation, to ground or to 5V

for 200KHz operation. A proper external signal can synchronize the oscillator

16

RUN3 Control input to enable/disable the +3.3V section. A high level (>2.4V) enables this section, a

low level (>0.8V) shuts it down.

17

SOFT3 Soft-start input for the 3.3V section. The soft-start time is programmed by an external

capacitor connected between this pin and GND. Approximately, 1ms/nF @full load.

18

COMP3 Feedback input for the +3.3V section

19

I3SNS This pin connects to the (+) input of the +3.3V internal current sense comparator

20

V3SNS This pin connects to the (-) input of the +3.3V internal current sense comparator

21

V13IN 12V regulator input supply voltage, included between 13 and 20V. This voltage can be

supplied by a flyback winding on +3.3V inductor

22

REG12 12V regulator output voltage. It can source up to 150mA to an external load

23

SGND To be connected to pin 13

24 H3STRAP +3.3V section bootstrap capacitor connection

25 H3GATE Gate- driver output for the +3.3V high-side N-MOS

26

H3SRC +3.3V high-side N-MOS source connection

27 R3GATE Gate- driver output for the +3.3V low- side N-MOS (synchronous rectifier).

28

PGND3 Current return for +3.3V section drivers

29

PGND5 Current return for +5.1V section drivers

30 R5GATE Gate-driver output for the +5.1V low-side N-MOS (synchronous rectifier).

31

H5SRC +5.1V high-side N-MOS source connection

32 H5GATE Gate-driver output for the +5.1V high-side N-MOS

3/26

Share Link: