Pin connections and functions

L6731B

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Pin connections and functions

Figure 2.

Pins connection ( Top view)

Table 3.

Pin functions

Pin n.

Name

Function

1

PGOOD

This pin is an open collector output and it is pulled low if the output voltage is not

within the specified thresholds (90%-110%). If not used it may be left floating. Pull-up

2

This pin is connected to the output of an internal buffer that provides ½ of DDR-IN.

with 10nF capacitor.

3

SGND

All the internal references are referred to this pin.

4

FB

the compensation network. This pin is also used to sense the output voltage in order

to manage the over voltage conditions and the PGood signal.

5

COMP

This pin is connected to the error amplifier output and is used to compensate the

voltage control feedback loop.

6

SS/INH

The soft-start time is programmed connecting an external capacitor from this pin and

GND. The internal current generator forces a current of 10

µA through the capacitor.

When the voltage at this pin is lower than 0.5V the device is disabled.

7

DDR-IN

By setting the voltage at this pin is possible to select the internal/external reference

and the switching frequency:

1

2

3

4

5

6

11

12

HTSSOP16

13

14

15

16

SGND

DDR-IN

FB

PGOOD

VTTREF

COMP

VCC

LGATE

PHASE

SS/INH

PGND

7

10

VCCDR

BOOT

HGATE

8

9

OCL

OCH