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L6997S

IC Supply Voltage.

6

GND

Signal ground

7

VREF

0.6V voltage reference. Connect a ceramic capacitor (max. 10nF) between this pin and

ground. This pin is capable to source or sink up to 250uA

8

VFB

PWM comparator feedback input. Short this pin to INT pin to enable the integrator function, or

to VSENSE to disable the integrator function.

9

OSC

Connect this pin to the input voltage through a voltage divider in order to provide the feed-

forward function don’t leave floating.

10

SS

Soft Start pin. A 5

µA constant current charges an external capacitor. Itsvalue sets the soft-

start time don’t leave floating.

11

ILIM

An external resistor connected between this pin and GND sets the current limit threshold don’t

leave floating..

12

SHDN

Shutdown. When connected to GND the device and the drivers are OFF. It cannot be left

floating.

13

OVP

Open drain output. During the over voltage condition it is pulled up by an external resistor.

14

PGOOD

Open drain output. It is pulled down when the output voltage is not within the specified

thresholds. Otherwise is pulled up by external resistor. If not used it can be left floating.

15

PGND

Low Side driver ground.

16

LGATE

Low Side driver output.

17

Low Side driver supply.

18

PHASE

Return path of the High Side driver.

19

HGATE

High side driver output.

20

BOOT

Bootstrap capacitor pin. High Side driver is supplied through this pin.

Table 5. Electrical Characteristics

Symbol

Parameter

Test Condition

Min.

Typ.

Max.

Unit

SUPPLY SECTION

Vin

Input voltage range

Vout=Vref Fsw=110Khz Iout=1A

1

35

V

35.5

V

Turn-onvoltage

2.86

2.97

V

Turn-off voltage

2.75

2.9

V

Hysteresis

90

mV

Drivers Quiescent Current

VFB > VREF

7

20

µA

IqVcc

Device Quiescent current

VFB > VREF

400

600

µA

SHUTDOWN SECTION

SHDN

Device On

1.2

V

Device Off

0.6

V

Drivers shutdown current

SHDN to GND

5

µA

Devices shutdown current

SHDN to GND

1

15

µA

SOFT START SECTION

Soft Start current

4

6

µA

Active Soft start and voltage

300

400

500

mV

Table 4. Pin Function (continued)

N°

Name

Description