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POWER MANAGEMENT

SC453

Pin Configuration

Pin Descriptions

Pin#

TSSOP-28

Pin#

MLPQ-32

Pin

Name

Pin Function

1

29

DRN

This pin connects to the junction of the switching and synchronous MOSFETs.

2

30

TG

Gate drive for the switching (high-side) MOSFET.

3

31

BST

Bootstrap pin. A capacitor is connected between BST and DRN pins to develop the

floating bootstrap voltage for the high-side MOSFET gate drive.

4

1

SLP

Sleep logic input signal.

5

2

SLPV

Connect this pin to V

is selected and the voltage on this pin sets the DAC output during sleep.

6

3

BOOTV

The voltage on this pin sets the Boot-Up voltage.

7

4

PG#

Start clock indicator open drain output — Active low

8

5

HYS

Core Comparator Hysteresis — Connect to ground through an external resistor. Hys-

teresis current is established by the internal V

HYS resistance (R

9

6

VID5

VID input, most significant bit of the voltage programming DAC input

10

7

VID4

VID input

11

8

VID3

VID input

12

9

VID2

VID input

13

10

VID1

VID input

14

11

VID0

VID input, least significant bit of the voltage programming DAC input

15

12

SS

Soft-start — an external cap defines the soft-start ramp.

16

13

PG_DEL

Delayed Power Good — open drain output. After the V

the VID_DAC setting, and the t

down MOSFET opens and the pin is pulled high by an external resistor.

17

14

CORE

Feedback input for the V

high frequency noise to prevent false or faulty trip conditions.

18

15

DAC

Main controller digital-to-analog output

19

16

GND

Analog ground

20

18

REFIN

Core Comparator reference input pin — connect to DAC.

21

19

VCCA

5V supply for precision analog circuitry

22

20

CLRF

Current limit reference input

23

21

CMP

Core Comparator input

24

22

CL

Current limit input