LM4651 Pin Descriptions

Pin No.

Symbol

Description

1

OUT

1

The reference pin of the power MOSFET output to the gate drive circuitry.

2,27

BS

The bootstrap pin provides extra bias to drive the upper gates, HG

3HG

1

High−Gate #1 is the gate drive to a top side MOSFET in the H-Bridge.

4HG

2

High−Gate #2 is the gate drive to a top side MOSFET in the H-Bridge.

5,15

GND

The ground pin for all analog circuitry.

6

+6V

BYP

The internally regulated positive voltage output for analog circuitry. This pin is available

for internal regulator bypassing only.

7+V

CC

The positive supply input for the IC.

8

−6V

BYP

The internally regulated negative voltage output for analog circuitry. This pin is available

for internal regulator bypassing only.

9F

The feedback instrumentation amplifier output pin.

10

E

The error amplifier inverting input pin. The input audio signal and the feedback signal are

summed at this input pin.

11

E

The error amplifier output pin.

12

TSD

The thermal shut down input pin for the thermal shut down output of the LM4652.

13

STBY

Standby function input pin. This pin is CMOS compatible.

14

FBK

1

The feedback instrumentation amplifier pin. This must be connected to the feedback filter

from V

16

OSC

The switching frequency oscillation pin. Adjusting the resistor from 15.5k

Ω to 0Ω

changes the switching frequency from 75kHz to 225kHz.

17

Delay

The dead time setting pin.

18

SCKT

Short circuit setting pin. Minimum setting is 10A.

19

FBK

2

The feedback instrumentation amplifier pin. This must be connected to the feedback filter

from V

20,21

−V

DDBYP

The regulator output for digital blocks. This pin is for bypassing only.

22,23

−V

EE

The negative voltage supply pin for the IC.

24

START

The start up capacitor input pin. This capacitor adjusts the start up time of the diagnostic

sequence for the modulator. Refer to Start up Sequence and Timing in the

Application Information section.

25

LG

1

Low−Gate #1 is the gate drive to a bottom side MOSFET in the H-Bridge.

26

LG

2

Low−Gate #2 is the gate drive to a bottom side MOSFET in the H-Bridge.

28

OUT

2

The reference pin of the power MOSFET output to the gate drive circuitry.

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