12W+12W, Low-EMI, Spread-Spectrum,

Stereo, Class D Amplifier

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7

Detailed Description

The MAX9741 low-EMI, Class D audio power amplifier

features several improvements to switch-mode amplifi-

er technology. This device offers Class AB perfor-

mance with Class D efficiency, while occupying

minimal board space. A unique modulation scheme

and spread-spectrum switching mode create a com-

pact, flexible, low-noise, efficient audio power amplifier.

The differential input architecture reduces common-

mode noise pickup, and can be used without input-

coupling capacitors. The device can also be

configured as a single-ended input amplifier.

PIN

NAME

FUNCTION

1, 4, 7, 11–15, 19, 21,

23, 25, 28, 33–36, 39,

42, 43, 44, 49, 50, 55, 56

N.C.

No Connection. Not internally connected.

2, 3, 40, 41

PGND

Power Ground

5, 6, 37, 38

VDD

Power-Supply Input

8

C1N

Charge-Pump Flying Capacitor Negative Terminal

9

C1P

Charge-Pump Flying Capacitor Positive Terminal

10

CHOLD

Charge-Pump Hold Capacitor. Connect a 1µF capacitor from CHOLD to VDD.

16

INL-

Left-Channel Negative Input

17

INL+

Left-Channel Positive Input

18

SHDN

Active-Low Shutdown. Connect SHDN to GND to disable the device. Connect to VDD for

normal operation.

20

SS

Soft-Start. Connect a 0.47µF capacitor from SS to GND to enable soft-start feature.

22

AGND

Analog Ground

24

REG

Internal Regulator Output. Bypass with a 0.01µF capacitor to PGND.

26

INR-

Right-Channel Negative Input

27

INR+

Right-Channel Positive Input

29

G1

Gain-Select Input 1

30

G2

Gain-Select Input 2

31

FS1

Frequency-Select Input 1

32

FS2

Frequency-Select Input 2

45, 46

OUTR-

Right-Channel Negative Audio Output

47, 48

OUTR+

Right-Channel Positive Audio Output

51, 52

OUTL-

Left-Channel Negative Audio Output

53, 54

OUTL+

Left-Channel Positive Audio Output

—EP

Exposed Paddle. Connect to GND.

Pin Description