MAX9768 Maxim Integrated Products, MAX9768 Datasheet - Page 12

• Manufacturer Part Number: MAX9768
• Description: 10W Mono Class D Speaker Amplifier
• Manufacturer: Maxim Integrated Products

www.datasheet4u.com
10W Mono Class D Speaker
Amplifier with Volume Control
The MAX9768 10W, Class D audio power amplifier with
spread-spectrum modulation provides a significant step
forward in switch-mode amplifier technology. The
MAX9768 offers Class AB performance with Class D
efficiency and a minimal board space solution. This
device features a wide supply voltage operation (4.5V to
14V), analog or digitally adjusted volume control, exter-
nally set input gain, shutdown mode, SYNC input and
output, speaker mute, and industry-leading click-and-
pop suppression.
The MAX9768 features a 64-step, dual-mode (analog or
I
analog volume control mode, voltage applied to
SDA/VOL sets the volume level. Two address inputs
12
2
C programmed) volume control and mute function. In
(SHOWN IN ANALOG VOLUME CONTOL MODE, A
______________________________________________________________________________________
0.47µF
V
C
DD
IN
Detailed Description
20kΩ
R
IN
V
= 23.5dB, f
30kΩ
SDA/VOL
R
F
ADDR1
ADDR2
MUTE
SHDN
SYNC
SCLK
1µF
FB
IN
-3dB
Functional Diagram/Typical Application Circuit
7
8
20
19
6
5
24
23
12
= 17Hz, SPREAD-SPECTRUM MODULATION MODE, FILTERLESS MODULATION MODE, MUTE OFF)
2.7V to 3.6V
14
SHUTDOWN
CONTROL
CONTROL
MAX9768
ANALOG
V
MUTE
DD
I
2
C
9, 11
CONTROL
VOLUME
OSCILLATOR
GND
(ADDR1, ADDR2) set the volume control function
between analog and I
I
allowing for multiple devices on a single bus.
Spread-spectrum modulation and synchronizable
switching frequency significantly reduce EMI emis-
sions. The outputs use Maxim’s low-EMI modulation
scheme with minimum pulse outputs when the audio
inputs are at the zero crossing. As the input voltage
increases or decreases, the duration of the pulse at
one output increases while the other output pulse dura-
tion remains the same. This causes the net voltage
across the speaker (V
minimum-width pulse topology reduces EMI and
increases efficiency.
2
C mode there are three selectable slave addresses
BIAS
PV
21, 22
4.5V to 14V
DD
PGND
3, 16
17, 18
1, 2
15
10
13
4
1µF
BOOT+
OUT+
OUT-
BOOT-
BIAS
SYNCOUT
2
C and set the slave address. In
OUT+
C
2.2µF
BIAS
C1
0.1µF
C2
0.1µF
- V
OUT-
) to change. The