max9723aebe Maxim Integrated Products, Inc., max9723aebe Datasheet - Page 9

• Manufacturer Part Number: max9723aebe
• Description: Max9723 Stereo Directdrive Headphone Amplifier With Bassmax, Volume Control, And I?c
• Manufacturer: Maxim Integrated Products, Inc.

The MAX9723 stereo headphone amplifier features
Maxim’s patented DirectDrive architecture, eliminating
the large output-coupling capacitors required by con-
ventional single-supply headphone amplifiers. The
MAX9723 consists of two 62mW Class AB headphone
amplifiers, hardware/software shutdown control, inverting
charge pump, integrated 32-level volume control,
BassMax circuitry, comprehensive click-and-pop sup-
pression circuitry, and an I
the Functional Diagram/Typical Operating Circuit). A
negative power supply (PV
inverting the positive supply (V
fiers from V
the amplifiers to almost twice that of other single-supply
amplifiers, increasing the total available output power.
THIN QFN
PIN
EP
10
11
12
13
14
15
16
1
2
3
4
5
6
7
8
9
DD
and PV
BUMP
UCSP
_______________________________________________________________________________________
Stereo DirectDrive Headphone Amplifier
D1
C1
C4
D4
C3
D3
D2
C2
B1
A1
B2
A2
A3
B3
A4
B4
—
with BassMax, Volume Control, and I
SS
Detailed Description
increases the dynamic range of
2
C-compatible interface (see
SS
) is created internally by
NAME
PGND
SHDN
SGND
OUTR
OUTL
DD
PV
SV
C1P
C1N
SCL
SDA
BBR
BBL
V
INR
INL
EP
DD
SS
SS
). Powering the ampli-
Power-Supply Input. Bypass V
Charge-Pump Flying Capacitor Positive Terminal
Power Ground. Connect to SGND.
Charge-Pump Flying Capacitor Negative Terminal
Serial Clock Input. Connect a 10kΩ pullup resistor from SCL to V
Charge-Pump Output. Connect to SV
to PGND.
Serial-Data Input. Connect a 10kΩ pullup resistor from SDA to V
Shutdown. Drive SHDN low to disable the MAX9723. Connect SHDN to V
is high for normal operation (see the Command Register section).
Signal Ground. Connect to PGND.
Left-Channel Input
Right-Channel Input
Headphone Amplifier Negative Power-Supply Input. Connect to PV
Right BassMax Input. Connect an external lowpass filter between OUTR and BBR to
apply bass boost to the right-channel output. Connect BBR to SGND if BassMax is not
used (see the BassMax (Bass Boost) section).
Right Headphone Output
Left Headphone Output
Left BassMax Input. Connect an external lowpass filter between OUTL and BBL to
apply bass boost to the right-channel output. Connect BBL to SGND if BassMax is not
used (see the BassMax (Bass Boost) section).
Exposed Paddle. Connect EP to SV
The MAX9723 DirectDrive outputs are biased at SGND
(see Figure 1). The benefit of this 0V bias is that the
amplifier outputs do not have a DC component, elimi-
nating the need for large DC-blocking capacitors.
Eliminating the DC-blocking capacitors on the output
saves board space, system cost, and improves low-fre-
quency response.
An I
tion between the MAX9723 and a microcontroller. The
MAX9723 is available with two different I
allowing two MAX9723 ICs to share the same bus (see
Table 1). The internal command register controls the
shutdown status of the MAX9723, enables the BassMax
circuitry, sets the maximum gain of the amplifier, and
sets the volume level (see Table 2). The MAX9723’s
BassMax circuitry improves audio reproduction by
boosting the bass response of the amplifier, compen-
sating for any low-frequency attenuation introduced by
2
C-compatible interface allows serial communica-
DD
to PGND with a 1µF capacitor.
SS
SS
FUNCTION
or leave unconnected.
. Bypass PV
SS
with a 1µF capacitor
Pin Description
DD
DD
.
SS
.
.
2
DD
C addresses
while bit 7
2
C
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