MAX97000EWA+ MAXIM [Maxim Integrated Products], MAX97000EWA+ Datasheet - Page 18

• Manufacturer Part Number: MAX97000EWA+
• Description: Audio Subsystem with Mono Class D Speaker and Class H Headphone Amplifier
• Manufacturer: MAXIM [Maxim Integrated Products]

Audio Subsystem with Mono Class D
Speaker and Class H Headphone Amplifier
The MAX97000 audio subsystem combines a mono
speaker amplifier with a stereo headphone amplifier
and an analog DPST switch. The high-efficiency 725mW
Class D speaker amplifier operates directly from the bat-
tery and consumes no more than 1FA when in shutdown
mode. The headphone amplifier utilizes a dual-mode
charge pump and a Class H output stage to maximize
efficiency while outputting a ground-referenced signal
that does not require output coupling capacitors. The
headphone and speaker amplifiers have independent
volume control and on/off control. The four inputs are
configurable as two differential inputs or four single-
ended inputs. All control is performed using the 2-wire,
I
The speaker amplifier incorporates a distortion limiter to
automatically reduce the volume level when excessive
Figure 2. Signal Path
18
2
C interface.
BUMP
D1
D2
D3
D4
D5
E1
E2
E3
E4
E5
NAME
COM1
COM2
OUTN
OUTP
INB1
INB2
INA1
INA2
NC1
NC2
INA2
INA1
INB2
INB1
Detailed Description
Negative Speaker Output
Analog Switch 1 Input
Analog Switch 2 Input
Input B1. Left or negative input.
Input B2. Right or positive input.
Positive Speaker Output
Analog Switch 1 Output
Analog Switch 2 Output
Input A1. Left or negative input.
Input A2. Right or positive input.
-6dB TO +18dB
-6dB TO +18dB
INPUT A
INPUT B
MIXER
MUX
AND
clipping occurs. This allows high gain for low-level sig-
nals without compromising the quality of large signals.
The MAX97000 includes an internal regulator (LDOIN) to
generate VDD. The regulator allows single-supply opera-
tion directly from a Li+ battery.
The MAX97000 signal path consists of flexible inputs,
signal mixing, volume control, and output amplifiers
(Figure 2). The inputs can be configured for single-
ended or differential signals (Figure 3). The internal
preamplifiers feature programmable gain settings using
internal resistors and an external gain setting using a
trimmed internal feedback resistor. The external option
allows any desired gain to be selected. Following pream-
plification, the input signals are mixed, volume adjusted,
and routed to the headphone and speaker amplifiers
based on the desired configuration.
-30dB TO +20dB
-64dB TO +6dB
-64dB TO +6dB
FUNCTION
Pin Description (continued)
+12dB
0/3dB
0/3dB
Internal Linear Regulator
Signal Path