MAX9701 MAXIM [Maxim Integrated Products], MAX9701 Datasheet - Page 10

• Manufacturer Part Number: MAX9701
• Description: 1.3W, Filterless, Stereo Class D Audio Power Amplifier
• Manufacturer: MAXIM [Maxim Integrated Products]

The MAX9701 filterless, stereo class D audio power
amplifier features several improvements to switch-mode
amplifier technology. The MAX9701 offers class AB per-
formance with class D efficiency, while occupying mini-
mal board space. A unique, filterless modulation
scheme, synchronizable switching frequency, and
spread-spectrum switching mode create a compact,
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 inputs can also be configured to accept
a single-ended input signal.
1.3W, Filterless, Stereo Class D Audio
Power Amplifier
Figure 1. MAX9701 Outputs with an Input Signal Applied
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V
V
V
IN+
OUT+
IN-
- V
OUT-
OUT+
OUT-
Detailed Description
t
ON(MIN)
t
SW
Comparators monitor the MAX9701 inputs and compare
the complementary input voltages to the sawtooth wave-
form. The comparators trip when the input magnitude of
the sawtooth exceeds their corresponding input voltage.
Both comparators reset at a fixed time after the rising
edge of the second comparator trip point, generating a
minimum-width pulse (t
ond comparator (Figure 1). As the input voltage increases
or decreases, the duration of the pulse at one output
increases while the other output pulse duration remains
the same. This causes the net voltage across the speaker
(V
helps the device to achieve high levels of linearity.
OUT+
- V
OUT-
) to change. The minimum-width pulse
ON(MIN)
) at the output of the sec-