Summary
The AK7811 is a monaural audio amplifier with Bass Enhancement (BE) and a charge pump designed to drive a piezo-electric speaker.
AK7811 adopts the original Class-D amplifier as low power consumption, and the Charge Pump converter as less external BOM.
In addition, AK7811 employs AKM Bass Enhancement architecture, which make up for weak point of Piezo speaker, Bass and loudness.
AK7811 is available in a 16-pin WLCSP of 2.3x2.35mm body. With a piezo speaker, it is ideal for portable audio applications requiring serious saving of part space and a razor-thin body.

Features

1. Monaural Class-P Amplifier
   - Piezo-Electric (Ceramic) speaker or some capacitive load driver
   - 14Vpp BTL output with built-in power booster (VDD=3.6V)
   - Low consumption driver, AKM Class-P, specialized for capacitive load
   - Filter-free for output stage
   - Supply current with no-input: 5mA
   - Shutdown current: 0.1uA
   - Selectable Gain: -25dB to +48dB
   - Short-circuit and thermal protection
2. Boost Charge pump
   - Boost to Double voltage from supply voltage
   - Original Booster allowing small external parts
3. Bass Enhancement function
   - 3 selectable sound effects (BE, LOUD, THRU)
   - 4 selectable BE frequency for different speaker characteristics (when BE ON)
   - Tunable sound quality in balance among Bass Enhanced, Sound Volume, and Treble Boost by I²C interface
   - BE function ON/OFF, and Two BE level selectable by pin-setting
4. Input Amplifier
   - Analogue signal input for differential or single-ended
   - Pop noise suppressor
5. Control registers
   - Accessible by I²C interface or Pin-setting
   - Power-down, BE-mode select by pin-setting
   - Tuning gain, BE parameters by I²C interface
6. Operational voltage and temperature
   - Power supply: 2.5V to 5.25V
   - Power supply for digital interface: 1.65V to 5.25V
   - Operational temperature: -30deg to +85deg
7. Package 16-pin WLCSP (2.3mm 2.35mm )