AX5688C

AX5688C

2-Channel, Digital-Input Class-D Audio Controller

Description

The AX5688C is a 2-channel bridge-tied load (BTL) audio amplifier controller IC with digital inputs and CMOS-level pulse-width modulation (PWM) outputs. The device enables high-order digital control loops with feedback for Class-D output filters.

Embedded low-latency analog-to-digital converters (ADCs) are used to close the loop behind the output filter in the digital domain. The digital control loop has a high loop gain for all audio frequencies. The AX5688C suppresses all errors caused by the power supply, power stage, and output filter within the audio band (20Hz to 20kHz). It can achieve superb performance levels while enabling lower-cost options.

The low-latency ADCs, PWM outputs, and configurable interconnects allow for custom configurations, including analog audio inputs, analog line outputs, power supply control, current-sensing, temperature-sensing, and more.

The AX5688C is compatible with power stages from various vendors, and can read and respond to power stage diagnostic signals. The maximum output power (P_OUT) is dependent on the user application and is scalable based on the number of channels, selected power stages, loads, and supply.

The AX5688C is available in a QFN-64 (9mmx9mm) package.

Features & Benefits

General Features:
- 2-Channel Bridge-Tied Load (BTL) Digital Class-D Amplifier Controller with Digital Inputs
- 4 Differential Low-Latency Analog-to-Digital Converters (ADCs) with a 115dB Dynamic Range
- 4 Configurable Digital Loop-Filter Slices
- 4 CMOS-Level Pulse-Width Modulation (PWM) Outputs
- Feedback (FB) Loop Possible after the Output Filter, across the Loudspeaker Nodes
- Configurable Interconnections Between Slices and ADCs for Versatility and Multiple-Input/Multiple-Output (MIMO) Control
- Volume Control and Soft Mute
- Dynamic Loop Control with Configurable Ramp Enabling Pop-Free Mode Transitions
Serial Audio Input/Output:
- I²S/TDM Serial Audio Interface with 16 Downstream and 8 Upstream Channels
- 32kHz to 768kHz Input Sample Rate
- 16-Bit to 32-Bit Supported Audio Formats
Control Interface:
- Serial Peripheral Interface (SPI)
- Fast-Mode I²C Control Interface with Selectable Address for Multi-Chip Systems