Texas Instruments TAS6684-Q1 Digital-Input Class-D Audio Amplifier
Texas Instruments TAS6684-Q1 4-Channel Digital-Input Class-D Audio Amplifier supports up to 45V supply voltage. This device delivers maximum output power and high-fidelity audio in high and low-impedance loads with a combined output current of up to 13A. The device provides four channels at 118W (45V, 8Ω, 1% THD, BTL) and 218W (45V, 4Ω, 1% THD, BTL).
The TAS6684-Q1 integrates AC and DC load diagnostics to determine the status of the connected loads before enabling the output stage. The status can be monitored through each channel's output current sense and temperature during audio playback, which is available for each channel. The measurement can be reported to a host processor through TDM with minimal delay. The device monitors the output load condition while playing audio using real-time load diagnostics, which operate independently from the audio and host input.
The integrated DSP of the TAS6684-Q1 enables Class-H envelope tracking control to optimize system efficiency, eliminating the need to develop complex tracking software and making local boost voltage control possible without needing an external microcontroller. The TAS6684-Q1 device features an additional low-latency signal path for each channel, providing up to 70% faster signal processing at 48kHz. It also supports an audio signal path latency of < 100µs at a 96kHz sample rate, which enables time-sensitive Road Noise Cancellation (RNC) and Active Noise Cancellation (ANC) applications.
The Texas Instruments TAS6684-Q1 is offered in a 64-pin QFP package with the exposed thermal pad up. It is pin-to-pin compatible with the TAS6584-Q1.
Features
- AEC-Q100 qualified for automotive applications with -40°C to +125°C, TA temperature grade 1
- General operation
- 4.5V to 45V supply voltage, 50V load dump
- Support for 1.8V and 3.3V I/Os
- I2C control with eight address options
- < 2W idle power loss at 14.4V, < 8µA max V_BAT+PVDD shutdown loss
- Integrated DSP processing
- Class-H supply voltage control
- Thermal monitoring and foldback
- Clip detection, PVDD monitoring, and foldback
- Output current sensing by channel via I2S/TDM with no need for external circuitry
- Real-time load diagnostics
- Monitor output conditions while playing audio
- Open load, shorted load, short-to-power, short-to-ground detection
- DC and AC standby load diagnostics
- Audio inputs
- 2-4 channel I2S or 4-16 channel TDM input
- Input sample rates: 44.1, 48, 96, 192kHz
- Low latency < 100µs at 96k sample rate
- Audio outputs
- 4-channel bridge-tied load (BTL), configurable 2-channel parallel BTL (PBTL)
- 384kHz to 2MHz configurable output switching frequency
- Up to 13A channel output current
- 400VA peak BTL output power
- 118W (45V, 8Ω, 1% THD, BTL)
- 218W (45V, 4Ω, 1% THD, BTL)
- Audio performance
- THD+N 0.03% (8Ω, 1W, 1kHz)
- 111dB SNR
- 37µV (14.4V), 80µV (45V) output noise
- Protection
- Output short protection
- DC offset, undervoltage, and overvoltage
- Configurable overtemperature warning and individual channel shutdown
- I2C temperature and supply voltage readout
- Easily meets CISPR25-L5 EMC specification with advanced spread-spectrum
Applications
- Automotive external amplifier
- Automotive head unit
Simplifed Block Diagram
