STMicroelectronics HFA80A Class-D BTL Audio Amplifier
STMicroelectronics HFA80A Class-D BTL Audio Amplifier is a quad-channel, analog input audio amplifier with advanced diagnostics, high PWM switching frequency, and high-resolution audio. The high integration level and embedded signal processing allow excellent audio performance. The HFA80A includes an I2C-bus interface to control the operation and read the state of the power amplifier, perform diagnostics, and generally access the features of this amplifier.
A dedicated clipping detector and diagnostics output pin, CD/DIAG, eases the communication load on the microcontroller and can trigger the host to read important information as it becomes available. According to programmable configuration registers, all helpful information derived from internal detectors (thermal warnings, output offset, overcurrent protection, etc.) can be selectively set to toggle the CD/DIAG pin.
The STMicroelectronics HFA80A implements a load diagnostics concept specifically designed for automotive applications. It embeds a highly reliable noise-immune load diagnostic algorithm with self-generated stimuli. This feature detects anomalous load connections or variations and makes this information available through the I2C Bus.
Features
- AEC-Q100 qualified
- 4.5V to 18V supply operating range
- EMI compliant to CISPR25 level V
- Class-D BTL outputs
- Battery load dump compatible (40V)
- Reduced size and cost of output LC thanks to 2MHz switching PWM
- Extended audio band support
- Multiple load configurations
- Able to drive 4Ω and 2Ω speaker loads
- Both speaker and line driver options
- MOSFET power outputs allow high output power capability
- Typ 4 x 28.5W/4Ω at 14.4V, 1kHz, THD = 10%
- Typ 4 x 23W/4Ω at 14.4V, 1kHz, THD = 1%
- Typ 4 x 49W/2Ω at 14.4V, 1kHz, THD = 10%
- Typ 4 x 39W/2Ω at 14.4V, 1kHz, THD = 1%
- Audio performances at 4Ω, 14.4V, 1kHz
- THD 0.015% typ at 1W, 1kHz on 4Ω loads
- Output noise 52μV (typ) at 26dB gain
- Crosstalk 86dB typ at 1W, 1kHz on 4Ω loads
- PSRR 80dB typ at 1W, 1kHz on 4Ω loads
- Fast turn-on and very low latency for high-speed audio processing applications
- Four I2C addresses
- I2C full configurability with channel-independent mute/play/gain selection/diagnostic
- I2C bus driving (fast I2C (1Mhz clock) option)
- Output PWM clock spread spectrum
- Full diagnostic matrix with info available both on I2C and CD/DIAG pin
- Independent by-channel DC and AC load detection diagnostic with selectable threshold
- Startup diagnostic for shorts to VCC/GND
- Overcurrent protection with a configurable threshold (2 selectable)
- Input voltage DC offset detector
- Free-running output current offset detector
- Thermal protection and thermal warning (four thermal warnings)
- DAM (digital admittance meter)
- Synchronization input/output pin
- Immune to pop/tick noise at turn on/off, battery variations, during diagnostic
- Legacy (backup mode without I2C control)
- ESD integrated protections (2kV HBM, 500V/750V corner CDM)
- LQFP48L exposed pad-up package
Block Diagram
