2-channel 120 W class D audio amp reference design
5 September 2007
Analogue, Mixed Signal, LSI
Showcasing International Rectifier's IRS20955 200V digital audio driver IC and the IRF6645 DirectFET digital audio MOSFETs, the new IRAUDAMP4 reference design is a two-channel, 120 W half-bridge design offering 96% efficiency at 120 W and 4 Ω. The design incorporates critical protection features such as over-current protection, over-voltage protection, under-voltage protection, DC-protection, and over-temperature protection, in addition to housekeeping functions such as a ±5 V supply for analog signal processing for the preamplifier and a +12 V supply (Vcc) referenced to -B for the Class D gate driver stage. The two-channel design is scalable for power and number of channels, and requires no heatsink under normal operating conditions.
The IRS20955(S)(TR)PbF audio driver IC, on which the reference design is based, features a floating PWM input designed specifically for Class D audio amplifier applications. Bidirectional current sensing detects over-current conditions during positive and negative load currents without any external shunt resistors. A built-in protection control block provides a secure protection sequence against over-current conditions and a programmable reset timer. The internal dead-time generation block enables accurate gate switching and optimum dead-time setting for better audio performance, such as lower total harmonic distortion and lower audio noise floor.
The featured companion IRF6645 power MOSFETs are part of International Rectifier's DirectFET family. The innovative DirectFET packaging technology enhances performance in Class D audio amplifier circuits by reducing lead inductance to improve switching performance and reduce EMI noise. The higher thermal efficiency enables 120 W operation into 4 Ω, eliminating the need for a heatsink, thereby shrinking circuit size, providing greater layout flexibility and reducing overall amplifier system cost.
Further reading:
High-speed PIN diode
Altron Arrow
Analogue, Mixed Signal, LSI
Vishay’s new high-speed Silicon PIN diode is able to detect both visible and near infra-red radiation over a wide spectrum range from 350 to 1100 nm.
Read more...
Analogue front end for sensor measurements
Electrocomp
Analogue, Mixed Signal, LSI
The NJU9103 AFE from Nisshinbo is a tiny analogue front end, with a 16-bit resolution ADC and up to 512 x signal amplification from the programmable gain amplifier.
Read more...
Single-channel software configurable I/O
Altron Arrow
Analogue, Mixed Signal, LSI
These use cases of the AD74115H include analogue output and input, digital output and input, resistance temperature detector (RTD), and thermocouple measurement capability.
Read more...
Current-sense amplifier with PWM rejection
Altron Arrow
Analogue, Mixed Signal, LSI
Analog Devices’ AD8410A is a high voltage, high bandwidth current-sense amplifier that features an initial gain of 20 V/V and a 2,2 MHz bandwidth.
Read more...
Combining a LPF and ADC driver for a 20 Vp-p signal
Altron Arrow
Analogue, Mixed Signal, LSI
A mixed-signal ADC driver circuit’s optimum performance depends on multiple variables: the driver’s settling time, the RC filter’s time constant, driving impedance, and the ADC sampling capacitor’s kickback current, all interact during acquisition time and contribute towards sampling errors.
Read more...
Pressure sensor with NextNav certification
EBV Electrolink
Analogue, Mixed Signal, LSI
STMicroelectronics’ LPS22DF pressure sensor has received a NextNav certification, which guarantees performance and reliability for geolocation and other types of applications.
Read more...
Reference design for Raspberry Pi analogue I/O
Analogue, Mixed Signal, LSI
Analogue Devices has published a reference design for ±10 V analogue input and ±15 V analogue output for Raspberry Pi platforms.
Read more...
Multi-zone distance sensor with 90° field of view
Avnet Silica
Analogue, Mixed Signal, LSI
STMicroelectronics has revealed a new FlightSense multi-zone distance sensor, with 90° field of view, to bring lifelike situational awareness to applications like home automation, computers, robots, and smart equipment.
Read more...
Six-axis IMU with Qvar sensing channel
Altron Arrow
Analogue, Mixed Signal, LSI
The LSM6DSV16X from STMicroelectronics is a high-performance, low-power six-axis IMU, featuring a three-axis digital accelerometer and a three-axis digital gyroscope.
Read more...
Bidirectional current-sense amplifier with PWM
RS South Africa
Analogue, Mixed Signal, LSI
The MAX49925 from Analogue Devices is a bidirectional current-sense amplifier (CSA) with an input common-mode range that extends from -40 to 76 V, making it suitable for 48 V HEV applications where there are large automotive transients.
Read more...
printer friendly version