IRF IRAUDAMP6, User Manual, Page: 3 / 47

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IRAUDAMP6 REV 1
.0
Introduction
The IRAUDAMP6 reference design is a two-channel, 250W/ch (8Ω) load half-bridge Class D audio power
amplifier. This reference design demonstrates how to use the IRS20957S Class D audio controller and gate
driver IC, implement protection circuits, and design an optimum PCB layout using the IRF6785 DirectFET
MOSFETs. This reference design does not require increasing the size of the heatsink or require fan cooling
for normal operation (one-eighth of continuous rated power).The reference design provides all the required
housekeeping power supplies for ease of use. The two-channel design is scalable for power and the number
of channels.
Applications
•
AV receivers
•
Home theater systems
•
Mini component stereos
•
Powered speakers
• Sub-woofers
•
Musical Instrument amplifiers
Features
Output Power: 250W x 2 channels (8Ω load),
Residual Noise: 90
µ
V, IHF-A weighted, AES-17 filter
Distortion: 0.005% THD+N @ 125W, 8Ω
Efficiency: 96% @ 250W, 8Ω, single-channel driven, Class D stage
Multiple Protection Features: Over-current protection (OCP), high side and low side
Over-voltage protection (OVP),
Under-voltage protection (UVP), high side and low side
DC-protection (DCP),
Over-temperature protection (OTP)
PWM Modulator: Self-oscillating half-bridge topology with optional clock synchronization
Specifications
General Test Conditions (unless otherwise noted) Notes / Conditions
Supply Voltages ±73.5V
Load Impedance 8-4Ω
Self-Oscillating Frequency 400kHz No input signal, Adjustable
Gain Setting 33dB 1Vrms input yields rated power
Electrical Data Typical Notes / Conditions
IR Devices Used IRS20957S Audio Controller and Gate-Driver,
IRF6785 DirectFET MOSFETs
Modulator Self-oscillating, second order sigma-delta modulation, analog input
Power Supply Range ± 38V to ±75V Bipolar power supply
Output Power CH1-2: (1% THD+N) 320W 1kHz
Output Power CH1-2: (10% THD+N) 410W 1kHz