IRAUDAMP21 2x90W 2Ω Class D Audio Power Amplifier Reference Design
Reference design for a 2-channel 90W/2Ω Class D audio power amplifier using the IR4321 IC, featuring internal protection circuits and scalable power up to 135W per channel.
Overview
The IRAUDAMP21 is a reference design for a two-channel, half-bridge Class D audio power amplifier based on the IR4321 PowIRaudio integrated IC. It delivers 90W per channel into 2Ω loads using a ±18V supply without a heatsink, and up to 135W per channel with a heatsink and ±22V supply. The design utilizes a self-oscillating PWM modulator topology with optional clock synchronization and provides a fixed gain of 26dB. Integrated protection features include over-current (OCP), over-voltage (OVP), under-voltage (UVP), DC protection (DCP), and over-temperature (OTP). The document provides complete circuit specifications, performance characterization graphs, schematics, and a bill of materials.
Use Cases
- AV receivers
- Home theater systems
- Powered speakers
- Sub-woofers
- Musical instrument amplifiers
- Car audio amplifiers
- Mini component stereos
Topics
Referenced Parts
3362H-502LF
Bourns
R113 TRIMMER 5K OHM 0.5W TH
1N4148W
Diodes Incorporated
DIODE SWITCH 100V 400MW SOD123
1N4148WS
Diodes Incorporated
D1, D2 DIODE SWITCH 75V 200MW SOD323
BZT52C10
Diodes Incorporated
Z107 DIODE ZENER 10V 500MW SOD123
BZT52C15
Diodes Incorporated
Z104 DIODE ZENER 15V 500MW SOD-123
BZT52C18
Diodes Incorporated
Z106 DIODE ZENER 18V 500MW SOD-123
BZT52C8V2
Diodes Incorporated
Z108, Z109 DIODE ZENER 8.2V 500MW SOD-123
FCX491
Diodes Incorporated
Q101 TRANSISTOR NPN 60V 1A SOT-89
MMBT5401
Diodes Incorporated
Q102, Q104, Q106, Q111 TRANS PNP 150V 350MW SMD SOT23-3
MMBT5551
Diodes Incorporated
Q103, Q105, Q107, Q108, Q109, Q110, Q112 TRANS NPN 160V 350MW SMD SOT23-3
7G17A-100M-R
Inductors, Inc.
L1, L2 Class D inductor, 10uH
IR4321
Infineon
IR Devices Used IR4321 PowIRaudio integrated Class D IC
3310-IR01
Tachyonix Corporation
U_2 CS3310 Stand-alone Controller
CS3310
Cirrus Logic
U_? IC, DIGITAL VOLUME CONTROL, SOIC-16
SN74AHC1G04
Texas Instruments
U3, U4 IC SNGL INVERTER GATE SOT23-5
SN74HC14
Texas Instruments
U_3 IC HEX SCHMITT-TRIG INV 14-SOIC
| PVT412PBF | Infineon | P1 IC RELAY PHOTOVO 400V 140MA 6DIP |
| MA2YD2300L | Panasonic | D101, D102 DIODE SCHOTTKY 25V 1.0A MINI-2P |
| LM78M12CT | Texas Instruments | U_6 IC VOLT REG 12V 500MA TO220-3 |
| LM79M05CT | Texas Instruments | U_5 IC VOLT REG NEG 5V 500MA TO220-3 |
| MC78M05CTG | Onsemi | U_4 IC REG VOLT POS 500MA 5V TO220AB |
| MURA120T3G | Onsemi | D5, D6, D7, D8 DIODE ULTRA FAST 1A 200V SMA |
| 3362H-502LF | Bourns | R113 TRIMMER 5K OHM 0.5W TH |
| 1N4148W | Diodes Incorporated | DIODE SWITCH 100V 400MW SOD123 |
| 1N4148WS | Diodes Incorporated | D1, D2 DIODE SWITCH 75V 200MW SOD323 |
| BZT52C10 | Diodes Incorporated | Z107 DIODE ZENER 10V 500MW SOD123 |
| BZT52C15 | Diodes Incorporated | Z104 DIODE ZENER 15V 500MW SOD-123 |
| BZT52C18 | Diodes Incorporated | Z106 DIODE ZENER 18V 500MW SOD-123 |
| BZT52C8V2 | Diodes Incorporated | Z108, Z109 DIODE ZENER 8.2V 500MW SOD-123 |
| FCX491 | Diodes Incorporated | Q101 TRANSISTOR NPN 60V 1A SOT-89 |
| MMBT5401 | Diodes Incorporated | Q102, Q104, Q106, Q111 TRANS PNP 150V 350MW SMD SOT23-3 |
| MMBT5551 | Diodes Incorporated | Q103, Q105, Q107, Q108, Q109, Q110, Q112 TRANS NPN 160V 350MW SMD SOT23-3 |
| 7G17A-100M-R | Inductors, Inc. | L1, L2 Class D inductor, 10uH |
| IR4321 | Infineon | IR Devices Used IR4321 PowIRaudio integrated Class D IC |
| 3310-IR01 | Tachyonix Corporation | U_2 CS3310 Stand-alone Controller |
| CS3310 | Cirrus Logic | U_? IC, DIGITAL VOLUME CONTROL, SOIC-16 |
| SN74AHC1G04 | Texas Instruments | U3, U4 IC SNGL INVERTER GATE SOT23-5 |
| SN74HC14 | Texas Instruments | U_3 IC HEX SCHMITT-TRIG INV 14-SOIC |