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IRAUDAMP19 REV 3.0
IRAUDAMP19
100W/4Ω x 2 Channel Class D Audio Power Amplifier
Using the IR4301
By
Jun Honda, Liwei Zheng
CAUTION:
International Rectifier suggests the following guidelines for safe operation and
handling of IRAUDAMP19 Demo board;
Always wear safety glasses whenever operating Demo Board
Avoid physical contact with exposed metal surfaces when operating Demo
Board
Turn off Demo Board when placing or removing measurement probes
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IRAUDAMP19 REV 3.0
TABLE OF CONTENTS ........................... PAGE
INTRODUCTION .............................................................................. 3
SPECIFICATIONS ........................................................................... 3
CONNECTION SETUP .................................................................... 4
TEST PROCEDURES ...................................................................... 5
PERFORMANCE AND TEST GRAPHS .......................................... 5
THERMAL INFORMATION .............................................................. 8
SCHEMATIC .................................................................................... 9
BILL OF MATERIALS .................................................................... 10
PCB SPECIFICATIONS ................................................................. 12
REVISION CHANGES DESCRIPTIONS ....................................... 14
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IRAUDAMP19 REV 3.0
Introduction
The IRAUDAMP19 reference design is a two-channel, 100W/ch (4 Ω/52V Bus voltage) half-bridge
Class D audio power amplifier with single power supply. This reference design demonstrates how to
use the IR4301 IC with single power supply, implement protection circuits, and design an optimum
PCB layout using PowIRaudio integrated Class D IC. This reference design does not require
additional heatsink or 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
Car audio amplifiers
Features
Output Power: 100W x 2 channels (10%THD+N 4Ω load; no heatsink)
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
Over-temperature protection (OTP)
PWM Modulator: Self-oscillating half-bridge topology
Specifications
General Test Conditions (unless otherwise noted) Notes / Conditions
Supply Voltages 41V~52V Without heatsink
Load Impedance 2-4Ω Resistive load
Self-Oscillating Frequency 400kHz No input signal, Adjustable
Gain Setting 24.8dB 1Vrms input yields rated power
Electrical Data Typical Notes / Conditions
IR Devices Used IR4301 PowIRaudio integrated Class D IC
Modulator Self-oscillating, second order sigma-delta modulation, analog input
Power Supply Range 41V~52V* Single power supply;
Output Power CH1-2: (1% THD+N) 82.5W 1kHz
Output Power CH1-2: (10% THD+N) 100W 1kHz
Rated Load Impedance 2-4Ω Resistive load
Idling Supply Current 67mA No input signal
Total Idle Power Consumption 3.5W No input signal
Distortion 0.02% THD+N @ 10W, 4Ω
Residual Noise 250
V IHF-A weighted, AES-17 filter
Efficiency 90% Single-channel driven, 100W, Class D
stage
*Can be powered by 30V-41V supply with modifications of power resistors and UVP zener.(Please refer Page4)
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IRAUDAMP19 REV 3.0
Connection Setup
Fig 1 Typical Test Setup
Connector Description
Audio IN CN1 Analog input for CH1 and CH2
POWER P2 Single supply
CH1 OUT P1 Output for CH1
CH2 OUT P3 Output for CH2
*IRAUDAMP19 can be powered by 30V-41V supply with modifications of power resistors and UVP zener as below.
Power supply voltage 41-52V 30-41V
R25~R28,R56,R57,R
64,R65 560 ohm 390 ohm
Z5 36V 27V
250W, Non-inductive Resistors
CN1
P1 P3
P2
CH1
Output CH2
Output
Audio
Input
41-52V*, 3A DC supply
4 Ohm 4 Ohm
Audio Signal Generator
IR4301
SW1
SW1:PWM Shutdown/MUTE
Power
Indicator
FAULT
Indicator
FAULT
Indicator
IR4301
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IRAUDAMP19 REV 3.0
Test Procedures
Test Setup:
1. Connect 4, 250W load to both output connectors, P1 and P3 and audio analyzer (Ap).
2. Connect Audio Signal Generator to CN1 for CH1 and CH2 respectively (Ap).
3. Connect a single power supply to P2 pre-adjusted to 30-52V as shown on Figure above
4. Turn on the power supply.
5. Turn on SW1 (right side).
6. Blue LED (Normal) stays turning on after RED LED extinguished.
7. With an Oscilloscope, monitor switching waveform at VS of CH1 and CH2.
8. Quiescent current for the power supply should be 55mA 10mA at 52V.
Functionality Audio Tests:
9. Sweep the audio signal voltage from 15 mVRMS to 1.5 VRMS.
10. Monitor the output signals at P1/P3 with an oscilloscope. The waveform must be a non
distorted sinusoidal signal with input sinusoidal signal below 1Vrms.
Performance and Test Graphs
Power vs THD+N (without heatsink)
Test Conditions:
VBus = 52V
Input Signal=1 kHz
Load Impedance = 4 ohms
Amp19.at27
ColorSweep Trace Line Style Thick Data Axis Comment
1 1 Red Solid 3Anlr.THD+N Ratio Left
1 3 Blue Solid 3Anlr.THD+N Ratio Left
0.001
10
0.002
0.005
0.01
0.02
0.05
0.1
0.2
0.5
1
2
5
%
70m 200100m 200m 500m 1 2 5 10 20 50 100
W
Fig 2
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IRAUDAMP19 REV 3.0
Frequency Response
Test Conditions:
VBus = 52V
Set Output = 1W
Load Impedance = 4 ohms
Amp19FR.at27
ColorSweep Trace Line Style Thick Data Axis Comment
1 1 Red Solid 3Anlr.Level A Left
1 2 Blue Solid 3Anlr.Level B Left
-10
+4
-9
-8
-7
-6
-5
-4
-3
-2
-1
-0
+1
+2
+3
d
B
r
A
20 200k50 100 200 500 1k 2k 5k 10k 20k 50k 100k
Hz
Noise Floor
Test Conditions:
VBus = 52V
Load Impedance = 4 ohms
No Input Signal
Amp19FTT,Flloor noise.at27
ColorSweep Trace Line Style Thick Data Axi s Comment
1 1 Red Solid 3Fft.Ch.1 Ampl Left
1 2 Blue Solid 3Fft.Ch.2 Ampl Left
-150
+20
-140
-130
-120
-110
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
+0
+10
d
B
V
10 20k20 50 100 200 500 1k 2k 5k 10k
Hz
Fig 3
Fig 4
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IRAUDAMP19 REV 3.0
Noise Floor with 1Vrms Output
Test Conditions:
VBus = 52V
Output = 1Vrms @ 1 KHz
Load Impedance = 4 ohms
-110
+0
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
V
10 20k20 50 100 200 500 1k 2k 5k 10k
Hz
Fig 5
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IRAUDAMP19 REV 3.0
Thermal Information:
1/8 Po Thermal Test
Conditions:
Tamb=25°C natural convection cooling
Both Channel Driven 1/8Po continuous 30mins
Temperature measured by infrared camera
Fig 6 IRAUDAMP19 (Vbus=52V)
IR4301’s temperature saturated around 80°C within 30minutes
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IRAUDAMP19 REV 3.0
Schematic
Fig7
D1
+B
GND
SD
VCC
R31
4.7R
IN+
3
GND
2
VAA
1
VB 13
VP 12
COMP
5
VN
10
VS 11
VCC
8
CSD
6
IN-
4
VSS
7
COM
9
CSH 14
O
15
U1
PQFN
C15
1nF
+5V
-5V
SD
C21
10uF
22uF
C23
Cla ss D, AM P19 Sc hematic
SCH_IR4301_Single Supply Rev2.3
C6
2.2nF,50V
C13
2.2nF,50V
C7 22uF, 16V
C17
4.7uF,10V
C19
4.7uF,10V
D3
1N4148
R29
4.7R
R20 180R
-B
R51 10k, 1/ 2WR5210k, 1/ 2W
VS1
R49 2.2k
R4710, 1W
C35
0. 47uF, 400V
+
-
LCH
CH1_OUT
Z1
5.1V
CT_PGND
CT_SGND
Z3
5.1V
CT_SGND
R3100k
R5
330 C1
1nF
R6
330 C2
1nF
R11
*3.01k 1%
R12
*3.01k 1%
CT_SGND
CT_SGND
CT_SGND
C5
2.2nF,50V
C11
2.2nF,50V
R19
180R
R23
180R
R1
10k
Prot 1
Red LED
CT_SGND
R55
10k
R53
47k
R54
10k R58
47k
R59
10k
R60
47k
12
3
54
6
S1
SW SPDT
C41
0.1uF
Q3
MMBT5551
Q4
MMBT5551
+B
SD
OVP
UVP
+B CT_PGND
+B
GND
VSS1
C29
0.1uF,100V
R41
1R
D2
+B
GND
SD
VCC
R32
4.7R
IN+
3
GND
2
VAA
1
VB 13
VP 12
COMP
5
VN
10
VS 11
VCC
8
CSD
6
IN-
4
VSS
7
COM
9
CSH 14
O
15
U2
PQFN
C16
1nF
+5V
-5V
SD
C22
10uF
22uF
C24
C9
2.2nF,50V
C14
2.2nF,50V
C10 22uF, 16V
C18
4.7uF,10V
C20
4.7uF,10V
D4
1N4148
R30
4.7R
R22 180R
-B VS2
R50 2.2k
R4810, 1W
C36
0. 47uF, 400V
RCH
CH2_OUT
CT_PGND
CT_SGND
CT_SGND
R4100k
R7
330 C3
1nF
R8
330 C4
1nF
R13
*3.01k 1%
R14
*3.01k 1%
CT_SGND
CT_SGND
CT_SGND
C8
2.2nF,50V
C12
2.2nF,50V
R21
180R
R24
180R
Prot 2
Red LED
CT_SGND
VSS2
C30
0.1uF,100V
R42
1R
3
2
1
FET2
BS250F
3
2
1
FET1
BS250F
52V version
GND
GND
C44
NM
R36
NM
2
1
3
5
4
CN1
1
23 MJD44H11T4GQ1
Z5
11V
CP5
22uF
+B
1
2
P3
+B
GND
1
2
P1
1
2
P2
C38
0. 1uF, 63V
OFF
ON
VAA2
VAA1
CT_SGND CT_PGND
I NPUT GND
INPUT GND
R61
10R
DS1
CT_PGND
CT_PGND
D9
1N4148
D10
1N4148
C45 470pF, 5 0V
GND
CP1
2.2uF
C37
0. 1uF , 63V
R63
10R
CT_PGND CT_PGND
CT_PGNDCT_PGND
Z2
5.1V
Z4
5.1V
CP2
2.2uF
CP3
2.2uF
CP4
2.2uF
R38
NM
R15 68.1 k 1%
R25
*560 1W
R10
47K
R9
47K
R2
10k
R62
10k
R39
560 1/ 2W
R35 9.1k
R40 9.1k
R33
33K
R34
33K
C31
0.1uF,100V
C32
0.1uF,100V
C42
2200uF, 63V
C39
0.1uF,100V
C40
0.1uF,100V
C43
2200uF, 63V
+30-52V
L1
22uH
L2
22uH
R16 68.1 k 1%
R17 68.1 k 1%
R18 68k 1%
D6
D5
D7
D8
Power S upply
V olt age Range
390ohm
36V
560Ohm
27V
41-52V 30-41V
R25~R28,R56
Z5
*
R57,R64,R65
Z7
56V
*
Z8
*36V
R38
R61
Single Supply
Not mounted
10 Ohm
Dual S upply
10 Ohm
Not mounted
R37
560 1/ 2W
R56
560 1/2W
R57
*560 1W
R26
560 1/ 2W
R27
*560 1W
R64
560 1/2W
R65
*560 1W
R28
560 1/ 2W
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IRAUDAMP19 REV 3.0
Bill of Materials
No Part Number Designator Description Quantity Vendor
1 490-1494-1-ND
C1, C2, C3, C4, C15,
C16
CAP CER 1000PF 50V 10%
X7R 0603 6 Digikey
2 445-1309-1-ND
C5, C6, C8, C9, C11,
C12, C13, C14
CAP CER 2200PF 50V X7R
10% 0603 8 Digikey
3 587-1433-1-ND C7, C10 CAP CER 22UF 16V X5R 1206 2 Digikey
4 478-1429-1-ND C17, C18, C19, C20 CAP CER 4.7UF 10V Y5V 0805 4 Digikey
5 399-3525-1-ND C21, C22
CAP CERAMIC 10UF 16V X7R
1206 2 Digikey
6 445-6797-1-ND C23, C24
CAP CER 22UF 16V 10% X5R
0805 2 Digikey
7 445-1418-1-ND C29, C30
CAP CER .10UF 100V X7R
10% 0805 2 Digikey
8 445-1377-1-ND C31, C32, C39, C40
CAP CER 0.1UF 100V 10%
X7R 1206 4 Digikey
9 495-1315-ND C35, C36
CAP FILM 0.47UF 400VDC
RADIAL 2 Digikey
10 BC2054-ND C37, C38
CAP FILM MKP .1UF 63VDC
2% 2 Digikey
11 311-1140-1-ND C41
CAP .10UF 50V CERAMIC X7R
0805 1 Digikey
12 565-1137-ND C42, C43
CAP ALUM 2200UF 63V 20%
RADIAL 2 Digikey
13 311-1124-1-ND C45
CAP 470PF 50V CERAMIC
X7R 0805 1 Digikey
14 CP1-3545N-ND CN1
CONN JACK STEREO R/A
5PIN 3.5MM 1 Digikey
15 565-1103-ND CP1, CP2, CP3, CP4
CAP ALUM 2.2UF 50V 20%
RADIAL 4 Digikey
16 565-1056-ND CP5
CAP 22UF 25V ELECT VR
RADIAL 1 Digikey
17 1N4148WS-FDICT-ND D1, D2
DIODE SWITCH 75V 200MW
SOD323 2 Digikey
18 1N4148WDICT-ND D3, D4, D9, D10
DIODE SWITCH 100V 400MW
SOD-123 4 Digikey
19 S1DFSCT-ND D5, D6, D7, D8 DIODE GP 200V 1A DO214AC 4 Digikey
20 160-1647-1-ND DS1
LED BLUE CLEAR THIN 0603
SMD 1 Digikey
21 BS250FCT-ND FET1, FET2
MOSFET P-CH 45V 90MA
SOT23-3 2 Digikey
22 7G14A-220M-B L1, L2 Class D Inductor, 22UH 2
Inductors,
Inc
23 281-1414-ND P1, P3
CONN TERM BLOCK PCB
5.0MM 2POS 2 Digikey
24 281-1414-ND P2
CONN TERM BLOCK PCB
5.0MM 2POS 1 Digikey
25 160-1182-1-ND Prot1, Prot2
LED RED ORANGE CLEAR
0603 SMD 2 Digikey
26 MJD44H11T4GOSCT-
ND Q1
TRANS PWR NPN 8A 80V
DPAK 1 Digikey
27 MMBT5551FSCT-ND Q3, Q4
TRANSISTOR NPN 160V SOT-
23 2 Digikey
28 311-10KGRCT-ND R1, R2, R62
RES 10K OHM 1/10W 5% 0603
SMD 3 Digikey
29 RMCF0603JT100KCT-
ND R3, R4
RES 100K OHM 1/10W 5%
0603 SMD 2 Digikey
30 RMCF0603JT330RCT-
ND R5, R6, R7, R8
RES 330 OHM 1/10W 5% 0603
SMD 4 Digikey
31 RHM47KGCT-ND R9, R10
RES 47K OHM 1/10W 5% 0603
SMD 2 Digikey
32 RHM3.01KCRCT-ND R11, R12, R13, R14
RES 3.01K OHM 1/8W 1% 0805
SMD 4 Digikey
33 RMCF0805FT68K1CT-
ND R15, R16, R17, R18
RES 68.1K OHM 1/8W 1% 0805
SMD 4 Digikey
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IRAUDAMP19 REV 3.0
34 RHM180GCT-ND
R19, R20, R21, R22,
R23, R24
RES 180 OHM 1/10W 5% 0603
SMD 6 Digikey
35 RHM560BCCT-ND R25, R27, R57, R65
RES 560 OHM 1W 5% 2512
SMD 4 Digikey
36 560H-ND
R26, R28, R37, R39,
R56, R64 RES 560 OHM 1/2W 5% AXIAL 6 Digikey
37 P4.7ACT-ND R29, R30, R31, R32
RESISTOR 4.7 OHM 1/8W 5%
0805 4 Digikey
38 RHM33KGCT-ND R33, R34
RES 33K OHM 1/10W 5% 0603
SMD 2 Digikey
39 RHM9.1KARCT-ND R35, R40
RES 9.1K OHM 1/8W 5% 0805
SMD 2 Digikey
40 1.1KW-1-ND R37
RES 1.1K OHM 1W 5% METAL
OXIDE 2 Digikey
41 923345-06-ND JW1
JUMPER WIRE 0.6" LONG
PKG OF 150 1 Digikey
42 P1.0ACT-ND R41, R42
RESISTOR 1.0 OHM 1/8W 5%
0805 2 Digikey
43 541-10.0AFCT-ND R47, R48
RES 10.0 OHM 1W 1% 2512
SMD 2 Digikey
44 RMCF0805JT2K20CT-
ND R49, R50
RES 2.2K OHM 1/8W 5% 0805
SMD 2 Digikey
45 541-10KVCT-ND R51, R52
RES 10K OHM 1/2W 5% 1210
SMD 2 Digikey
46 RHM47KARCT-ND R53, R58, R60
RES 47K OHM 1/8W 5% 0805
SMD 3 Digikey
47 RHM10KARCT-ND R54, R55, R59
RES 10K OHM 1/8W 5% 0805
SMD 3 Digikey
48 311-10ARCT-ND R61
RES 10 OHM 1/8W 5% 0805
SMD 1 Digikey
49 311-10ARCT-ND R63
RES 10 OHM 1/8W 5% 0805
SMD 1 Digikey
50 360-1758-ND S1
SWITCH TOGGLE SPDT .4VA
SEAL PCB 1 Digikey
51 IR4301M U1, U2
1 CH PowIRaudio integrated
Class D IC 2 IR
52 DDZ5V1BDICT-ND Z1, Z2, Z3, Z4
DIODE ZENER 5.1V 500MW
SOD-123 4 Digikey
53 BZT52C11-FDICT-ND Z5
DIODE ZENER 11V 500MW
SOD123 1 Digikey
54 MMSZ5263BT1GOSCT-
ND Z7
DIODE ZENER 56V 500MW
SOD123 1 Digikey
55 BZT52C36-FDICT-ND Z8*
DIODE ZENER 36V 500MW
SOD123 1 Digikey
*BOM is for 41V-52V power supply
IRAUDAMP19 can be powered by 30V-41V supply with modifications of power resistors and UVP zener as below.
Power supply voltage 41-52V 30-41V
R25~R28,R56,R57,R
64,R65 560 ohm 390 ohm
Z5 36V 27V
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IRAUDAMP19 REV 3.0
PCB Specifications
PCB:
1. Two Layers SMT PCB with through holes
2. 1/16 thickness
3. 2/0 OZ Cu
4. FR4 material
5. 10 mil lines and spaces
6. Solder Mask to be Green enamel EMP110 DBG (CARAPACE) or Enthone Endplate
DSR-3241or equivalent.
7. Silk Screen to be white epoxy non conductive per IPC–RB 276 Standard.
8. All exposed copper must finished with TIN-LEAD Sn 60 or 63 for 100u inches thick.
9. Tolerance of PCB size shall be 0.010 –0.000 inches
10. Tolerance of all Holes is -.000 + 0.003”
11. PCB acceptance criteria as defined for class II PCB’S standards.
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IRAUDAMP19 REV 3.0
PCB Layout
Top side:
Fig 8
Bottom side:
Fig 9
Note: Refer to AN1170 for footprint and board mounting details.
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IRAUDAMP19 REV 3.0
Revision changes descriptions
Revision Changes description Date
Rev 1.0 Released May, 16 2012
Rev 2.0
Rev 3.0
100W version
Housekeeping’s power resistors have been
changed from 1.2kohm to 560ohm
April, 26 2013
October,24 2014
WORLD HEADQUARTERS: 101 N. Sepulveda Blvd., El Segundo, California 90245 Tel: (310) 252-7105
Data and specifications subject to change without notice. 05/16/2012
