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IRAUDAMP7D REV 2.9
IRAUDAMP7D
25W-500W Scalable Output Power
Class D Audio Power Amplifier Reference Design
Using the IRS2092 Protected Digital Audio Driver
By
Jun Honda, Manuel Rodríguez, Wenduo Liu
CAUTION:
International Rectifier suggests the following guidelines for safe operation and handling of
IRAUDAMP7D Demo Board:
Always wear safety glasses whenever operating Demo Board
Avoid personal contact with exposed metal surfaces when operating Demo Board
Turn off Demo Board when placing or removing measurement probes
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IRAUDAMP7D REV 2.9
Item Table of Contents Page
1 Introduction of scalable design ………………………………………………….. 3
2 Power table values for each power model……………………………………… 4
3 Specifications……………………………………………………………………… 4-5
4 Connection setup…………………………………………………………………. 6
5 Test procedure…………………………………………………………………..… 7
6 Performance and test graphs………………………………………………….… 8-13
7 Clipping characteristics…………………………………………………………… 14
8 Efficiency…………………………………………………………………………… 14-16
9 Thermal considerations……………………………………………...…………… 16
10 PSRR, half bridge, full bridge……………………………………………………. 16
11 Short circuit response…………………………………………………………….. 17-18
12 IRAUDAMP7D Overview……………………………………………………….… 18-19
13 Functions Descriptions…………………………………………………………… 20-22
14 Selectable dead Time…………………………………..………………………… 22
15 Protection Features……………………………………………..………………… 22-25
16 Click and pop noise control………………………………………….…………… 25
17 Bus pumping…………………………………………………….………………… 26
18 Bridged configuration……………………………………….……..……………… 27
19 Input signal and Gain……………………………………….……………………. 28
20 Gain settings………………………………………………………………………. 29
21 Schematics………………………………………………………………………… 30-32
22 Bill of Materials………………………………………………………………..…… 33-36
23 IRAUDAMP7D models differential table………………………………………... 36
24 Hardware…………………………………………………………………………… 37-38
25 PCB specifications………………………………………………………………… 39
26 Assembly Drawings………………………………………………………….…… 40
27 Revision changes descriptions………………………………………………….. 41
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IRAUDAMP7D REV 2.9
Introduction
The IRAUDAMP7D reference design is a two-channel Class D audio power amplifier that features output
power scalability. The IRAUDAMP7D offers selectable half-bridge (stereo) and full-bridge (bridged) modes.
This reference design demonstrates how to use the IRS2092 Class D audio driver IC, along with IR’s digital
audio dual MOSFETs, such as IRFI4024H-117P, IRFI4019H-117P, IRFI4212H-117P and IRFI4020H-117P,
on a single layer PCB. The design shows how to implement peripheral circuits on an optimum PCB layout
using a single sided board.
The resulting design requires a small heatsink for normal operation (one-eighth of continuous rated power).
The reference design provides all the required housekeeping power supplies and protections.
Unless otherwise noted, this user’s manual is based on 150V model, IRAUDAMP7D-150,.
Other output power versions can be configured by replacing components given in the component selection
of Table 5 on page 36
Applications
AV receivers
Home theater systems
Mini component stereos
Powered speakers
Sub-woofers
Musical Instrument amplifiers
Automotive after market amplifiers
Features
Output Power: Scalable output power from 25W- 500W (see Table 1)
Residual Noise: 200 V, IHF-A weighted, AES-17 filter
Distortion: 0.05 % THD+N @ 60W, 4 Ω
Efficiency: 90 % @ 500W, 8 Ω, Class D stage
Multiple Protection Features: Over-current protection (OCP), high side and low side MOSFET
Over-voltage protection (OVP),
Under-voltage protection (UVP), high side and low side MOSFET
DC-protection (DCP),
Over-temperature protection (OTP)
PWM topology: Self-oscillating PWM, half-bridge or full-bridge topologies selectable
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IRAUDAMP7D REV 2.9
Table 1 IRAUDAMP7D Specification Table Series
Model Name
Item AMP7D-55 AMP7D-100 AMP7D-150 AMP7D-200
IR Power
MOSFET
FET1A,
FET1B IRFI4024H-117P IRFI4212H-117P IRFI4019H-117P IRFI4020H-117P
8 Ω 25W x 2 60W x 2 125W x 2 250W x 2
Half Bridge 4 Ω 50W x 2 120W x 2 250W x 2 Not Supported
Full Bridge 8 Ω 100W x 1 240W x 1 500W x 1 Not Supported
Nominal
Supply
Voltage
+B, -B ±25V ±35V ±50V ±70V
Min/Max
Supply
Voltage
+B, -B ±20V ~ ±28V ±28V ~ ±45V ±45V ~ ±60V ±60V ~ ±80V
Voltage
Gain Gv 20 30 36 40
Notes:
All the power ratings are at clipping power (THD+N = 1 %). To estimate power ratings at
THD+N=10%, multiply them by 1.33
See Table 5 on page 36 for the complete listing of components table.
Specifications
General Test Conditions for IRAUDAMP7D-150 (unless otherwise noted) Notes / Conditions
Power Supply Voltages ± 50V
Load Impedance 4 Ω
Self-Oscillating Frequency 400kHz
Voltage Gain 36
Electrical Data Typical Notes / Conditions
IR Devices Used IRS2092, Protected digital audio driver
IRFI4024H-117P, IRFI4019H-117P, IRFI4212H-117P, IRFI4020H-
117P Digital audio MOSFETs
PWM Modulator Self-oscillating, second order sigma-delta modulation, analog input
Power Supply Range ± 45V to ± 60V Or see table 1 above
Output Power CH1-2: (1 % THD+N) 300W 1kHz
Output Power CH1-2: (10 % THD+N) 400W 1kHz
Rated Load Impedance 8 - 4 Ω Resistive load
Standby Supply Current +50 mA/-80 mA No input signal
Total Idle Power Consumption 7W No input signal
Channel Efficiency 90 % Single-channel driven, 120W
.
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IRAUDAMP7D REV 2.9
Audio Performance
Before
Demodulator
Class D
Output
Notes / Conditions
THD+N, 1W
THD+N, 10W
THD+N, 60W
THD+N, 100W
0.09 %
0.03 %
0.03 %
0.08 %
0.1 %
0.04 %
0.05 %
0.10 %
1kHz, Single-channel driven
Dynamic Range 100 dB 100 dB A-weighted, AES-17 filter,
Single-channel operation
Residual Noise 200 V 200 V
22 Hz – 20kHz, AES17 filter
Self-oscillating frequency
400kHz
Damping Factor 2000 170 1kHz, relative to 4 Ω load
Channel Separation
95 dB
85 dB
75 dB
90 dB
80 dB
65 dB
100Hz
1kHz
10kHz
Frequency Response : 20 Hz-
20kHz 20 Hz-35kHz ±3 dB 1W, 4 Ω – 8 Ω Load
Thermal Performance (TA=25 C)
Condition Typical Notes / Conditions
Idling TC =30 C
TPCB=37 C No signal input
2 ch x 15W (1/8 rated power) TC =54 C
TPCB=67 C
2 ch x 120W (Rated power) TC =80 C
TPCB=106 C OTP shutdown after 150 s
Physical Specifications
Dimensions 6”(L) x 4”(W) x 1.25”(H)
150 mm (L) x 100 mm (W) x 35 mm(H)
Weight 0.330kgm
Test Setup
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IRAUDAMP7D REV 2.9
Fig 1 Typical Test Setup
Connector Description
CH1 IN RCA1A Analog input for CH1
CH2 IN RCA1B Analog input for CH2
SUPPLY CNN1 Positive and negative supply (+B / -B)
CH1 OUT SPK1A Output for CH1
CH2 OUT SPK1B Output for CH2
Switches Descriptions
S1 Shutdown PWM
S300 Half bridge / Full bridge select
Indicator Description
LED1A, B PWM (presence of low side gate signal)
LED2A,B Protection
SPK1A SPK1B
G
LED1
+B, 5A DC supply
4 Ohm4 Ohm
-B, 5A DC supply
A
udio Si
g
nal
LED2
LED1
LED2
S1 S300
CNN1
RCA1A RCA1B
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IRAUDAMP7D REV 2.9
Test Procedures
Test Setup:
1. On the unit under test (UUT), set switch S1 to OFF and S300 to Stereo positions.
2. Connect 4 -200 W dummy loads to output connectors, SPKR1A and SPKR1B, as shown
on Fig 1.
3. Set up a dual power supply ±50V with 5A current limit
4. Turn OFF the dual power supply before connecting to UUT.
5. Connect the dual power supply to CNN1, as shown in Fig 1.
Power up:
6. Turn ON the dual power supply. The ±B supplies must be applied and removed at the
same time.
7. The red LEDs (Protections) turn ON immediately and stay on as long as S1 is in OFF
position. Blue LEDs stay OFF.
8. Quiescent current for the positive and negative supplies must be less than 50mA, while S1
is in OFF position. Under this condition, IRS2092 is in shutdown mode.
9. Slide S1 to ON position; after one second delay, the two blue LEDs turn ON and the red
LEDs turns off. The two blue LEDs indicate that PWM oscillation is present. This transition
delay time is controlled by CSD pin of IRS2092, capacitor CP3
10. Under the normal operating condition with no input signal applied, quiescent current for the
positive supply must be less than 50 mA; the negative supply current must be less than
100 mA.
Switching Frequency Test:
11. With an oscilloscope, monitor switching waveform at test points VS1 of VS2 and L1B of
CH2. Self oscillating frequency must be 400kHz 25kHz.
Note: The self-oscillating switching frequency is pre-calibrated to 400kHz by the value of
R11. To change switching frequency, change the resistances of R11A and R11B for CH1
and CH2 respectively.
Audio Functionality Tests:
12. Set the signal generator to 1kHz, 20 mVRMS output.
13. Connect audio signal generators to RCA1A and RCA1B.
14. Sweep the audio signal voltage from 15 mVRMS to 1 VRMS.
15. Monitor the output signals at SPK1A/B with an oscilloscope. Waveform must be a non
distorted sinusoidal signal.
16. Observe 1 VRMS input generates output voltage of 36 VRMS. The ratio, R8/(R7+R2),
determines the voltage gain of IRAUDAMP7D.
17. Set switch S300 to Bridged position.
18. Observe that voltage gain doubles.
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IRAUDAMP7D REV 2.9
Test Setup using Audio Precision (Ap):
19. Use unbalance-floating signal generator outputs.
20. Use balanced inputs taken across output terminals, SPKR1A and SPKR1B.
21. Connect Ap frame ground to GND in terminal CNN1.
22. Place AES-17 filter for all the testing except frequency response.
23. Use signal voltage sweep range from 15 mVRMS to 1 VRMS.
24. Run Ap test programs for all subsequent tests as shown in Fig 2- Fig 13 below.
Test Results
0.001
10
0.002
0.005
0.01
0.02
0.05
0.1
0.2
0.5
1
2
5
%
100m 100200m 500m 1 2 5 10 20 50
W
Blue = CH1, Red = CH2
±B Supply = ±25V, 4 Ω Resistive Load
Fig 2 IRAUDAMP7D-55, THD+N versus Power, Stereo, 4 Ω
.
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IRAUDAMP7D REV 2.9
0.001
10
0.002
0.005
0.01
0.02
0.05
0.1
0.2
0.5
1
2
5
%
100m 200200m 500m 1 2 5 10 20 50 100
W
Blue = CH1, Pink = CH2
±B Supply = ±35V, 4 Ω Resistive Load
Fig 3 IRAUDAMP7D-100, THD+N versus Power, Stereo, 4 Ω
.
0.001
10
0.002
0.005
0.01
0.02
0.05
0.1
0.2
0.5
1
2
5
%
100m 500200m 500m 1 2 5 10 20 50 100 200
W
±B Supply = ±35V, 8 Ω Resistive Load, Bridged
Fig 4 IRAUDAMP7D-100, THD+N versus Power, Bridged, 8 Ω
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IRAUDAMP7D REV 2.9
.
0.001
10
0.002
0.005
0.01
0.02
0.05
0.1
0.2
0.5
1
2
5
%
100m 500200m 500m 1 2 5 10 20 50 100 200
W
Blue = CH1, Pink = CH2
±B Supply = ±50V, 4 Ω Resistive Load
Fig 5 IRAUDAMP7D-150, THD+N versus Power, Stereo, 4 Ω
.
0.001
10
0.002
0.005
0.01
0.02
0.05
0.1
0.2
0.5
1
2
5
%
100m 800200m 500m 1 2 5 10 20 50 100 200
W
±B Supply = ±50V, 8 Ω Resistive Load
Fig 6 IRAUDAMP7D-150, THD+N versus Power, Bridged 8 Ω
.
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IRAUDAMP7D REV 2.9
Blue = CH1, Red = CH2
±B Supply = ±70V, 8 Ω Resistive Load
Fig 7 IRAUDAMP7D-200, THD+N versus Power, Stereo 8 Ω
.
-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
Red CH1 - 4 Ω, 2 V Output referenced
Blue CH1 - 8 Ω, 2 V Output referenced
Fig 8 Frequency Response (All Models)
.
0.001
10
0.002
0.005
0.01
0.02
0.05
0.1
0.2
0.5
1
2
5
%
100m 500 200m 500m 1 2 5 10 20 50 100 200
W
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IRAUDAMP7D REV 2.9
0.0001
100
0.001
0.01
0.02
0.05
0.1
0.5
1
10
50
%
20 20k50 100 200 500 1k 2k 5k 10k
Hz
Blue CH1, 10W Output
Pink CH1, 50W Output
Fig 9 IRAUDAMP7D-150, THD+N versus Frequency, 4Ω
.
-110
+0
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
V
20 20k50 100 200 500 1k 2k 5k 10k
Hz
1V Output
Fig 10 IRAUDAMP7D-150, 1 kHz – 1 V Output Spectrum, Stereo
.
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IRAUDAMP7D REV 2.9
-110
+0
-100
-90
-80
-70
-60
-50
-40
-30
-20
-10
d
B
V
20 20k50 100 200 500 1k 2k 5k 10k
Hz
1V Output
Fig 11 IRAUDAMP7D-150, 1 kHz - 1V Output Spectrum, Bridged
.
-140
+20
-120
-100
-80
-60
-40
-20
+0
d
B
V
10 20k20 50 100 200 500 1k 2k 5k 10k
Hz
Red CH1 - ACD, No signal, Self Oscillator @ 400kHz
Blue CH2 - ACD, No signal, Self Oscillator @ 400kHz
Fig 12 IRAUDAMP7D-150 Noise Floor
.
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IRAUDAMP7D REV 2.9
.
60 W / 4 , 1 kHz, THD+N = 0.02 % 250 W / 4 , 1 kHz, THD+N = 10 %
Measured Output and Distortion Waveforms
Fig 13 Clipping Characteristics
.
Efficiency
Figs 14-19 show efficiency characteristics of the IRAUDAMP7D. The high efficiency is achieved by
following major factors:
1) Low conduction loss due to the dual FETs offering low RDS(ON)
2) Low switching loss due to the dual FETs offering low input capacitance for fast rise and fall
times
3) Secure dead-time provided by the IRS2092, avoiding cross-conduction
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 102030405060
Output power (W)
Efficiency (%
)
25V-4ohms
±B Supply = ±25 V
Fig 14 Efficiency versus Output Power, IRAUDAMP7D-55, 4 Ω, Stereo
Red Trace: Total Distortion + Noise Voltage
Gold Trace: Output Voltage
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IRAUDAMP7D REV 2.9
.
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 20406080100120140160
Output power (W)
Efficiency (%)
35V-4ohms
±B Supply = ±35 V
Fig 15 Efficiency versus Output Power, IRAUDAMP7D-100, 4 Ω, Stereo
.
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 50 100 150 200 250 300
Output power (W)
Efficiency (%
)
35V-8ohms-Full bridge
±B Supply = ±35V
Fig 16 Efficiency versus Output Power, IRAUDAMP7D-100, 8 Ω, Bridged
.
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
0 50 100 150 200 250 300
Output power (W)
Efficiency (%)
50V-4ohms
±B Supply = ±50V
Fig 17 Efficiency versus Output Power, IRAUDAMP7D-150, 4 Ω, Stereo
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IRAUDAMP7D REV 2.9
.
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 50 100 150 200 250 300 350 400 450 500 550
Output power (W)
Efficiency (%
)
50V-8ohms-Full bridge
±B Supply = ±50V
Fig 18 Efficiency versus Output Power, IRAUDAMP7D-150, 8 Ω, Bridged
.
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0 50 100 150 200 250 300
Output power (W)
Efficiency (%
)
70V-8ohms
±B supply = ±70V
Fig 19 Efficiency versus Output Power, IRAUDAMP7D-200, 8 Ω, Stereo
Thermal Considerations
With this high efficiency, the IRAUDAMP7D design can handle one-eighth of the continuous rated
power, which is generally considered to be a normal operating condition for safety standards,
without additional heatsink or forced air-cooling.
Power Supply Rejection Ratio (PSRR)
The IRAUDAMP7D obtains good power supply rejection ratio of -65 dB at 1kHz shown in Fig 20.
With this high PSRR, IRAUDAMP7D accepts any power supply topology as far as the supply
voltages fit in the min and max range.
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IRAUDAMP7D REV 2.9
Cyan: VAA & VSS are fed by +/-B bus
Green: VAA & VSS are fed by external +/-5 V regulated power supplies.
Fig 20 IRAUDAMP7D Power Supply Rejection Ratio
Short Circuit Protection Response
Figs 21-23 show over current protection reaction time of the IRAUDAMP7D in a short circuit event.
As soon as the IRS2092 detects over current condition, it shuts down PWM. After one second, the
IRS2092 tries to resume the PWM. If the short circuit persists, the IRS2092 repeats try and fail
sequences until the short circuit is removed.
Short Circuit in Positive and Negative Load Current
Fig 21 Positive and Negative OCP Waveforms
.
Load current
CSD
p
in
Load current
Positive OCP
CSD
p
in
VS
p
in
Negative OCP
VS
p
in
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IRAUDAMP7D REV 2.9
OCP Waveforms Showing CSD Trip and Hiccup
.
Fig 22 OCP Response with Continuous Short Circuit
.
Actual Reaction Time
OCP Waveforms Showing actual reaction time
.
Fig. 23 High and Low Side OCP current waveform reaction time
IRAUDAMP7D Overview
The IRAUDAMP7D features a self-oscillating type PWM modulator for the lowest component
count, highest performance and robust design. This topology represents an analog version of a
second-order sigma-delta modulation having a Class D switching stage inside the loop. The
Load current
CSD
p
in
Load current
CSD
p
in
VS
p
in VS
p
in
Load current
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IRAUDAMP7D REV 2.9
benefit of the sigma-delta modulation, in comparison to the carrier-signal based modulation, is that
all the error in the audible frequency range is shifted to the inaudible upper-frequency range by
nature of its operation. Also, sigma-delta modulation allows a designer to apply a sufficient
amount of error correction.
The IRAUDAMP7D self-oscillating topology consists of following essential functional blocks.
Front-end integrator
PWM comparator
Level shifters
Gate drivers and MOSFETs
Output LPF
Integrator
Referring to Fig 24 below, the input operational amplifier of the IRS2092 forms a front-end second-
order integrator with R7, C4, C6, and R11. The integrator that receives a rectangular feedback
signal from the PWM output via R8 and audio input signal via R7 generates quadratic carrier
signal in COMP pin. The analog input signal shifts the average value of the quadratic waveform
such that the duty cycle varies according to the instantaneous voltage of the analog input signal.
PWM Comparator
The carrier signal in COMP pin is converted to PWM signal by an internal comparator that has
threshold at middle point between VAA and VSS. The comparator has no hysteresis in its input
threshold.
Level Shifters
The internal input level-shifter transfers the PWM signal down to the low-side gate driver section.
The gate driver section has another level-shifter that level shifts up the high-side gate signal to the
high-side gate driver section.
Gate Drivers and MOSFETs
The received PWM signal is sent to the dead-time generation block where a programmable
amount of dead time is added into the PWM signal between the two gate output signals of LO and
HO to prevent potential cross conduction across the output power MOSFETs. The high-side level-
shifter shifts up the high-side gate drive signal out of the dead-time block.
The IRS2092 drives two MOSFETs, high- and low-sides, in the power stage providing the
amplified PWM waveform.
Output LPF
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IRAUDAMP7D REV 2.9
The amplified PWM output is reconstructed back to analog signal by the output LC LPF.
Demodulation LC low-pass filter (LPF) formed by L1 and C12, filters out the Class D switching
carrier signal leaving the audio output at the speaker load. A single stage output filter can be used
with switching frequencies of 400 kHz and greater; a design with a lower switching frequency may
require an additional stage of LPF.
+
-
.
-B
.
.
R7
IN-
COMP
C6
.
-VSS
+VAA
LO
VS
VCC
D3
CP6
VB 0V
+B
0V
R11
C7
R117
CP5
HO
C12
INPUT
C4
R8
R118
CP2
+VCC
Integrator
COM
R25
Modulator
and
Shift level
GND
0V
-B
0VLP Filter
L1
CP4
R24
IRS2092
+B
IRFI4019H-117P
IRFI4212H-117P
FET1
IRFI4020H-117P
IRFI4024H-117P
Fig 24 Simplified Block Diagram of IRAUDAMP7D Class D Amplifier
Functional Descriptions
IRS2092 Gate Driver IC
The IRAUDAMP7D uses IRS2092, a high-voltage (up to 200 V), high-speed power MOSFET
driver with internal dead-time and protection functions specifically designed for Class D audio
amplifier applications. These functions include OCP and UVP. The IRS2092 integrates bi-
directional over current protection for both high-side and low-side MOSFETs. The dead-time can
be selected for optimized performance according to the size of the MOSFET, minimizing dead-
time while preventing shoot-through. As a result, there is no gate-timing adjustment required
externally. Selectable dead-time through the DT pin voltage is an easy and reliable function which
requires only two external resistors, R26 and R27 as shown on Fig 25 below.
The IRS2092 offers the following functions.
PWM modulator
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IRAUDAMP7D REV 2.9
Dead-time insertion
Over current protection
Under voltage protection
Level shifters
Refer to IRS2092 datasheet and AN-1138 for more details.
R13
10k
R12
8.7k
R21
10R
R25
20R
R24
20R
R19
10k
R18
9.6k
R22
10K C11
0.1uF,100V
R17
75k
-B
VCC
R23
4.7K
10uF
CP3
R11
270R
C6
1nF
C4
1nF
R20
4.7R
LO 11
VS 13
HO 14
VCC 12
GND
2
VAA
1
COM 10
DT 9
OCSET
8
IN-
3
COMP
4
CSD
5
VSS
6
VREF
7
VB 15
CSH 16
U1
IRS2092S DIP
C7 1nF VS1
22uF
CP6
22uF
CP5
22uF
CP4
22uF
CP2
10uF
CP1
CP8
470uF,100V
CP7
470uF,100V
L1
22uH
R31
2.2k
C13
0. 1uF, 400V
R30
10, 1W
C12
0. 47uF, 40 0V
+
-
CH1
R8
100k
3
5
2
1
4
FET1
1
2
SPKR1
R2
3.3k
RCA1
Blue
LED1
CH_OUT
C14
0.1uF
R117
3. 3k 1w
R118
3. 3k 1w
-B
+B
D3
D4
R26
10k
R27
10k
-B
D1
R3
100R
SD
Fig 25 System-level View of IRAUDAMP7D
Self-Oscillating Frequency
Self-oscillating frequency is determined by the total delay time along the control loop of the
system; the propagation delay of the IRS2092, the MOSFETs switching speed, the time-constant
of front-end integrator (R7, R8, R11, C4, C6, C7). Variations in +B and –B supply voltages also
affect the self-oscillating frequency.
The self-oscillating frequency changes with the duty ratio. The frequency is highest at idling. It
drops as duty cycle varies away from 50%.
Adjustments of Self-Oscillating Frequency
Use R11 to set different self-oscillating frequencies. The PWM switching frequency in this type of
self-oscillating switching scheme greatly impacts the audio performance, both in absolute
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IRAUDAMP7D REV 2.9
frequency and frequency relative to the other channels. In the absolute terms, at higher
frequencies distortion due to switching-time becomes significant, while at lower frequencies, the
bandwidth of the amplifier suffers. In relative terms, interference between channels is most
significant if the relative frequency difference is within the audible range.
Normally, when adjusting the self-oscillating frequency of the different channels, it is suggested to
either match the frequencies accurately, or have them separated by at least 25kHz. Under the
normal operating condition with no audio input signal, the switching-frequency is set around
400kHz in the IRAUDAMP7D.
Selectable Dead-time
The dead-time of the IRS2092 is set based on the voltage applied to the DT pin. Fig 26 lists the
suggested component value for each programmable dead-time between 25 and 105 ns.
All the IRAUDAMP7D models use DT2 (45ns) dead-time.
Dead-time Mode R1 R2 DT/SD Voltage
DT1 <10k Open Vcc
DT2 5.6k 4.7k 0.46 x Vcc
DT3 8.2k 3.3k 0.29 x Vcc
DT4 Open <10k COM
Recommended Resistor Values for Dead Time Selection
Vcc 0.57xVcc 0.36xVcc 0.23 xVcc
105nS
75nS
45nS
25nS
VDT
Dead- time
Vcc
COM
DT
>0.5mA
R1
R2
IRS2092(S)
Fig 26 Dead-time Settings vs. VDT Voltage
Protection System Overview
The IRS2092 integrates over current protection (OCP) inside the IC. The rest of the protections,
such as over-voltage protection (OVP), under-voltage protection (UVP), speaker DC offset
www.irf.com Page 23 of 41
IRAUDAMP7D REV 2.9
protection (DCP) and over temperature protection (OTP), are realized externally to the IRS2092
(Fig 27).
In the event that any of these external fault conditions are detected, the external shutdown circuit
will disable the output by pulling down CSD pins, turning on red LEDs, and turning off blue LEDs
(Fig 28). If the fault condition persists, the protection circuit stays in shutdown until the fault is
removed. Once the fault is cleared, the blue LEDs turn on and red LEDs turn off.
Q100
2N3904
CH1 _ OUT
CH2 _ OUT
-VSS1
330uF, 10V
CP100
Z100
*68V
+B
-VSS1
R112
47K
SD
DCP
OVP
UVP
OTP
R103
715R
Q101
2N3906
T H 100 i s the rm al ly c onne ct ed wit h H e a t s i nk
-VSS1
-VSS1 +B
TH100
2.2k
12
3
54
6
S1
SW DP DT
R104
4.7k
R101
4.7k
R102
10k
C100
0.1uF
R113
10k
R107
10k
R105
10k
R11 1
10k
R108
100k
R109
100k
R110
100k
Z101
*39V
Q104
2N3904
Q102
2N3906
Q103
2N3906
JW3
R106
10k
Fig 27 DCP, OTP, UVP and OVP Protection Circuits
.
. .
+VAA
OCREF
OCREF
5.1V
CSD
OCSET
+
.
LO
VS
VCC
VB
CSH
R19
LED1
BLUE
D4
BAV19
LP Filter
PROT
RED
CP3
R12
HO
OCSET COM
-VSS
CSD
1.2V
R18
+B
R13
R17
-B
FET1
FET2
Fig 28 Simplified Functional Diagram of OCP and Associated LED Indicators
www.irf.com Page 24 of 41
IRAUDAMP7D REV 2.9
Over-Current Protection (OCP)
Low-Side Current Sensing
The low-side current sensing feature protects the low side MOSFET from an overload condition in negative
load current by measuring drain-to-source voltage across RDS(ON) during its on state. OCP shuts down the
switching operation if the drain-to-source voltage exceeds a preset trip level.
The voltage setting on the OCSET pin programs the threshold for low-side over-current sensing. When the
VS voltage during low-side conduction gets higher than the OCSET voltage, the IRS2092 turns off outputs
and pulls CSD down to -VSS.
High-Side Current Sensing
The high-side current sensing protects the high side MOSFET from an overload condition in
positive load current by measuring drain-to-source voltage across RDS(ON) during its on state. OCP
shuts down the switching operation if the drain-to-source voltage exceeds a preset trip level.
High-side over-current sensing monitors drain-to-source voltage of the high-side MOSFET while it
is in the on state through the CSH and VS pins. The CSH pin detects the drain voltage with
reference to the VS pin, which is the source of the high-side MOSFET. In contrast to the low-side
current sensing, the threshold of CSH pin to trigger OC protection is internally fixed at 1.2V. An
external resistive divider R19, R18 and R17 are used to program a threshold as shown in Fig 26.
An external reverse blocking diode D4 is required to block high voltage feeding into the CSH pin
during low-side conduction. By subtracting a forward voltage drop of 0.6V at D4, the minimum
threshold which can be set for the high-side is 0.6V across the drain-to-source.
Table 2 Actual OCP table setting thresholds
Function Device Amp7-55 Amp7-100 Amp7-150 Amp7-200
OCSET
R12A
R12B 1.3K 3.9K 7.5K 5.2K
Tested OCP current 25oC 23A 30A 23A
CSH
R18A
R18B 0.0 4.7K 9.6K 8.2K
Tested OCP current 25oC 23A 29A 23A
Peak load current
at rated power 6.0A 8.7A 12.2A 8.9A
Over-Voltage Protection (OVP)
OVP is provided externally to the IRS2092. OVP shuts down the amplifier if the bus voltage
between GND and +B exceeds 75V. The threshold is determined by a Zener diode Z100. OVP
www.irf.com Page 25 of 41
IRAUDAMP7D REV 2.9
protects the board from harmful excessive supply voltages, such as due to bus pumping at very
low frequency continuous output in stereo mode.
Under-Voltage Protection (UVP)
UVP is provided externally to the IRS2092. UVP prevents unwanted audible noise output from
unstable PWM operation during power up and down. UVP shuts down the amplifier if the bus
voltage between GND and +B falls below a voltage set by Zener diode Z101.
Speaker DC-Voltage Protection (DCP)
DCP protects speakers against DC output current feeding to its voice coil. DC offset detection
detects abnormal DC offset and shuts down PWM. If this abnormal condition is caused by a
MOSFET failure because one of the high-side or low-side MOSFETs short circuited and remained
in the on state, the power supply needs to be cut off in order to protect the speakers. Output DC
offset greater than ±4V triggers DCP.
Offset Null (DC Offset) Adjustment
The IRAUDAMP7D requires no output-offset adjustment. DC offsets are tested to be less than ±20
mV.
Over-Temperature Protection (OTP)
A NTC resistor, TH100 in Fig 25, is placed in close proximity to two dual MOSFETs on a heatsink
to monitor heatsink temperature. If the heatsink temperature rises above 100 C, the OTP shuts
down both channels by pulling down CSD pins of the IRS2092. OTP recovers once the
temperature has cooled down.
ON-OFF Switch
OFF position of S1 forces the IRAUDAMP7D to stay in shutdown mode by pulling down the CSD
pin. During the shutdown mode the output MOSFETs are kept off.
Click and POP Noise Reduction
Thanks to the click and pop elimination function built into the IRS2092, IRAUDAMP7D does not
use any additional components for this function.
www.irf.com Page 26 of 41
IRAUDAMP7D REV 2.9
Power Supply Requirements
For convenience, the IRAUDAMP7D has all the necessary housekeeping power supplies onboard
and only requires a pair of symmetric power supplies. Power supply voltage depends on the model
and is shown in the power selection in Table 1.
House Keeping Power Supply
The internally-generated housekeeping power supplies include ±5.6V for analog signal processing,
and +12V supply (VCC) referred to negative supply rail -B for MOSFET gate drive. The VAA and
VSS supplying floating input section are fed from +B and -B power stage bus supplies via R117
and R118, respectively. Gate driver section of IRS2092 uses VCC to drive gates of MOSFETs.
The VCC is referenced to –B (negative power supply). D3 and CP6 form a bootstrap floating supply
for the HO gate driver.
Bus Pumping
When the IRAUDAMP7D is running in the stereo mode, bus pumping effect takes place with low
frequency high output. Since the energy flowing in the Class D switching stage is bi-directional,
there is a period where the Class D amplifier feeds energy back to the power supply. The majority
of the energy flowing back to the supply is from the energy stored in the inductor in the output LPF.
Usually, the power supply has no way to absorb the energy coming back from the load.
Consequently the bus voltage is pumped up, creating bus voltage fluctuations.
Following conditions make bus pumping worse:
1. Lower output frequencies (bus-pumping duration is longer per half cycle)
2. Higher power output voltage and/or lower load impedance (more energy transfers between
supplies)
3. Smaller bus capacitance (the same energy will cause a larger voltage increase)
The OVP protects IRAUDAMP7D from failure in case of excessive bus pumping. One of the
easiest counter measures of bus pumping is to drive both of the channels in a stereo configuration
out-of-phase so that one channel consumes the energy flow from the other and does not return it
to the power supply. Bus voltage detection monitors only +B supply, assuming the bus pumping
on the supplies is symmetric in +B and -B supplies.
There is no bus pumping effect in full bridge mode.
www.irf.com Page 27 of 41
IRAUDAMP7D REV 2.9
Cyan: Positive Rail voltage (+B), Green: Speaker Output, Pink: Negative Rail voltage (-B)
Fig 29 Bus Pumping in Half Bridge Mode
Bridged Configuration
By selecting S300 to Bridged position, the IRAUDAMP7D realizes full bridge mode, also known as
bridge-tied-load, or BTL configuration. Full bridge operation is achieved by feeding out-of-phase
audio input signals to the two input channels as shown in the Fig 30 below.
In bridged mode, IRAUDAMP7D receives audio input signal from channel A only. The on-board
inverter feed out-of-phase signal to Channel B. The speaker output must be connected between
(+) of Channel A and (+) of Channel B in bridged mode.
In bridged mode, nominal load impedance is 8 Ω. (See power table in Table 1)
.
R300
22k
R302
100
C300
0.1uF
R303
100
C301
0.1uF
+VAA
-VSS
1
6
5
2
3
8
74
U300
TL072CP
R301
22k
From Ch A
Bridged
Steereo
RCA2
RCA1 JW8
CP1B+
From Ch B
12
3
54
6
S300
SW DPDT
Fig 30 Bridged Configuration (BTL)
www.irf.com Page 28 of 41
IRAUDAMP7D REV 2.9
Load Impedance
Each channel is optimized for a 4 Ω speaker load in half bridge and 8 Ω load in full bridge.
Output Filter Selection
Since the output filter is not included in the control loop of the IRAUDAMP7D, the control loop has
no ability to compensate performance deterioration caused by the output filter. Therefore, it is
necessary to understand what characteristics are preferable when designing the output filter.
1) The DC resistance of the inductor should be minimized to 20 mΩ or less.
2) The linearity of the output inductor and capacitor should be high with output current and
voltage.
Fig 31 demonstrates THD performance difference with various inductors.
Fig 31 THD+N vs. Output Power with Different kind of Output Inductors
0.0001
100
0.001
0.01
0.1
1
10
%
100m 200m 500m 1 2 5 10 20 50 100 200
W
T T
www.irf.com Page 29 of 41
IRAUDAMP7D REV 2.9
Input Signal and Gain Setting
A proper input signal is an analog signal ranging from 20Hz to 20kHz with up to 3 VRMS amplitude
with a source impedance of no more than 600 Ω. Input signal with frequencies from 30kHz to
60kHz may cause LC resonance in the output LPF, causing a large reactive current flowing
through the switching stage, especially with greater than 8 Ω load impedances, and the LC
resonance can activate OCP.
The IRAUDAMP7D has an RC network called Zobel network (R30 and C13) to damp the
resonance and prevent peaking frequency response with light loading impedance. (Fig 32) The
Zobel network is not thermally rated to handle continuous supersonic frequencies above 20kHz.
These supersonic input frequencies can be filtered out by adding R2 and C2 as shown on main
schematic Fig 33 and Fig 34. This RC filter works also as an input RF filter to prevent potential
radio frequency interferences.
.
.
.
.
0V
0V
LP Filter
L1 C12
R30
C13
Fig 32 Output Low Pass Filter and Zobel Network
Gain Setting
The ratio of resistors R8/R2 in Fig 23 sets voltage gain. The IRAUDAMP7D has no on board volume control.
To change the voltage gain, change the input resistor term R2. Changing R8 affects PWM control loop
design and may result poor audio performance.
www.irf.com Page 30 of 41
IRAUDAMP7D REV 2.9
D1A
R3A
100R
R13A
10k
R12A
*7.5k
R24A
20R
R18A
*9.1k C11A
0.1uF,100V
R17A
*47k +B
-B
SD
VCC1
CP3A
10uF
R11A
*300R
C4A
1nF
R20A
4.7R
C8A
150pF,250V
LO 11
VS 13
HO 14
VCC 12
GND
2
VAA
1
COM 10
DT 9
OCSET
8
IN-
3
COMP
4
CSD
5
VSS
6
VREF
7
VB 15
CSH 16
U1A
IRS2092PbF
VS1
CP6A
22uF
Drawing by: M.Rodriguez Mrodrig5@irf.com
R7A
*3. 01k 1%
CP8A
*470uF, 100V
L1A
22uH
CHA, OUT
R31A
2.2k
C13A
0. 1uF, 400V
R30A
10, 1W
C12A
0. 47uF, 400V
-B
+B
+
-
CHA
R8A
*120k 1%
Feedback
*IRFI4019H-117P
3
5
2
1
4
FET1A
1
2
SPKR1A
RCA1A
Z1A
15V
R1A
100k
Blue LED
LED1A
CH1_OUT
HS1
JW1A
Z103A
5.6V
R117A
*3. 3k 1w
R114A
*1k 1w
1
23
TIP31CQ105A
-B
+B
3
2
1
FET2A
BS250P
R14A
4.7k
Pr ot A
Red LED
RCA1
D3A
Heat si nk
-B
Note: Components values marked on red or * are according to power table
R2 & C2 are RF fi lt ers, opti onal
Note:
IRAUDAMP7-55, +B,-B are +/-25V with FET1 as IRFI4024H-117P
IRAUDAMP7-100, +B ,-B are +/-35V with FET1 as IRFI4212H-117P
IRAUDAMP7-150, +B ,-B are +/-50V with FET1 as IRFI4019H-117P
IRAUDAMP7-200, +B ,-B are +/-70V with FET1 as IRFI4020H-117P
D5A
+VAA1
-VSS1
R22A
10k
R19A
10k
R27A
10k
R26A
10k
R115A
*15k
R23A
10k
R2A
330
Z104A
5.6V
D4A
D6A
Z102A
15V
IRAUDAMP7 Rev 2.2
R28A10R
JW2A
R118A
*3. 3k 1w
CP1A
22uF
CP2A
22uF
CP4A
22uF
CP5A
22uF
CP101A22uF
C9A
open
CP7A
*470uF, 100V
C14A
0.1uF,100V
C2A
1nF
C6A
1nF C7A
1nF
C10A
0. 1uF , 400V
+B
+B
-B
1
2
3
CONN1
22uH
R25A
20R
R29Aopen
R21A
10R
CHA
Fig 33 Amplifier Schematic, Channel 1
.
www.irf.com Page 31 of 41
IRAUDAMP7D REV 2.9
D1B
R3B
100R
R13B
10k
R12B
*7.5k
R18B
*9.1k C11B
0.1uF,100V
R17B
*47k +B
-B
SD
VCC2
CP3B
10uF
R11B
*270R
C4B
1nF
R20B
4.7R
C8B
150pF,250V
LO 11
VS 13
HO 14
VCC 12
GND
2
VAA
1
COM 10
DT 9
OCSET
8
IN-
3
COMP
4
CSD
5
VSS
6
VREF
7
VB 15
CSH 16
U1B
IRS2092PbF
VS2
CP6B
22uF
R7B
*3.01k 1%
CP8B
*470uF, 100V
L1B
22uH
CH2 OUT
R31B
2.2k
C13B
0.1uF, 400V
R30B
10, 1W
C12B
0.47uF, 400V
-B
+B
+
-
CH1
R8B
*100k 1%
Feedback
*IRFI4019H-117P
3
5
2
1
4
FET1B
1
2
SPKR1B
RCA1B
Z1B
15V
R1B
100k
Blue LED
LED1B
CH2_OUT
JW1B
Z103B
5.6V
R117B
*3.3k 1w
R114B
*1k 1w
1
23
TIP31CQ105B
-B
+B
3
2
1
FET2B
BS250P
R14B
4.7k
Prot B
Red L ED
RCA1
D3B
Heat s i n k
-B
Note: C omponents val ues marked on red or * are according to power tabl e
R2 & C2 are RF filte rs, optiona l
Note:
IRAUDAMP7-55, +B ,-B are +/-25V with FET1 as IRFI4024H-117P
IRAUDAMP7-100, +B ,-B are +/-35V with FET1 as IRFI4212H-117P
IRAUDAMP7-150, +B ,-B are +/-50V with FET1 as IRFI4019H-117P
IRAUDAMP7-200, +B ,-B are +/-70V with FET1 as IRFI4020H-117P
D5B
+VAA2
-VSS2
R22B
10k
R19B
10k
R27B
10k
R26B
10k
R115B
*10k
R23B
10k
R2B
330
Z104B
5.6V
D4B
D6B
Z102B
15V
JW2B
R118B
*3.3k 1w
CP1B
22uF
CP2B
22uF
CP4B
22uF
CP5B
22uF
CP101B22uF
C9B
open
CP7B
*470uF, 100V
C14B
0.1uF,100V
C2B
1nF
C6B
1nF C7B
1nF
C10B
0.1uF, 400V
+B
L2
22uH
R24B
20R
R25B
20R
R28B10R R29B
open
R21B
10R
Fig 34 Amplifier Schematic, Channel 2
.
www.irf.com Page 32 of 41
IRAUDAMP7D REV 2.9
Drawing by: M.Rodriguez Mrodrig5@irf.co
m
Q100
2N3904
CH1_OUT
CH2_OUT
-VSS1
330uF, 10V
CP100
Z100
*68V
+B
-VSS1
R112
47K
SD
DCP
OVP
UVP
OTP
R103
715R
Q101
2N3906
T H 100 i s t he rm al l y c onnec t ed wi th Hea t s i nk
-VSS1
-VSS1 +B
JW5
JW6
JW7
SD SD
+B +B
-B -B
TH100
2.2k
JW20
JW21
VCC1
VCC2
VCC2
VCC2
Note: Components values ma rked on r ed or * are according to power table
12
3
54
6
S1
SW DPDT
R104
4.7k
R101
4.7k
R102
10k
C100
0.1uF
R113
10k
R107
10k
R105
10k
R111
10k
R108
100k
R109
100k
R110
100k
Z101
*39V
Q104
2N3904
Q102
2N3906
Q103
2N3906
JW3
R106
10k
Fig 35 Protection Schematic
.
R300
22k
+VAA2
-VSS2
1
6
5
2
3
8
74
U300
TL071CP
From CHA, RCA input
Bridged
Steereo
RCA2
RCA1
CP1B+
Drawing by: M.Rodriguez Mrodrig5@irf.co
m
From CH2, RCA input
12
3
54
6
S300
SW D PDT
R301
22k
R302
100
R303
100
C300
0.1uF
C301
0.1uF
JW8
JW9
Fig 36 Bridge Preamp Schematic
www.irf.com Page 33 of 41
IRAUDAMP7D REV 2.9
IRAUDAMP7D-150 Fabrication Materials
Table 3 IRAUDAMP7D-150 Electrical Bill of Materials
Quantit
y Value Description Designator Digikey P/N Vendor
8 1nF, 50V CAP 1nF 50V
POLYESTER 5%
C2A, C2B, C4A,
C4B, C6A, C6B,
C7A, C7B
P4551-ND Panasonic -
ECG
2 150 pF, 250V
CERAMIC CAP 150PF
250 VAC CERAMIC
10 %
C8A, C8B P11413TB-ND Panasonic -
ECG
2 Open
CERAMIC CAP 150PF
250 VAC CERAMIC
10%
C9A, C9B P11413TB-ND Panasonic -
ECG
4 0.1uF, 400V
CAP .10UF 400V
METAL
POLYPROPYLANE
C10A, C10B, C13A,
C13B 495-1311-ND EPCOS Inc
4 0.1uF 100V CAP .10UF 100V
METAL POLYESTER
C11A, C11B, C14A,
C14B 495-1147-ND EPCOS Inc
2 0.47uF,
400V
CAP .47UF 400V
METAL
POLYPROPYLANE
C12A, C12B 495-1315-ND EPCOS Inc
3 0.1uF 100V CAP .10UF 100V
METAL POLYESTER C100, C300, C301 495-1147-ND EPCOS Inc
1 ED365/3
TERMINAL BLOCK
7.50MM 3POS PCB CONN1 ED2355-ND
On Shore
Technology
12 22uF
CAP 22UF 25V ELECT
VR RADIAL
CP1A, CP1B, CP2A,
CP2B, CP4A, CP4B,
CP5A, CP5B, CP6A,
CP6B, CP101A,
CP101B
493-1058-ND Nichicon
2 10uF, 16V
CAP ELECT 10UF 16V
KS RADIAL CP3A, CP3B P966-ND Panasonic -
ECG
4 470uF/100V CAP 470UF 100V
ELECT PW RADIAL
CP7A, CP7B, CP8A,
CP8B 493-1985-ND Nichicon
1 330uF, 10V
CAP 330UF 10V ALUM
LYTIC RADIAL CP100 P5125-ND
Panasonic -
ECG
2 1N4148T-73
DIODE SWITCH 100V
150MA DO-35 D1A, D1B 1N4148T-73CT-ND Rohm
4 MUR120RLG
DIODE ULTRA FAST
1A 200V AXIAL DO-41 D3A, D3B, D4A, D4B MUR120RLGOSCT
-ND
ON
Semiconducto
r
4 1N4003
DIODE GEN PURPOSE
200V 1A DO41 D5A, D5B, D6A, D6B 1N4003FSCT-ND
Fairchild
Semiconducto
r
2 *IRFI4019H-
117P
IRFI4019H-117P, Dual
MOSFET TO-220-5 FET1A, FET1B IR's Part No. International
Rectifier
2 BS250P
MOSFET P-CH 45V
230MA TO-92 FET2A, FET2B BS250P-ND Zetex Inc
1 Heat sink Aluminum heat spreader HS1 Drawing
IRHS_Amp1 Custom made
4 Wire 0.400"
AXIAL JUMPER RES
0.0 OHM
JW1A, JW1B, JW2A,
JW2B P0.0BACT-ND Panasonic -
ECG
1 Wire 0.300"
AXIAL JUMPER RES
0.0 OHM JW3 P0.0BACT-ND
Panasonic -
ECG
1 Wire 1.640"
Wire Jumper #20 AWG
insulated JW5 Custom Custom
2 Wire 1.800"
Wire Jumper #20 AWG
insulated JW6, JW7 Custom Custom
1 Wire 1.240"
Wire Jumper #20 AWG
insulated JW8 Custom Custom
1 Wire 1.200"
Wire Jumper #20 AWG
insulated JW9 Custom Custom
2 Wire 0.800"
Wire Jumper #20 AWG
insulated JW20, JW21 Custom Custom
2 22uH, 13A Class D Inductor, 22UH L1A, L1B Sagami 7G17A- Sagami
www.irf.com Page 34 of 41
IRAUDAMP7D REV 2.9
13A 220M-R
2 Blue LED LED 3MM DUAL
FLANGE BLUE CLEAR LED1A, LED1B 160-1600-ND LITE-ON INC
2 Red LED
LED 3MM HI-EFF RED
TRANSPARENT Prot A, Prot B 160-1140-ND LITE-ON INC
2 2N3904-AP
TRANSISTOR NPN GP
40V TO92 Q100, Q104 2N3904-APCT-ND
Micro
Commercial
Co.
3 2N3906-AP
TRANSISTOR PNP GP
40V TO92 Q101, Q102, Q103 2N3906-APCT-ND
Micro
Commercial
Co.
2 TIP31C
TRANS NPN EPITAX
100V 3A TO-220 Q105A, Q105B TIP31CFS-ND
Fairchild
Semiconducto
r
4 100k
RES 100K OHM
CARBON FILM 1/4W
5%
R1A, R1B, R108,
R110 P100KBACT-ND Panasonic -
ECG
2 330
AXIAL RES 330 OHM
CARBON FILM 1/4W
5%
R2A, R2B P330BACT-ND Panasonic -
ECG
2 100 Ohms
AXIAL RES 100 OHM
CARBON FILM 1/4W
5%
R3A, R3B P100BACT-ND Panasonic -
ECG
2 3k 1%
AXIAL RES METAL
FILM 3.00K OHM 1/4W
1%
R7A, R7B P3.00KCACT-ND Panasonic -
ECG
2 120k 1%
AXIAL RES METAL
FILM 120K OHM 1/4W
1%
R8A, R8B P120KCACT-ND Panasonic -
ECG
2 300 Ohms
AXIAL RES 300 OHM
CARBON FILM 1/4W
5%
R11A, R11B P300BACT-ND P300BACT-
ND
2 7.5k
AXIAL RES 7.5K OHM
CARBON FILM 1/4W
5%
R12A, R12B P7.5KBACT-ND Yageo
18 10k
AXIAL RES 10k OHM
CARBON FILM 1/4W
5%
R13A, R13B, R19A,
R19B, R22A, R22B,
R23A, R23B, R26A,
R26B, R27A, R27B,
R102, R105, R106,
R107, R111, R113
P10KBACT-ND Panasonic -
ECG
4 4.7k
AXIAL RES 4.7K OHM
CARBON FILM 1/4W
5%
R14A, R14B, R101,
R104 P4.7KBACT-ND Panasonic -
ECG
2 47k
AXIAL RES 47K OHM
CARBON FILM 1/4W
5%
R17A, R17B P47KBACT-ND Panasonic -
ECG
2 9.1k
AXIAL RES 9.1K OHM
CARBON FILM 1/4W
5%
R18A, R18B P9.1KBACT-ND Panasonic -
ECG
2 4.7 Ohms
AXIAL RES 4.7 OHM
CARBON FILM 1/4W
5%
R20A, R20B P4.7BACT-ND Panasonic -
ECG
4 10 Ohms
AXIAL RES METAL
FILM 10.0 OHM 1/2W
1%
R21A, R21B, R28A,
R28B PPC10.0XCT-ND Vishay/BC
Components
4 20R
AXIAL RES METAL
FILM 20.0 OHM 1/2W
1%
R24A, R24B, R25A,
R25B PPC20.0XCT-ND Vishay/BC
Components
2 open
AXIAL RES METAL
FILM 10.0 OHM 1/2W
1%
R29A, R29B PPC10.0XCT-ND Vishay/BC
Components
2 2.2k 1W
AXIAL RES 10 OHM 1W
5% METAL OXIDE R30A, R30B 10W-1-ND Yageo
2 2.2k 1W
AXIAL RES 2.2K OHM
1W 5% METAL OXIDE R31A, R31B 2.2KW-1-ND Yageo
1 715 1%
AXIAL RES 715 OHM
1% 50PPM 1/4W R103 CMF715QFCT-ND Vishay/Dale
www.irf.com Page 35 of 41
IRAUDAMP7D REV 2.9
1 100k
RES 100K OHM
CARBON FILM 1/4W
5%
R109 P100KBACT-ND
Panasonic -
ECG
1 47k
AXIAL RES 47K OHM
CARBON FILM 1/4W
5%
R112 P47KBACT-ND
Panasonic -
ECG
2 1k 1W
AXIAL RES 1.0K OHM
1W 5% METAL OXIDE R114A, R114B 1.0KW-1-ND Yageo
2 15k
AXIAL RES 15k OHM
CARBON FILM 1/4W
5%
R115A, R115B P15KBACT-ND Panasonic -
ECG
4 3.3k 1W
AXIAL RES 3.3K OHM
1W 5% METAL OXIDE
R117A, R117B,
R118A, R118B 3.3KW-1-ND Yageo
2 22k
AXIAL RES 22K OHM
CARBON FILM 1/4W
5%
R300, R301 P22KBACT-ND Panasonic -
ECG
2 100 Ohms
AXIAL RES 100 OHM
CARBON FILM 1/4W
5%
R302, R303 P100BACT-ND Panasonic -
ECG
1 RCJ-013
(White CH2)
CONN RCA JACK
METAL R/A WHT PCB RCA1A CP-1402-ND
(White) CUI Inc
1 RCJ-012 (Red
CH1)
CONN RCA JACK
METAL R/A WHT PCB RCA1B CP-1401-ND (Red) CUI Inc
2 EG2209A
SWITCH SLIDE DPDT
12V .1A L=4 S1, S300 EG1908-ND E-Switch
2 ED365/2
TERMINAL BLOCK
7.50MM 2POS PCB SPKR1A, SPKR1B ED2354-ND On Shore
Technology
1 2.2k at 25C THERMISTOR NTC
2.2K OHM LEADED TH100 BC2304-ND
Vishay/BC
Components
2 IRS2092PbF
Class D Controller,
IRS2092PbF DIP-16,
Class D Controller,
IRS2092PbFDIP-16
U1A, U1B IR's P/N International
Rectifier
1 TL071CP
IC LN JFET-IN GP OP
AMP 8-DIP U300 296-7186-5-ND
Texas
Instruments
4 15V
DIODE Zener 500MW
15V DO35
Z1A, Z1B, Z102A,
Z102B
1N5245B-TPCT-
ND
Micro
Commercial
Co.
1 68V
DIODE Zener 500MW
68V DO35 Z100 1N5266B-TPCT-
ND
Micro
Commercial
Co.
1 39V
DIODE Zener 500MW
39V DO35 Z101 1N5259BDICT-ND
Micro
Commercial
Co.
4 5.6V
DIODE Zener 500MW
5.6V DO35
Z103A, Z103B,
Z104A, Z104B
1N5232B-TPCT-
ND
Micro
Commercial
Co.
Note all ½ W and 1W resistors are flame proof part numbers
Table 4 IRAUDAMP7D Mechanical Bill of Materials
Quantit
y Value Description Designator Digikey
P/N Vendor
1 16-DIP Socket
16 PIN SOLDER TAIL DIP
SOCKET IC Socket 1 A402AE
-ND
Aries
Electro-
nics
5 Washer #4 SS WASHER LOCK
INTERNAL #4 SS
Lock washer 1, Lock washer 2,
Lock washer 3, Lock washer 4,
Lock washer 5
H729-
ND
Building
Fasteners
1 PCB
Print Circuit Board
IRAUDAMP7D_Rev
2.2 .PCB
PCB 1 Custom
12 Screw 4-
40X5/16
SCREW MACHINE
PHILLIPS 4-40X5/16
Screw 1, Screw 2, Screw 3,
Screw 4, Screw 5, Screw 6,
Screw 7, Screw 8, Screw 9,
Screw 10, Screw 11, Screw 12
H343-
ND
Building
Fasteners
www.irf.com Page 36 of 41
IRAUDAMP7D REV 2.9
4 Stand off 0.5" STANDOFF HEX 4-
40THR .500"L ALUM
Stand Off 1, Stand Off 2, Stand
Off 3, Stand Off 4
1893K-
ND
Keystone
Electro-
nics
1 Stand off 0.5"
STANDOFF HEX M/F 4-
40 .500" ALUM, Chassis
GND
Stand Off 5 8401K-
ND
Keystone
Electro-
nics
1 AAVID 4880G Thermalloy TO-220
mounting kit with screw TO-220 mounting kit 1
Newuar
k
82K609
6
Therm-
alloy
Table 5 IRAUDAMP7D Models Differential Table
Model Name
Item AMP7D-55 AMP7D-100 AMP7D-150 AMP7D-200 Notes
IR Power
MOSFETS FET1 IRFI4024H-117P IRFI4212H-117P IRFI4019H-117P IRFI4020H-
117P
8 Ω 25 W x 2 60 W x 2 125 W x 2 250 W x 2 Stereo
Half Bridge
Output 4 Ω 50 W x 2 120 W x 2 250 W x 2 N/A Stereo
Full Bridge
Output 8 Ω 100 W x 1 240 W x 1 500 W x 1 N/A Bridged
+B, -B ±25 V ±35 V ±50 V ±70 V
Power
Supply ±B Voltage
Range
±3 V
±5 V
±8 V
±10 V
Audio Gain Gain 20 30 36 40
Feedback R8A,R8B 68k 100k 120k 130 k
+VAA R117A*
R117B* 1 k, 1 W 2.2 k, 1 W 3.3 k, 1 W 5.1 k, 1 W
-VSS R118A*
R118B* 1 k, 1 W 2.2 k, 1 W 3.3 k, 1 W 5.1 k, 1 W
R114A*
R114B* 100,1 W 220, 1 W 1 k, 1 W 2.2 k 1 W
VCC R115A
R115B 4.7 k 10 k 15 k 20 k
OCSET R12A
R12B
1.3 k
(20 A)
3.9 k
(23 A)
7.5 k
(30 A)
5.1 k
(23 A)
(Trip
level)
CSH R18A
R18B
0.0
(20A)
4.7 k
(23A)
9.1 k
(29A)
8.2 k
(23 A)
(Trip
level)
Oscillation
Frequency
R11A
R11B 270 270 300 360 400kHz
VB R17A
R17B 20 k 33 k 47 k 75k
OVP Z100
24 V
1N5252BDICT-
ND
47 V
1N5261BDICT-
ND
68 V
1N5266B-TPCT-
ND
91 V
1N5270B-
TPCT-ND
Zener
Digikey
P/N
UVP Z101
12 V
1N5242B-TPCT-
ND
30 V
1N5256BDICT-
ND
39 V
1N5259BDICT-
ND
51 V
1N5262B-
TPCT-ND
Zener
Digikey
P/N
Clamping
Diode
D5A
D5B
D6A
D6B
IN4002 IN4002 IN4002 N/A
* Marked components are axial, ±5 %, ¼ w, and flame proof type.
www.irf.com Page 37 of 41
IRAUDAMP7D REV 2.9
IRAUDAMP7D Hardware
Screw
Lock washers
H729-ND
Dual FET
TO-220-5
PCB
Lock washer
Screws
H343-ND
Heatsink threaded
Heatsink threaded
Heat sink
Screw
Lock washer
Put silicone grease between
the heat spreader and TO-220-5
Flat Washer #4
Fig 37 Dual MOSFET Mounting
Screw
Lock washer
PCB
Screw
TO-220 Pad insulator
Lock washer
Heatsink threaded
Heatsink threaded
Heat Sink
Screws
H343-ND
TO-220
Flat Washer #4
Shoulder Washer
Lock washers
H729-ND
Fig 38 +VCC Regulator TO-220 Mounting
www.irf.com Page 38 of 41
IRAUDAMP7D REV 2.9
Fig 39 Heat Spreader
.
Screw
Screw
H343-ND
Screws
H343-ND
Stand Off 3
1893K-ND
Stand Off 5
8401K-ND
Screw
Stand Off 4
1893K-ND
Lock washers
H729-ND
Lock washer
Lock washer incert thermistor
into this hole and
put silicone grease
Stand Off 1
1893K-ND
Stand Off 2
1893K-ND
Lock washer
Screw
H343-ND
Lock washer
Screw
H343-ND
Lock washer
GND Standoff
Screw
H343-ND
Lock washer
Fig 40 Hardware Assemblies
www.irf.com Page 39 of 41
IRAUDAMP7D REV 2.9
IRAUDAMP7D PCB Specifications
PCB:
1. Single 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. Top 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.
Gerber Files Apertures Description:
All Gerber files stored in the attached CD-ROM were generated from Protel Altium
Designer Altium Designer 6. Each file name extension means the following:
1. .gbl Bottom copper, bottom side
2. .gto Top silk screen
3. .gbs Bottom Solder Mask
4. .gko Keep Out,
5. .gm1 Mechanical
6. .gd1 Drill Drawing
7. .gg1 Drill locations
8. .txt CNC data
9. .apr Apertures data
Additional files for assembly that may not be related with Gerber files:
10. .pcb PCB file
11. .bom Bill of materials
12. .cpl Components locations
13. .sch Schematic
14. .csv Pick and Place Components
15. .net Net List
16. .bak Back up files
17. .lib PCB libraries
www.irf.com Page 40 of 41
IRAUDAMP7D REV 2.9
Fig 41 IRAUDAMP7D PCB Top Overlay (Top View)
Fig 42 IRAUDAMP7D PCB Bottom Layer (Top View)
www.irf.com Page 41 of 41
IRAUDAMP7D REV 2.9
Revision changes descriptions
Revision Changes description Date
Rev 2.8 Released September, 03 2008
Rev 2.9 BOM append R21B;
Schematic: CH2 R21AR21B
October,24,2013
WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245 Tel: (310) 252-7105
Data and specifications subject to change without notice. 09/03/2008
