IRAUDPS1 [INFINEON]
12V System Scalable 250W to1000W Audio Power Supply;
| 型号： | IRAUDPS1 |
| 厂家： | 
Infineon |
| 描述： | 12V System Scalable 250W to1000W Audio Power Supply |
| 文件： | 总35页 (文件大小：1027K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
- 1 -
IRAUDPS1
12V System Scalable 250W to1000W Audio Power Supply
For Class D Audio Power Amplifiers
Using the IR2085 self oscillating gate driver
And Direct FETS IRF6648
By
Manuel Rodríguez
CAUTION:
International Rectifier suggests the following guidelines for safe operation and handling of
IRAUDPS1 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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Page 1 of 35
IRAUDPS1
- 2 -
Page
Item
1
Table of Contents
Introduction
3
2
System Specifications
4
3
Functional Block Description
IRAUDPS1 Block Diagram
Schematic IR2085 module
IRAUDPS1 mother board schematic
IR2085 module PCB layout
IRAUDPS1 mother PCB layout
BOM of IR2085 module
BOM of IRAUDPS1 mother board
BOM of Mechanical parts
Scalable IRAUDPS1 power table
Performance and test procedure
IRAUDPS1 Fabrication Drawings
Transformer winding instructions
Design example
5
4
6
5
7
6
8
7
9
8
10-11
12
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
25
13-14
14
14
15-21
22-24
25-27
28
Transformer design
28-30
30
MOSFET selection
Switching losses
31
Efficiency calculations
32
Frequency of oscillation
Selecting dead time
33
33
Over Temperature Protection
Short circuit protection
33
33
BJT gate driver option
33
Music Load
34
Revision Changes Descriptions
35
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Page 2 of 35
IRAUDPS1
- 3 -
Introduction
The IRAUDPS1 reference design is a 12 volts systems Audio Power Supply for automotive applications
designed to provide voltage rails (+B and –B) for Class D audio power amplifiers
This reference design demonstrates how to use the IR2085 as PWM and gate driver for a Push-Pull DC to
DC converter, along with IR’s Direct FETS IRF6648
The resulting design uses a compact design with the Direct FETS and provides all the required protections.
NOTE: The IRAUDPS1 is an scalable power output design, and unless otherwise noted,
this user’s manual and the reference design board is the 500W
Table 1 IRAUDPS1 scalable table
IRAUDPS1
250W
500W
1000W
Nominal
Voltage
output
Nominal
Output
+B, -B
+B, -B
±35V
±35V
±35V
3.5A
7A
14A
Current
Stereo System
100W x 2
8 channel System
100W x 4
8 channel System
100W x 8
Application
IR Class D Model
IRAUDAMP7D
IRAUDAMP8
IRAUDAMP8 x 2
Detailed output power versions that can be configured by replacing components given in
the component selection of Table 7 on page 14
.
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Page 3 of 35
IRAUDPS1
- 4 -
System Specification
All specs and tests are based on a 14.4V battery voltage supplying an International Rectifier Class
D reference design with all channels driven at 1 kHz and a resistive load.
Table 2
Specification
IR Class D Load
Input current with no load
ACC Remote ON Level
ACC input impedance
Turn ON delay
250W
IRAUDAMP5
0.35A +/- 10%
4.5-6V
10k+/- 10%
1-1.5 Sec
30A Max
250W
18A
3.5A
+/- 35V +/-10%
+/- 10%
IRAUDPS1
IRAUAMP8
0.35A +/- 10%
4.5-6V
10k+/- 10%
1-1.5 Sec
30A Max
500W
35.5A
7A
+/- 35V +/-10%
+/- 10%
1000W
IRAUAMP8 x 2
0.35A +/- 10%
4.5-6V
10k+/- 10%
1-1.5 Sec
30A Max
1000W
71A
14A
+/- 35V +/-10%
+/- 15%
In-Rush Current
Output power full loaded
Input current full loaded
Output Current per supply
Output voltage
Regulation
Ripple outputs, laded at
400W audio 1khz
1.5V P.P.
1.8V P.P.
2V P.P.
Efficiency at ½ and full of
rated power
Isolation between Battery
and Outputs Gnd
Battery OVP
90-85%
1k Ohm
92-87%
1k Ohm
90-80%
1k Ohm
18-18.5V
8.0-8.5V
10A
18-18.5V
8.0-8.5V
20A
18-18.5V
8.0-8.5V
40A
Battery UVP
Output SCP
Outputs OVP
40-45V
40-45V
40-45V
Over temperature
protection (OTP)
OTP hysteresis
Led Indicators
Size
90C +/- 5C
90C +/- 5C
90C +/- 5C
10C
10C
10C
Red LED= SCP, Blue LED= OK
3” W x 5.3” L x 1.5” H
Table 3
+B, -B Voltage outputs vs. Battery voltage all models
Voltage outputs at 16.0V battery input with
no signal input at class D
+/- 39.5V +/- 10%
Voltage outputs at 12.0V
+/- 28V +/- 10%
Voltage outputs at 8.0V battery input with
no signal input at class D
+/- 19.2V +/- 10%
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Page 4 of 35
IRAUDPS1
- 5 -
Functional Block Description
Fig 1 below shows the functional block diagram which basically is an isolated DC-DC converter
with a step-up push-pull transformer from a 12V system that converts it to +/- 35V using the
IR2085 as a PWM and gate driver along with the Direct FETS IRF6648.
The IR2085 Module contains all the housekeeping circuitry to protect the IRAUDPS1 against
streamer conditions which are:
1. Soft start circuit in order to control the inrush-current at the moment the IRAUDPS1 power
is turned ON
2. Short Circuit protection at outputs (SCP), which will shut down the IR2085 and remain in
latch mode until the Remote ON /OFF switch is released
3. 12V system Over Voltage protection (OVP1). if Battery input voltage is greater than 18V..
this could happen when the vehicle’s battery is disconnected or a vehicle’s alternator fails.
4. Over voltage Output (OVP2) is greater than +/-45V at +B terminal if battery input is greater
than 16V
5. Over Temperature Protection (OTP), resistor Thermistor senses the chassis temperatures
from Direct FETS
Fig 2 is the complete schematic for the IR2085 Module
Fig 3 is the complete schematic for the IRAUDPS1 with all scalable components required
Figs 4 to Fig 10 are the respective PCB layouts for the IR2085 Module and the IRAUDPS1
motherboard
Tables 4 to Table 6 are the respective bills of materials
Table 7 is the IRAUDPS1 detailed output power versions that can be configured by replacing
components
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Page 5 of 35
IRAUDPS1
- 6 -
IRAUDPS1 Block Diagram
PUSH PULL
+Current
Sense
+B Supply
Rectifiers
& filters
FUSES
+BATT.
GND
+B
SGnd
-B
Battery
terminal
inputs
+14.4V
EMI
Filter
-B Supply
Rectifiers
& filters
Chassis GND
-Current
Sense
OVP1
IR2085
SD
+Batt, OVP
Soft Start
Batt Gnd
SGnd
SCP
OTP
ON
Rem ON/OFF
and +12V
Regulator
Remote
ON/OFF
Rem
Thermistor
Thermally connected to heat spreader
+B, OVP
OVP2
IR2085 Module
Fig 1 Functional Block Diagram
.
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Page 6 of 35
IRAUDPS1
- 7 -
10V
V1
R31
470
Red
2
1
1
2
2
1
4.7k
R22
Turn_ON
1
2
1
4
2
Turn_ON
SCP+
DZ4
Q7
LED1
V1
3
2
OVP2
OTP
1k
R28
U1B
6
1
2
TH1
1
2
7
LM393
10k
R6
R17
10k
5
6
5
1
2
D1
1Meg
R4
1
1
2
J6
SCP-
V1
10k
1
1
2
2
SCP+
3
2
1
0.1uF
R23
10k
SCP
2
1
V1
SCP
SCP-
Soft Start
C7
U1A
R24
3
2
1
1
12
J2
LM393
22
R18
14.4V
14.4V
2
2
1
2
1
D2
D7
C6
1
Header 2
0.1uF
V1
OVP
2
OVP2
J3
0.01uF
0.0
22
2
1
2
1
2
1
2
1
IR2085
R27
R19
C1
R2
CS
VCC
2
1
1
2
3
4
8
7
6
5
Header 2
CS
OSC
GND
LO
VB1
1k
open
HO1
U2
VS2 J4
C2:
C2
4
47pF=80nS
1
2
14.4V
VS1
14.4V
3
2
1
100pF=110nS
220pF=130nS
470pF=170nS
1nF1=200ns
470pF
VS1
VCC
LO1
VCC
J5
0.0
22
R20
R1@C2_470pF:
15k=100khz
2
1
2
2
1
1
2
1
R30
30k=50khz
Q2
Turn_ON
R11
VCC
CP2
VCC
1
1nF,15k=50kHz
2
1
1
2
Header 2
R25
4.7k
2
1
2.2R
open
10uF
Q1
DZ3
1k
R26
BluLeED2
3
14
2
1
2
2
14.4V
C8
J1
22
1
2
12V
10k
R9
6
5
4
3
2
1
2
0.1uF
R21
Remote ON
Remote ON
5
6
1
TH1
1
Header 6H
Drawing by: M.Rodriguez
e-mail: mrodrig5@irf.com
2085_Control Module_R3
Fig 2 schematic of IR2085 Module
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Page 7 of 35
IRAUDPS1
- 8 -
.
.
`
IRAUDPS1, 12V System SMPS, 500W Converter with Direct Fets
And IR2085 PWM Module
Optional
(open) MUR1620CTG
1
J6
+B
SW2
VS2
2
3
2
1
CR1
+V_Rectified
3
SCP+
SCP-
SW1
(open) MUR1620CTRG
3
Header 3
J3
Transformer:
Core: Magnetics P/NZR42915TC
P1,P2=4T#18x4,60uH,DCR3mOhms
S1,S2=10T#20x3=470uH,DCR46mOhms
LO1A
SW1
SW2
D_FET2
open
D_FET6
IRF6648
D_FET10
open
D_FET14
IRF6648
2
1
1
1
1
1
1
CR2
1
-V_Rectified
2
1
2.2K
R14
2.2K
R31
Header 2
2
2
10k
R51
1
2
TR1
8
1
2
SCP+
+CS
J2
LO1B
6.2
Q1
+V
10k
R50
1
2
2
1
SW1
1
+V_Rectified
MMBT5401
2.2nF/100V
P1
S1
2
1
2
2
1
R70
R44
L1
Header 2
2
3.3uH/10A
6.2
R73
D1
D4
C34
Z2
C26
1
3
1
3
+B
2
R47
L6
L5
+Battery
Fuse1
14.4V
14.4V
7
6
1
1
1
2
2
FB1
FB2
1
1
1
2 F1
2 F2
2 F3
C28
2
0.03R
R49
2
1
3
2
1
15A
C7
C8
C9
1uF
SMAZ39-TP
0.1uF/250V
Fuse2
J4
1uF
1uF
3
1
3
1
4
3
2
1
VS2
VS1
0.03R
Z1
2
2
S2
15A
14.4V
D2
D3
C29
S2
TB2
TB1
2
1
C21
1
2
C23
2
6.2
Fuse3
2
2
1
1
1
TB4
SMAZ39-TP
2.2nF/100V
0.1uF/250V
+V
2
1
3
R72
6.2
1uF/100V
C24
C22
Header 4
4
5
15A
SGnd
-V
C3
2
1
1
2
VS1
ZP42915TC
SW2
1
2
L2
R71
C33
1uF
1uF/100V
-V_Rectified
C35
+B
1
2
R54
J5
LO2A
1
2
2
R60
D_FET4
open
D_FET8
IRF6648
D_FET12
open
D_FET16
IRF6648
C25
1uF/100V
1
1
1
1
1
1
1
2
12
2
2
1
1
2
+B
0.03R
R48
22k
R55
Manual ON/OFF
0.1uF
2.2K
R32
2.2K
R16
14.4V
Header 2
2
2
LED1
LED2
1
2
3PSW
-B
R45
TB3
3
1
1
1
2
1
2
0.03R
R53
2
2.2k
R61
1
2
1
off
1k
S1
C27
J1
LO2B
2
Remote ON/OFF
-B
1
6
5
4
3
2
1
22k
R56
GND
SGnd
10k
-B
2
R52
2
-V
-CS
C30
1
2.2k
SCP-
1
1
2
2
10k
TH1,thermallyconnectedtoheat-spreader
0.01uF
C32
Chassis GND
0.01uF
SGnd
Drawing by: M.Rodriguez Mrodrig5@irf.com
Fig 3 IRAUPS1 Mother Board Schematic
.
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Page 8 of 35
IRAUDPS1
- 9 -
Fig 4 IR2085 Module Top silk screen layout
.
Fig 6 IR2085 Module Top side layout
Fig 5 IR2085 Module bottom side layout
.
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Page 9 of 35
IRAUDPS1
10 -
.
Fig 7 IRAUDPS1 Mother Board Top silk screen layout
.
Fig 8 IRAUDPS1 Mother Board Top copper
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Page 10 of 35
IRAUDPS1
11 -
.
Fig 9 IRAUDPS1 Mother Board Bottom silk screen layout
.
.
Fig 10 IRAUDPS1 Mother Board Bottom layout
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Page 11 of 35
IRAUDPS1
12 -
Bill of Materials
Table 4
IRS2085 Module
Quantity
Value
Description
Designator
Digikey P/N
PCC1784CT-ND
Vendor
Panasonic - ECG
Murata
3
1
1
3
2
7
1
1
1
1
1
1
1
2
1
2
2
1
1
0.01uF
470pF
100pF
0.1uF
10uF
CAP 10000PF 50V CERM X7R 0603
CAP CER 470PF 50V 5% C0G 0603
CAP CERAMIC 100PF 50V NP0 0603
C1, C4, C5
C2
C3
490-1443-1-ND
311-1069-1-ND
Yageo
CAP CERM .10UF 50V 20% 0805 SMD
CAP TANTALUM 10UF 16V 10% SMD
DIODE SWITCH 100V 150MW SOD-523
SOD123_Z
C6, C7, C8
CP1, CP2
478-3351-1-ND
AVX Corporation
Kemet
495-2236-1-ND
1N4148WT-7
18V
D1, D2, D3, D4, D5, D6, D7
1N4148WTDICT-ND
MMSZ5248BS-FDICT-ND
UDZSTE-175.6BCT-ND
BZT52C12S-TPMSCT-ND
MMSZ5240BSDICT-ND
929500E-01-01-ND
160-1422-1-ND
Diodes Inc
Diodes Inc
Rohm
DZ1
5.6V
DIODE ZENER 5.6V 200MW SOD-323
DIODE ZENER 200MW 12V SOD323
DIODE ZENER 10V 200MW SOD-323
Header, 6-Pin, Right Angle
DZ2
12V
DZ3
Micro Commercia
Diodes Inc
3M
10V
DZ4
Header
Red
J1,J2,J3,J4,J5.J6
LED1
LED RED ORAN CLEAR THIN 0805 SMD
LED 468NM BLUE CLEAR 0805 SMD
Lite-On Inc
Lite-On Inc
Panasonic - SSG
NXP
Blue
LED2
160-1645-1-ND
XN04311
PBSS305NX
open
TRANS ARRAY PNP/NPN W/RES MINI6P Q1, Q7
XN0431100LCT-ND
568-4177-1-ND
TRANS NPN 80V 4.6A SOT-89
Q2
(OPEN) TRANS NPN 80V 4.6A SOT-89
(OPEN) TRANS PNP 80V 4A SOT-89
RES 30K OHM 1/10W 5% 0603 SMD
RES 1K OHM 1/10W 5% 0603 SMD
Q3, Q4
Q5, Q6
R1
568-4177-1-ND
NXP
open
568-4178-1-ND
NXP
30K
RHM30KGCT-ND
RHM1.0KGCT-ND
Rohm
1k
R2
Rohm
R3,R6,R9,R14, R15, R16, R17, R23, R24,
R32,R33
11
1
4
1
1
4
2
2
1
1
1
1
10k
RES 10K OHM 1/10W 5% 0603 SMD
RES 1.0M OHM 1/10W 5% 0603 SMD
RES 4.7K OHM 1/10W 5% 0603 SMD
RES 470K OHM 1/10W 5% 0603 SMD
RES 2.2 OHM 1/4W 1% 1206 SMD
RES 22 OHM 1/8W 5% 0805 SMD
RES 1.0K OHM 1/10W 5% 0603 SMD
RES 0.0 OHM 1/8W 5% 0805 SMD
RES 47K OHM 1/10W 5% 0603 SMD
RES 470 OHM 1/8W 5% 0805 SMD
IC COMP DUAL OFFSET LV 8SOIC
Controller and Gate Driver
RHM10KGCT-ND
311-1.0MGRCT-ND
RHM4.7KGCT-ND
RHM470KGCT-ND
P2.2RCT-ND
Rohm
1Meg
4.7k
R4
Yageo
R8, R13, R22, R25
Rohm
470k
2.2
R10
Rohm
R11
Panasonic - ECG
Rohm
22
R18, R19, R20, R21
RHM22ARCT-ND
RHM1.0KGCT-ND
RHM0.0ARCT-ND
RHM47KGCT-ND
RHM470ARCT-ND
LM393DR2GOSCT-ND
IR2085
1k
R26, R28
R27, R30
R29
Rohm
0.0
Rohm
47k
Rohm
470
R31
Rohm
LM393DR2G
IR2085
U1
ON Semi
International Rect
U2
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Page 12 of 35
IRAUDPS1
13 -
Table 5
IRAUDPS1 Mother Board Bill of Materials
Quantity
Value
Description
Designator
Digikey P/N
490-3908-1-ND
478-1505-1-ND
478-1519-1-ND
490-3909-1-ND
PCC1784CT-ND
399-4674-1-ND
493-1842-ND
Vendor
Murata Electronics North
AVX Corporation
AVX Corporation
Murata Electronics
Panasonic - ECG
Kemet
4
1
3
4
4
3
3
4
1
1
4
4
4
3
2
3
1
2
1
1
1
1
4
1
1
1
4
4
2
2
4
1uF/50V
CAP CER 1UF 50V X7R 1206
C3, C7, C8, C9
C21
1000pF/200V
2.2nF/100V
1uF/100V
0.01uF
CAP CER 1000PF 10% 200V X7R 1206
CAP CER 2200PF 10% 100V X7R 1206
CAP CER 1UF 100V X7R 1206
C22, C33, C34
C23, C24, C31, C35
C26, C27, C30, C32
C28, C29,C25
CP3, CP4, CP5
CAP 10000PF 50V CERM X7R 0603
CAP CERAMIC .1UF 250V X7R 1206
CAP 3300UF 25V ELECT PW RADIAL
CAP 1200UF 63V ELECT PW RADIAL
DIODE Comm Cathode ULT FAST 16A 200V TO220
DIODE Comm Anode ULT FAST 16A 200V TO220
DIODE FAST 200V 10A D-PAK
0.1uF/250V
3300uF/25V
1200uF/63V
(open)
Nichicon
CP10, CP11, CP12, CP13
493-1958-ND
Nichicon
CR1
MUR1620CTGOS-ND
MUR1620CTRGOS-ND
497-3536-5-ND
ON Semiconductor
ON Semiconductor
STMicroelectronics
(open)
CR2
STTH1002CB
open
D1, D2, D3, D4
FET2, FET4,FET10,FET12
FET6, FET8, FET14,FET16
F1, F2, F3
Direct-FET MOSFET N-CH 60V 86A
Direct-FET MOSFET N-CH 60V 86A
FUSEHOLDR MINI VERT PCB MNT SNGL
FERRITE 3 LINE 10A 342 OHMS
FUSE BLADE 15A/32V MINI FAST-ACT
Control Module
IRF6648TR1PBFCT-ND International Rectifier
IRF6648TR1PBFCT-ND International Rectifier
IRF6648
Fuse Holder
FERRITE QUAD LINE 10A
15A
F065-ND
Littelfuse Inc
Stwart
FB1, FB2
240-2494-ND
Fuse1, Fuse2, Fuse3
J1,J2, J3, J4,J5,J6
L1, L2
F992-ND
Littelfuse Inc
IR Module_2085_R2 PCB
Coiltronics
Module_2085_R2
3.3uH/10A
Blue
Custom
INDUCTOR POWER 3.31UH 11.4A T/H
LED 468NM BLUE CLEAR 0805 SMD
LED 468NM BLUE CLEAR 0805 SMD
TRANSISTOR PNP 150V SOT-23
TRANSISTOR NPN 160V SOT-23
RES 2.2K OHM 1/8W 5% 0805 SMD
RES 100 OHM 1/4W 5% 1206 SMD
RES 10 OHM 1/4W 5% 1206 SMD
RES 1.0K OHM 1/4W 5% 1206 SMD
RES .03 OHM 1W 1% 2512 SMD
RES 10K OHM 1/10W 5% 0603 SMD
RES 2.2K OHM 1W 5% 2512 SMD
RES 22K OHM 1/4W 5% 1206 SMD
RES 6.2 OHM 1/4W 5% 1206 SMD
513-1522-ND
LED1
160-1645-1-ND
160-1645-1-ND
MMBT5401FSCT-ND
MMBT5551FSCT-ND
'RHM2.2KARCT-ND
311-100ERCT-ND
RHM10ERCT-ND
RHM1.0KERCT-ND
WSLG-.03CT-ND
RHM10KGCT-ND
PT2.2KXCT-ND
RHM22KERCT-ND
RHM6.2ERCT-ND
Lite-On Inc
Lite-On Inc
Fairchild Semiconductor
Fairchild Semiconductor
Rohm
Blue
LED2
MMBT5401
MMBT5551
2.2K
Q1
Q2
R14, R16, R31, R32
R43
100R
Yageo
10
R44
Rohm
1k
R45
Rohm
0.03R
R47, R48, R49, R54
R50, R51, R52, R53
R55, R56
Vishay/Dale
Rohm
10k
2.2k
Panasonic - ECG
Rohm
22k
R60, R61
6.2
R70, R71, R72, R73
Rohm
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Page 13 of 35
IRAUDPS1
14 -
1
2
1
1
1
1
2
Toggle SW 3Pos
Gold terminal block
TB 2 terminals
1714984
Toggle SW 3Pos
S1
EG2377-ND
E-Switch
Gold terminal Block #8 AWG
CONN TERM BLOCK 2POS 5MM PCB
CONN TERM BLOCK 3POS 9.52MM PCB
THERMISTOR 100K OHM NTC 0805 SMD
Power Transformer
TB1, TB2
TB3
070-850
Audio Express
Phoenix Contact
Phoenix Contact
Murata Electronics
Magnetics
277-1022-ND
TB4
277-1272-ND
100K
TH1
490-2451-1-ND
Custom TR500-2085
SMAZ39-TPMSCT-ND
ZP42915TC
SMAZ39-TP
TR1
DIODE ZENER 1W 39V SMA
Z1, Z2
Micro Commercial Co
.
Table 6
Mechanical BOM
Quantity
Description
Value
Digikey P/N
Vendor
1
1
1
1
2
4
6
6
Aluminum Bar heat spreader R2
Aluminum Base heat sink R2
Aluminum Bar 2085
Aluminum Bar 2085
PCB
Custom
China
Custom 2085
China
Print Circuit Board IR2085_MB_R2 .PCB
THERMAL PAD .080" 4X4" GAPPAD
(Optional) THERMAL PAD .007" W/ADH
SPACER ROUND 1" #4 SCRW .250" BR
NUT HEX 4-40 STAINLESS STEEL
SCREW MACHINE PHILLIPS 4-40X3/4
WASHER LOCK INTERNAL #4 SS
IR2085_MB_R1 PCB Assy
Ber164-ND
China
THERMAL PAD .080" 4X4" GAPPAD
(Optional) THERMAL PAD TO-220
Stand off 0.250"
Bergquist
173-7-240A
1454AK-ND
H724-ND
Wakefield
Keystone Electronics
Building Fasteners
Building Fasteners
Building Fasteners
Nut 4-40
Screw 4-40X3/4
H350-ND
12
Washer #4 SS
H729-ND
.
Table 7
Scalable IRAUDPS1 by changing the following components
Component
Notes
250W
IRAUDPS1
1000W
Power Transformer T1
Direct FETs
See winding instructions
IR P/N TR-2085-250W
IR P/N TR-2085-500W
IR P/N TR-2085-1000W
Populate the respective Direct FET D_FET6, D_FET16
by IR6648 as shown on respective
model
D_FET6,D_FET8,
D_FET16
D_FET14, D_FET6,D_FET8,
D_FET14,
D_FET10,
D_FET16
D_FET2,D_FET4,
D_FET12
R47, R48, R47, R54
Fuse F1, F2, F3
D1, D2, D3, D4
CP3, CP4, CP5
Short circuit sensitivity
Input Current
0.06R
0.03R
15A
0.015R
25A
5A
Output Rectifiers
Input Filters
4A
8A
16A
2200uF/25V
3300uF/25V
3900uF/25V
.
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Page 14 of 35
IRAUDPS1
15 -
IRAUPS1 Application and connections
Fig 11 test Setup
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Page 15 of 35
IRAUDPS1
- 16 -
Connector Description
Battery ( - )
Battery ( + )
+B output
Analog GND
-B output
TB1
TB2
Terminal Board for Negative supply source
Terminal Board for Positive supply source
TB4-1 Positive output of +B (+Bus Rail)
TB4-2 Output GND of +B and -B
TB4-3 Negative output of –B (-Bus Rail)
Switch Description
Remote-OFF-Test
Remote
This position PS1 can be turned ON remotely by vehicle’s
ACC (Accessory voltage) or vehicle’s amplifier
OFF
Test
IRAUDPS1 is always OFF regardless of ACC input
IRAUDPS1 can be turned ON manually or for test purpose
LED Indicator Description
LED1 Red
LED2 Blue
LED3 Blue
LED4 Blue
Indicate the presence of a short circuit condition on +B or -B
Indicate the presence of PWM pulses from IR2085
Indicate the presence of +B voltage
Indicate the presence of –B voltage
Power Source Requirements
The power source shall be capable of delivering 80 Amps with current limited from 1A to
80A during the test; the output voltage shall be variable from 8V to 19V during the test
Test Procedure
1. Pre-adjust the main source power supply to 14.4V and set current limit to 1A
2. Turn on the main source power supply to standby mode
3. On IRAUDPS1 (Unit Under Test) Set the Remote ON switch to OFF (center)
4. Connect an oscilloscope probe on transformer terminals TR1 pin 1
5. Do NOT Connect the Class D Amp IRAUDAMP8 (IR2093) to +B and –B yet
6. Connect the resistive load to the class D Amp
7. Set the Audio OSC to 1 kHz and output level to 0.0V
Power up:
8. Turn ON the main source power supply, the input current from the source power
supply should be 0.0mA and all LEDS should be OFF
9. Look at LED2 on the IR2085_Module, it should be OFF, then turn ON the
Remote-OFF-Test to Test switch while you observe LED2; it will light slightly
after turning ON said switch, then LED2 will come fully bright one second after
the Remote switch was turned ON (Test position)
10. In the mean time, the figure on the oscilloscope will start from narrow pulses, up
to 50% duty cycle and the oscillation frequency shall be 50kHz as shown on Fig
12 and Fig 13 below; This is the soft-start test
IRAUDPS1
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Page 16 of 35
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Fig 13, waveform from power
transformer
Fig 12, waveform from 2085 module
11. The power consumption from the source power supply shall be 0.35A maximum
typical is 0.30A and the +B and –B LEDs will turn ON as well
12. Measure the voltage on +B and –B; it will be +/-35V ±1.5V respectively; This is
the transformer’s windings turns ratio and full-wave rectifiers
UVP Test
13. Decrease the source power supply slowly until it reaches around 8 volts while
you observe LED2 or the oscilloscope. LED2 will turn OFF or oscilloscope’s
pulse will disappear at 8V ±1.5V. Typical is 8.02V
OVP1 Test
14. Increase the source power supply slowly until it reaches around 18V while you
observe LED2 or the oscilloscope. LED2 will turn OFF or the oscilloscope’s pulse
will disappear at 18V ±1.5V. Typical is 18.5V
OVP2 Test
15. Increase the source power supply slowly until it reaches around 16V while you
observe LED2 or the oscilloscope;. LED2 will begin blinking or the oscilloscope’s
pulse will decrease in duty cycle like Fig12 when +B reaches 45V ±2.5V.
Typical is 45.0V
SCP Test
16. Adjust the source power supply to 14.4V, then while IRAUPS1 is ON, apply a
short circuit between +B and AGnd with external wires, (do not make the SC on
the terminal board or it will burn said terminals) LED1 will turn ON and LED2 will
be OFF and stay OFF until the Rem-OFF-Test Switch is turned to OFF then ON
again; This is the latch of OCP
17. Repeat the last step for –B and GND
IRAUDPS1
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Page 17 of 35
- 18 -
Full Load Power Test
18. Turn OFF the IRAUDPS1 and Connect +B and –B to the Class D Amp
IRAUDAMP8 (IR2093)
19. Turn ON the IRAUDPS1, the input current from the source power supply should
be 0.85A ±0.5A; typical input current is 0.83A with the class D IRAUDAMP8
loaded with no signal input
20. Increase the current limit from the source power supply to 35A
21. Increase slowly the output level from the Audio Oscillator until the Class D amp
gets 100W RMS per channel; if resistive loads are 4 Ohms the outputs amplitude
from amplifier will be 20V RMS
22. Under these conditions the consumption current from the source power supply
shall be 36.6A maximum; this correlates to a 10% loss for each channel and a
20% loss of the IRAUDPS1; this is the power output and efficiency test
23. The output voltages from +B and –B should be +/- 30V ±2.5V
24. Monitor the transformer waveform; it should be like Fig 14 below
25. The ripple current for +B or –B should be 3V P.P. maximum as shown on Fig 15
below
Fig 15 +B and –B Ripple voltage
Fig 14 TR1 waveform loaded
OTP Test
26. Leave the class D amp running with 100W x 4 continuous power until IRAUDPS1
gets hot and trips the shut down level while the temperature on the heat sink is
monitored next to the Thermistor sensor. The temperature for shutdown will be
90C +/-5C and the time required to make OTP will be around 30 minutes when
tested at ambient temperature
27. The thermal hysteresis shall be 10C and the time to recover it shall be one
minute, the time to make shutdown again will be 10 minutes
28. Load Regulation and Efficiency are shown in Fig 16-20 below
IRAUDPS1
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Page 18 of 35
- 19 -
Typical Performance
Regulation
40
35
30
25
20
15
10
5
0
1
2
3
4
5
6
7
8
IRAUDPS1-500W Load (Amps)
Fig 16
.
Effiency of IRAUDPS1-250W
100
90
80
70
60
50
40
30
20
10
0
0
7
14
21
28
35
42
49
56
63
70
138 204 268
Watts
Fig 17
.
IRAUDPS1
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Page 19 of 35
- 20 -
Efficiency of IRAUPS1-500W
100
90
80
70
60
50
40
30
20
10
0
0
7
14 21 28 35 42 49 56 63 69 137 204 267 333 393 457 512
Watts
Fig 18
.
Efficiency of IRAUDPS1-1000W
100
90
80
70
60
50
40
30
20
10
0
0
7
14 21 28 35 42 49 56 63 69 137 267 393 512 626 732 833
Watts
Fig 19
.
IRAUDPS1
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Page 20 of 35
- 21 -
+B, -B vs. Battery voltage outputs
50
45
40
35
30
25
20
15
10
5
0
8
9
10
11
12
13
14
15
16
17
18
Battery voltage
Fig 20
.
.
IRAUDPS1
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Page 21 of 35
- 22 -
IRAUDPS1 Fabrication Drawings
Mechanical assembly
.
HEX NUT 4-40
P/N H216-ND
HEX NUT 4-40
P/N H216-ND x 6
Lock washer
Lock washer
PCB
Stand off
0.250"
P/N 1454AK-ND x 4
Lock washer
Stand off
0.250"
Thermal Pad
P/N 1454AK-ND
Lock washer
H729-ND x 12
Aluminum
Bracket
Lock washer
Screw
H350-ND x 6
Aluminum Base
Lock washer
Screw
H350-ND
Lock washer
Lock washer
Screw
H350-ND
Fig 22 Mechanical assembly
.
DirectFETS Gap
0.030"
0.032"
0.062"
Lock washer
PCB
Lock washer
Heat Spreader (Bar)
Alumimum plate (Base)
Lock washer
Lock washer
Fig 23 Direct FET thermal dissipation
.
IRAUDPS1
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Page 22 of 35
- 23 -
.
Fig 24 Aluminum base
Fig 25 Heat Spreader for DirectFETs
.
IRAUDPS1
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Page 23 of 35
- 24 -
Fig 26 Thermal Pad
.
.
Fig 27 Input Battery Terminals
IRAUDPS1
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Page 24 of 35
- 25 -
IRAUDPS1 transformer winding instructions
IR Assy P/N IR-TR500-2085-500W
Schematic
Materials required
Start
Start
Core: Magnetics material “P” ZP42915TC
P1
S1
Finish
Start
Finish
Start
P2
S2
Finish
Finish
Fig 29
Fig 28
.
Step No. 1
Winding P1:
1. Cut 30cm length of 1.0mm gage x
4 wires of magnet wire (AWG 18)
2. Start winding P1 at 0 degrees
forward or Clock wise, as shown
on Fig 30, start is the top side,
and finish is the bottom side
3. Wind 4 turns in parallel at the
same time, evenly spaced around
the core as shown on Fig 30
4. Leave 4 cm of wire at both ends,
spaced ½ inch between ends, as
shown on Fig 30
Fig No. 30
.
Step No. 2
Winding P2:
5. Cut 30cm of 1.0mm gage x 4
wires of magnet wire (AWG 18)
6. Start winding P2 starting on the
end of P1, as shown in Fig 31,
start is the top side, and finish is
the bottom side
7. Wind the 4 at the same time
between the spaces of P1 evenly
spaced around the core, in the
same direction as shown on Fig
31
8. Leave 4 cm of wire at both ends,
spaced ½ inch between ends, as
shown on Fig 31
Fig No. 31
.
IRAUDPS1
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Page 25 of 35
- 26 -
Step No. 3
Winding S1:
9. Cut 60cm of 20 AWG (0.86mm) x
3 magnet wires
10. Start winding of S1 at 90 degrees
forward respect to the start point
of P1, as shown on Fig 32, start is
the top side, and finish is the
bottom side
11. Wind 10 turns whit the three
parallel wires at the same time,
evenly spaced around the core on
same direction as shown on Fig
32
12. Leave 4 cm of wire at both ends.
Fig No. 32
.
Winding S2:
13. Cut 60cm of 20 AWG (0.86mm) x
3 magnet wires
14. Start winding of S1 at 90 the end
pf S1 forward respect to the start
point of S1, as shown on Fig 33
15. Wind 10 turns whit the three
parallel wires at the same time,
evenly spaced around the core on
same direction as shown on Fig
33
16. Leave 4 cm of wire at both ends.
Fig No. 33
.
Step No. 5
Performing “Start and Finish wires”
Mounting holes; using an IR2085_MB_R2 PCB, perform the next instruction:
17. Perform “P1 Start” to fit into Pad 1 as
shown Fig 6.
4
18. Perform “P1 finish” and “P2 Sstart” to
be fitted into pad 2 as shown on Fig
No. 34, this is the center tap of the
Primary side
19. Perform “P2 finish”, to be fitted into
mounting hole 3 as shown in fig No. 6.
20. Perform “S1 start” (top winding) to be
connected on Pad 4 as shown on Fig
34
2
3
21. Perform “S1 finish” wire (bottom
winding) to be connected at Pad 5,
this is the center tap of the secondary
side
Fig No. 34
22. Perform “S2 start (top winding) to the
IRAUDPS1
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Page 26 of 35
- 27 -
center tap on Pad 5
23. Perform “S2 finish” of (bottom
winding) to be connected to hole 6 as
shown on fig 35
24. Cut and strip magnet wires for ½
inches long to be performed as
surface mounting as shown on Fig 35
25. Thin the transformer terminals as
shown on Fig 36
26. Before mounting on PCB measure
inductance according to next Table 8
Fig 35
Fig 36
Fig. 37
.
Table 8
Transformer’s Electrical Characteristics
Inductance at P1 and P2 on terminals 1,2 and 2,4 65uH-75uH
Inductance difference between windings P1 and P2 1uH maximum
Inductance at S1 and S2 on terminals 5,7 and 7,8 470uH minimum
Inductance difference between windings S1 and S2 2uH maximum
DCR at P1 winding 1,2 and P2 winding 2,4
DCR at S1 terminals 5,6 and S2 terminals 7,8
Number of turns for P1 and P2
Number of turns for S2 and S2
Leakage Inductance, with S1 and S2 shorted
Resistance between Primary and Secondary (P and
S windings)
3.0mOhms max
46mOhms max
4 Turns 18 AWG x 4
10 Turns 20 AWG x 3
1uH max
Infinite
Resistance between any winding and core
High-Pot between primary and secondary windings
High-Pot between any winding and core
Dimensions
Infinite
500VAC
500VAC
1.4” OD x 0.80” Height
See Fig 37
Mounting
.
IRAUDPS1
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Page 27 of 35
- 28 -
Design Example
Assume the following customer specifications are required:
A 12V system automotive power supply to drive a stereo class D amplifier 300 Watts per
channel into 4 ohms, and the maximum standby power consumption of the power supply
should be 5 watts at 14V battery voltage with no load; also efficiency should be greater
than 80%, compact design size 3 inches wide, 5 ½ long and 1 ½ high
Voltages outputs required
The first step is to calculate the output voltages and the input and output currents; the
control circuits in the IRAUDPS1 are a good reference design to design the whole
control system
+B and –B are calculated as following:
AUDIO signal VRMS = Sqrt (300W X 4 Ohms) = 34.6VRMS
Thus, +B = 34.6 x 1.4142 = +50VDC and –B = -50VDC
Input Current required from Battery
Input Current Loaded = 300W x 2 = 600W
If efficiency of the Class D amp is 90% then 600 x 1.1 = 660W
If the efficiency of the power supply is 80% then 660W x 1.2 = 792W = 800W
Thus, I loaded = 800W / 14V = 57A
Output Current provided
Total output current = 660W / 50V = 13.2A
Thus +B = 13.2 / 2 = 6.6A and –B = -6.6A
Transformer Design Example
The transformer design is a trade-off between size, operating frequency, physical
windings to achieve low leakage inductance, form factor, primary turns ratio to meet
standby input current, and type of core material
Core Selection
Core must be selected as power material composite and it can be chosen from any
major manufacturers which are Magnetics Inc, TDK, Ferroxcube, Siemens or Thomson.
Each manufacturer has a number of different powder core mixes of various materials to
achieve different advantages, so in this case Magnetics Inc core ZP42915TC is selected
according the estimated size required to fit the power required
Notice on IRADUPS1 Fig 30 and Fig 31 the primary windings are 4 turns and they are
distributed equally and spaced around the core in order to provide uniform magnetic flux
density therefore low leakage inductance, so 4 turns on primary side is a good practice
for now because it fits most of the requirements mentioned above, of which the most
important factor here is size and physical windings to achieve low leakage inductance
and core material
IRAUDPS1
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Page 28 of 35
- 29 -
Primary inductance
Primary Inductance called here as Lp is 65uH that belongs to 4 turns according to
Magnetics ZP42915TC permeability data sheet
Magnetizing current
The standby current with no load depends on the magnetizing idle of the power
transformer called here as IM and it depends on the operating switching frequency
called here as Fs
Magnetizing current = IM = 5W of standby current / 14V = 0.35A
Therefore this is the transformer’s primary windings impedance current
Thus, Transformer magnetizing impedance = ZM = 14V / 0.35A = 40 ohms
Then we assume that ZM is the same impedance of XL where XL = 6.28 x Lp x Fs
Therefore switching frequency = Fs = XL / (Lp x 6.28)
Operating switching frequency calculation
Because this is a push-pull DC-DC converter, switching frequency is calculated as
follows:
Operating switching frequency = Fs = ½ (XL / (Lp x 6.28) = 1 / 2 (6.28 x 65uH) / 40 ohms
= 48.9 kHz
Therefore we will use 50 kHz
Verification of the computations:
Transformer primary windings Impedance = XL = 6.28 x 65uH x 50 kHz = 20.41 ohms
IM = ½ (V / XL) = ½ (14V / 20.41) = 0.34A
Thus, the standby current will be 0.34A at 14V = 4.9W which will meet the customer’s
specifications
Turns ratio calculations
If the primary windings are 4 turns and they are distributed equally spaced around the
core as shown on Fig 30 and Fig 31
Thus, Volts per turn ratio = 14V / 4 turns = 3.5V per turn
Turns required on secondary = 50V / 3.5V = 14 turns
Number of wires and gauge required
Primary Windings
Because the input current will be 57A, the wire’s gauge will be the biggest possible to fit
into the core with the lowest DCR possible for a maximum efficiency and lower
temperature dissipation
Assuming 5 watts DC power dissipation on the primary side, then Primary DCR
maximum required = 5W / (57)2 = 5 / 3249 = 0.0015 ohms
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Page 29 of 35
- 30 -
Wire length required is 6 inches for 4 turns in this case in particular for Magnetics Core
ZP42915TC, Then considering copper DC resistance according to gauge table 9 below
Thus, a single # 14 AWG magnet wire is required considering only the DC resistance
(DCR), but considering the skin effect of the high frequency of operation which in this
case will be 50 kHz, therefore 5 wires in parallel # 18 are required in order to minimize
the skin effect and therefore minimize the AC resistance at 50 kHz
.
Table 9
Round copper magnet wire DCR and AC/DC Resistance ratio due to skin effect
versus frequency
25kHz
50 kHz
100kHz
AWG
#
Diameter DCR per 1ft
Skin
depth
ratio
Rac /
Rdc
Skin
depth
ratio
Rac /
Rdc
Skin
depth
ratio
Rac
/
Rdc
mils
m Ω
12
14
16
18
20
22
24
26
81.6
64.7
51.3
40.7
32.3
25.6
20.3
16.1
1.59
2.52
4.02
6.39
10.1
16.2
25.7
41.0
4.56
3.61
2.87
2.27
1.80
1.48
1.13
0.90
1.45
1.30
1.10
1.05
1.00
1.00
1.00
1.00
6.43
5.09
4.04
3.20
2.54
2.02
1.60
1.27
1.85
1.54
1.25
1.15
1.05
1.00
1.00
1.00
9.10 2.55
7.21 2.00
4.54 1.40
4.54 1.40
3.6
1.25
2.85 1.10
2.26 1.04
1.79 1.00
.
Secondary Windings
Because the secondary current is only 6.6A, lets assume a power dissipation of 2W on
the secondary windings
Secondary DCR maximum rewired = 2 / (6.6) 2 = 0.045 ohms
Thus, 3 wires # 20 required from table 9
MOSFTS Selection
Because part of the customer specification has to be a compact design, the Direct FET
IRF6648 is selected due to small package, high current capability, 60VDS, low RDSON
and low Qg feature
Quantity of MOSFETS required
Since the input current at full load will be 57 amperes, and operating frequency is 50 kHz
with 50% duty cycle (10us turn ON) and according to IRF6648 data sheet the safe
operating area (Fig 12 from data sheet)
Therefore, 15A will be the adequate current to be into the SOA
Number of devices = 57A / 15A = 3.8 devices
Thus, 4 devices required per each side of the Push-Pull transformer
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Page 30 of 35
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Gate Drive Current required
The Peak Gate drive current from IRS2085 = (VCC / RGATE ) x 2 outputs = (10V/ 22 ohms)
x 2 = 0.9A
The average current required to drive each gate depends on the switching frequency
and Qg of the selected MOSFET, which in this case Qg is 50nC (nano-coulombs) from
data sheet, there are two FETS in parallel per gate drive.
Average Gate Current = IGATE = 2Qg x Fs = 2 x 50E-9 x 50kHz = 5mA
Total Average Gate Current required = 0.005A x 4 devices = 0.02A
MOFETS Power Dissipation losses
The power dissipation at DC can be calculated as following:
57A / 4 devices = 14.25A
DC Power dissipation per device = I2 x RDSON / 2
Note RDSON at 100C from Data sheet Fig 5, is divided by 2 because it is 50% duty cycle
Power dissipation per device = (14.25)2 x 7.5mOhms / 2 = 0.76W
Total power dissipation = (57)2 x ¼ 7.5 mOhms = 3249 x 1.875 = 6.091 watts
MOSFET Switching loses
The MOSFETS switching losses can be calculated as following:
Switching losses = Turn ONLOSSES + Turn OFFLOSSES + Gate Drive LOSSES
From IRF6648 data sheet T(RISE TIME) = 29nS and T(FALL TIME) = 13nS and QGD = 14nC
Losses contributed by the size of the gate series resistor
Gate drive series resistors actually slowdown the turn ON and turn OFF timing
(See Fig 2, R18-R21)
Delay losses contributed by the gate series resistor = GRES Delay = QGD / ((VCC – VML )/
RGATE )). VML is the miller effect plateau voltage of gate charge curve. It is 5.5V for
IRF6648.
GRES Delay = 14E-9 / ((10V-5.5V) / 22 ohms) = 14E-9 / 0.2A = 70nS
The delay time that caused by large gate resistor is much longer than the rise time that
defined in IRF6648 datasheet. Thus gate resistor delay time will be used to calculate
MOSFET switching losses.
Turn ONLOSSES = FOSC x ½ x (GRES Delay) x I x 2VDS = 50kHz x 0.5 x 70nS x 14.25A x 28V
= 0.7 watts per device
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Total Turn ON losses = 0.7 x 8 = 5.6W
Note: VDS is multiplied by 2 because VDS occurs twice in Push-Pull converters
Turn OFFLOSSES = FOSC x ½ (GRES Delay) x I x 2VDS = 50kHz x 0.5 x 70nS x 14.25A x 28V =
0.70 watts per device
Total Turn ON losses = 0.70 x 8 = 5.6W
Gate losses = Qg x VGATE x FOSC
Qg from IRF6648 data sheet is 36nC typical
Gate losses = 36E-9 x 10 x 50khz = 0.018W per FET
Total Gate losses = 0.018W x 8 = 0.144W
Total switching losses = 5.6 + 5.6 + 0.144 = 11.34W
Output Rectifiers Losses
+DC rectifier losses = V(DIODE) x I(OUT) = 0.7V x 6.6A = 4.62W per diode
Total Diode rectifiers for +B and –B = 4.62 x 4 = 18.48 watts
Efficiency
Total losses then will be; Transformer losses + MOSFETS losses + switching losses +
output rectifiers losses + core losses
Core losses according to material P from Magnetics-Inc data sheet is 2 watts at 50 kHz
Total transformer losses = Primary winding loses + Secondary winding losses + Core
Losses 5W +2W + 2W +2 W = 11 watts
Total MOSFET losses = RDSON losses + Switching losses = 6.09W + 11.34W = 17.43W
Overall Losses = 11W + 17.43W + 18.48W = 46.91W
Efficiency = 600 / 600+ 46.91 = 92.74% Therefore meet the efficiency specification
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Page 32 of 35
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Frequency of oscillation
From Fig 2, the frequency of oscillation is managed by R1 and C2 values and it shall be
calculated by the equation below
FOSC = 1 / R1 x C2 = 50 kHz
Thus, at 50Khz if R1 is 30k, then C2 will be 470pF, said values as shown on schematic
Fig 2 (See IR2085 data sheet for more details)
Selecting Dead-time
Dead time selection depends on the turn ON and OFF delay of the power MOSFETS
selected, in this case IRF6648 data sheet shows 16nS for turn ON delay and 28nS for
turn OFF delay, rise time 29nS and fall time 13nS,
Therefore dead time required = 16nS + 28nS + 29nS + 13nS = 86nS per phase
Because this is a push-pull then 86nS are multiplied by two giving 172nS
Thus, dead time can be programmed according to the 2085 datasheet where dead time
values are the relationship weight of C versus R.
Therefore, Fig 2 30K ohms and 470pF gives 170nS of dead time
Over-Temperature Protection (OTP)
Thermistor is selected to get 8.2 k ohms at 90OC, it can be readjusted changing R16 or
R15 and R17 for any other temperature
Over Current Protection (OCP)
From Fig3; R47, R48, R49 and R54 can be calculated at any current protection desired
by the following equation:
OCP resistor = 0.6V / OCP current
Example: If OCP desired is 20A
Then ROCP = 0.6V / 20A = 0.03 ohms
Thus, R47, R48, R49 and R54 will be 0.06 ohms each one because two of them are in
parallel
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BJT gate driver option
Notice on schematic Fig 2 and their PCB layout that it is prepared for extra BJT drivers
Q3-Q6 that in this case they are not populated, this is in case that the customer wants
more than 4 MOSFETS in parallel for large power outputs applications
Music Load
NOTE, All previous calculations were made for continuous sine wave load for the safe
and reliable design; the average currents and power dissipations actually will be 1/8 of
power for soft music, ¼ of power for heavy rock music and 3/8 of power with dead metal
music, and ½ of rated power for subwoofer amplifiers
Music load Input current calculations
RMS Input current with constant sine wave outputs at 1 kHz all channels driven:
•
•
•
•
•
•
IRMS SINE WAVE = 14V/800W = 57A
I PEAK MUSIC = 57 x 1.4142 = 80A
ISOFT MUSIC = 57A x 1/8 = 7.1A
I
ROCK MUSIC = 57 x ¼ = 14.2A
I HEAVY METAL MUSIC = 57A x 5/8 = 21.3A
I Subwoofer = 57A x ½ =28A
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Revision changes descriptions
Revision
Changes description
Released
Date
IRAUDPS1_R3
IRAUDPS1_R3.1
IRAUDPS1_R3.2
IRAUDPS1_R3.3
January 23, 2009
March 24, 2009
April 22, 2009
Feb 21, 2013
Reviewed
Tables 1, 2, 5, 7 Revised for 500W
Page 30, 50 khz with 50% duty cycle (10us
turn ON)
Page 30, number of devices 57A/15A
Page 31-32, corrected gate drive current
calculation. Corrected power dissipation
loss calculation numbers. Corrected
MOSFET switching loss calculation.
Corrected efficiency number according to
new power losses data.
Page 33, corrected typo of dead-time, ns
WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245 Tel: (310) 252-7105
Data and specifications are subject to change without notice.
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Page 35 of 35
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