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IRDC3622D
USER GUIDE FOR DUAL OUTPUT IRDC3622D EVALUATION
BOARD USING IRF6622 AND IRF6629 DIRECTFET MOSFETS
Table of Contents
Page
Description 1
Board Features 1
Connections & Operating Instructions 2
Layout 5
Schematic 10
Bill of Materials 11
Waveforms 12
Synchronization 21
Voltage & Tracking 22
MLPQ Package 24
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www.irf.com RD-0621
USER GUIDE FOR DUAL OUTPUT IRDC3622D EVALUATION
BOARD USING IRF6622 AND IRF6629 DIRECTFET MOSFETS
DESCRIPTION
This user guide contains the schematic and bill of
materials for the IRDC3622D evaluation board.
The guide describes operation and use of the
evaluation board itself. The IR3622 IC is a dual
channel synchronous buck controller, providing a
cost-effective, high performance and flexible
solution. The two channels can be configured to
either two independent outputs or current sharing
single output. The current share configuration is
ideal for high current applications.
Key features offered by the IR3622 Include
configurable dual output, output voltage tracking,
power up/down sequencing, programmable soft-
start ramp, pre-bias start-up, latched over-voltage
protection, thermal protection, accurate reference
voltage, on-board regulator, threshold sensitive
Enable input, programmable switching frequency up
600kHz, and input under-voltage lockout for proper
start-up.
An output over-current protection function and a
hiccup current limit are implemented by sensing the
voltage developed across the on-resistance of the
synchronous rectifier MOSFET for optimum cost
and performance. Detailed application information
for the IR3622 integrated circuit is available in the
IR3622 data sheet.
BOARD FEATURES
• The board is designed for two output voltages 2.5V and 1.8V up to 20A for each output.
•V
IN = +12V, (13.2V Max)
•V
O1 = +2.5V ± 3% @ 20A, VO2 = +1.8V ± 3% @ 20A
•V
o(ripple)= 50mV maximum for each output
•F
s=350kHz
• L1=990nH, L2=540nH
•C
o1=2x100uF (SP) + 2x10uF (ceramic 0805) for 2.5V output
•Co2=2x220uF (SP) + 2x10uF (ceramic 0805) for 1.8V output
• The input voltage start threshold of the converter is set about 10V using enable pin and two
external resistors (R16A1 and R16A2).
• The converter has the option to sequence with other supplies using SEQ and Track pins (R6A1,
R16A3 and R16A4). These pins are pulled high as default.
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CONNECTIONS and OPERATING INSTRUCTIONS
Input Supplies Connection:
Two supplies are required for this board, 3.3V and 12V. Both supplies should be well regulated. The 3.3V
supplies the pull-up resistor for Power Good. The Track and Seq pins are also pulled high using 3.3V. Connect
the 3.3V supply to TP1(+) and TP2(Gnd). The12V supply is the bus voltage; It also biases IR3622 IC and
should be able to source 10A current. Connect this supply either to 8-pin connector (J1A) or solder other
connectors, such as banana jacks, to the exposed pads.
Note: For correct start up the 3.3V supply needs to be powered first.
Output Load Connection:
The load can be connected to the large screw-terminals or solder other connectors, such as banana jacks to
the exposed pads.
TB4AGround of VO2 (+1.8V)
TB3AVO2 (+1.8V)
TB2AGround of VO1 (+2.5V)
TB1AVO1 (+2.5V)
Ground of VIN
J1AVIN (+12V)
TP2Ground of the 3.3V Supply
TP1+3.3V Supply
ConnectionSignal Name
Table I. Connections
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CONNECTION DIAGRAM
+
-
20A
Load
Input
Supply
(+3.3V) +
-
J1A
20A
Load
2.5V output
1.8V output
Input
Supply
(+12V)
Fig. 1: Connection diagram of the IRDC3622D evaluation board.
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Test Points
Input, output, and control signals are accessible through test points as listed in Table II.
Table II. Test Points
Output voltage and ground for the 1.8V outputVo2 (1.8V)TP15, TP16
Remote Sensing at terminal block for the 1.8V outputREM_SEN1V8TP30, TP31
Remote Sensing at terminal block for the 2.5V outputREM_SEN2V5TP28, TP29
Soft Start for 1.8V outputSS2TP36
Output voltage and ground for the 2.5V outputVo1 (2.5V)TP9, TP13, TP21,
TP22
Enable input of the 3622 ICEnableTP35
GroundGNDTP17
Power Good output for the 1.8V outputPGD_1V8TP11
Power Good output for the 2.5V outputPGD_2V5TP7
Enable input for Sequence and TrackingSEQTP33
External Synchronization signalSYNCTP32
Soft Start for 2.5V outputSS1TP37
DescriptionSignal NameTest Point
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LAYOUT
The IRDC3622D is an eight-layer board. The top and bottom layers are 2 Oz. copper and the internal layers are
1 Oz. copper. The switching MOSFETS, Inductors, 270uF input capacitors, output capacitors, and some smaller
passive components are mounted on the top side of the board. The IR3622 IC and the rest of passive
components are mounted on the bottom layer. The DirectFET technology is used for MOSFETs.
Fig. 2: Parts placement, the top layer.
Fig. 3: Parts placement, the bottom layer.
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Fig. 4: Board layout, top layer.
Fig. 5: Board layout, mid layer 1.
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Fig. 6: Board layout, mid layer 2.
Fig. 7: Board layout, mid layer 3.
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Fig. 8: Board layout, mid layer 4.
Fig. 9: Board layout, mid layer 5.
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Fig. 10: Board layout, mid layer 6.
Fig. 11: Board layout, bottom layer.
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P3V3_STBY
R18A5
11.5K
R18A6
9.1K
P3V3_STBY
C35A2
EMPTY
C36A2
EMPTY
Vref
C29A2
0.22uF
R16A3
EMPTY
1
2
R16A4
EMPTY
1
2
L2A1
No Stuff
1
2
Vsen2
Vref
R18A1
0
TB3A
1
2
3
4
5
6
Vsen2
R18A2
11.5K
TB4A
1
2
3
4
5
6
R18A3
9.1K
C10A
1uF
P3V3_STBY
PGD_P1V8PGood2
R30A1
4.99K
C24A
5.6nF
PGD_P1V8
TP11
R6A1
0
1
2
R24A
1M
C28A
47pF
C2A
10uF
C34A
0.1uF
R11A 26.
R18A
5.1K
IR3622
MLPQ
C25A
6.8nF
C35A
10uF ,6. 3V
R19A
5.1K
C22A 22pF
C16A 22pF
REMOTE SENSE
AT TERMINAL BLOCK
R10A
open
C17A
open
C6A
10uF
P1V8
R16A5
0
1
2
C8A
0.47uF ,25V
C29A
0.22uF
U1A
IR3622 MLPQ
Vsen1 22
SS2
5
Vcc
30
VcH 1 17
PGood1 29
Trac k
32
SS1
19
HDrv 2
8
GND
28
Comp1 20
VcH 2 7
Fb1 21
Vsen2
2
PGnd2
10
Comp2
4
HDrv1 16
Vp2 26
Rt 1
VcL 12
Vout3 31
OCset1 18
LDrv 1 13
PGnd1 14
Fb2
3
OCset2
6
Enable
9
LDrv 2
11
Sync 23
Vref 27
Vp1 25
P G ood2 24
pad1
33
pad2
34
pad3
35
pad4
36
pad5
37
pad6
38
pad7
39
pad8
40
pad9
41
Seq
15
SIGNAL GND JOINS GND
AT 1 POINT
C36A
10uF ,6. 3V
C24A1
1.2nF
R18A4
0.887K
R16A
10
1
2
L2A
540nH
ETQP6F0R6BFA
1
2
C30A1
open
C9A
0.22u
C27A
180pF
C13A
220uF
C7A
1uF
R9A 3.92K
R4A 3.92K
D2A
BAT54WS
A_SOD323_B
1
2
RT = 26.7K, Fs = 350KHz
C14A
1uF
Vout3
TP33
TP35
C19A
220uF
PGood2
TP30
R16A1
10K
1
2
COA1
0.1uF
C8A1
0.47uF,25V
R16A2
1.4K
1
2
TP36
TP31
TP32
TP37
C14A1
1uF
C35A1
EMPTY
C36A1
EMPTY
C13A1
EMPTY
C19A1
EMPTY
1
2
C9A1
0.22uF
Q21A
IRF6622 SQ
2
5
4
1
3
6
7
TP15
R24A1
1M
C29A1
0.22uF
Q22A
IRF6629 MX
2
5
4
1
3
6
7
TP16
Fig. 12: Schematic of the IRDC3622D board.
TP1
Q12A
IRF6629 MX
2
5
4
1
3
6
7
P2V5
TP2
TP9
TP21
TB1A
1
2
3
4
5
6
+
C80A
270uF
1
2
R15A1 0
L1A1
No Stuf f
1
2
REMOTE SENSE
AT TER MINAL BLOCK
TP22
C29A3
0.22uF
TB2A
1
2
3
4
5
6
+
C39A
270uF
1
2
L1A
990nH
ETQP6F1R1BFA
1
2
C32A
0.1uF
C3A
10uF
PGD_P2V5
C37A
10uF,6.3V
C38A
10uF ,6. 3V
COA
0.1uF
TP28
7K
R17A
3.01K
P2V5
R15A 6.49K
R21A
3.01K
TP29
P2V5
P3V3_STBY
C30A
open
R7A
open
C5A
10uF
C11A
open
R20A
0.499K
R30A
4.99K
M1A
HEATSINK MOUNT
1
C3v 3
10uF
P12VA
J1A
GND1 1
GND2 2
GND3 3
GND4 4
+12V4
8
+12V3
7
+12V2
6
+12V1
5
TH 1 9
TH 2 10
F
C15A2
EMPTY
R14A
6.49K
C26A
2.2nF
D1A
BAT54WS
A_SOD323_B
1
2
C37A2
EMPTY
PGD_P2V5
Input capacitors must
support 9.6Arms for
2.5Vo at 20 A and 1.8Vo at 20A
TP13
C37A3
EMPTY
C15A3
EMPTY
C15A1
100uF
C37A1
EMPTY
C38A1
EMPTY
TP7
D1A1
BAT54WS
A_SOD323_B
1
2
TP17
2.5V and 1.8V / 20A, 350KHz DESIGN
D2A1
BAT54WS
A_SOD323_B
C15A
100uF
Q11A
IRF6622 SQ
2
5
4
1
3
6
7
UNLESS OTHERWISE SPECIFIED:
Capacitors are 0603, 10% max, 16V min, X5R min
Resistors are 0603, 1%, 100mW
P3V3_STBY
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BILL OF MATERIALS
Item Qty Reference Value Description PCB Footprint Manufacturer Part Number
14
COA1, C32A, C34A,
COA 0.1uF 0.1uF-0603-25V-X7R-10% A_MC-0603 Panasonic ECJ1VB1E104
22
C30A, C30A1 Open A_MC-0603
35
C2A, C3A, C5A, C6A,
C3v3 10uF 10uF-1206-16V-X7R-20% A_MC-1206 Murata GRM31CR61C106KC31L
44
C7A, C10A, C14A,
C14A1 1uF 1uF-0603-16V-X7R-10% A_MC-0603 Murata GRM188R71C105KA12D
52
C8A, C8A1 0.47uF 0.47uF-0603-25V-X7R-10% A_MC-0603 Murata GRM188R71E474KA12D
66
C9A,C29A,
C9A1,C29A1,
C29A2,C29A3 0.22uF 0.22uF-0603-16V-X7R-10% A_MC-0603 Panasonic ECJ1VB1C224
72
C11A, C17A Open A_MC-0603
82
C13A, C19A 220uF 220uF-D4-2V-9mOhm-SP A_MC-6MM Panasonic EEFSX0D221R
92
C15A, C15A1 100uF 100uF-D4-4V-9mOhm-SP A_MC-6MM Panasonic EEFSX0G101R
10 2 C16A, C22A 22pF 22pF-0603-50V-X7R-10% A_MC-0603 Panasonic ECJ1VC1H220J
11 1 C24A 5.6nF 5600pF-0603-50V-X7R-10% A_MC-0603 Panasonic ECJ1VB1H562K
12 1 C25A 6.8nF 6800pF-0603-50V-X7R-10% A_MC-0603 Panasonic ECJ1VB1H682K
13 1 C26A 2.2nF 2200pF-0603-50V-X7R-10% A_MC-0603 Panasonic ECJ1VB1H222K
14 1 C27A 180pF 180pF-0603-50V-C0G-5% A_MC-0603 Panasonic ECJ1VC1H181J
15 1 C28A 47pF 47pF-0603-50V-C0G-5% A_MC-0603 AVX 06035A470JAT2A
16 4
C35A,C36A, C37A,
C38A 10uF 10uF-0805-6.3V-X5R-10% A_MC-0805 AVX 08056D106KAT2A
17 2 C39A,C80A 270uF 270uF-8mm-16V A_MC138-336D Sanyo 16SEPC270M
18 4
C13A1, C15A2, C15A3,
C19A1 Open A_MC-6MM
19 1 C24A1 1.2nF 1200pF-0603-50V-X7R-10% A_MC-0603
20 8
C35A1, C35A2, C36A1,
C36A2, C37A1, C37A2,
C37A3, C38A1 Open A_MC-0805
21 4 D1A, D2A, D1A1, D2A1 BAT54WS Schottky,SOD323,30V,0.2A A_SOD323_B International Rectifier BAT54WS
22 1 J1A ATX8PINS CONN,8 Pins,2 Rows PWR2X4 Molex 39299082
23 1 L1A 990nH A_INDUCT-320 Panasonic ETQP6F1R1BFA
24 1 L2A 540nH A_INDUCT-320 Panasonic ETQP6F0R6BFA
25 2 L1A1, L2A1 Open IR_PA0513
26 2 Q11A, Q21A IRF6622 SQ IRF6622 SQ 25V IR_DIRFET_SQ International Rectifier IRF6622
27 2 Q12A, Q22A IRF6629 MX IRF6629 MX 25V IR_DIRFET_MX International Rectifier IRF6629
28 2 R4A, R9A, 3.92K RES, 0603, 1%, 1/10W A_CR-0603 Rohm MCR03EZPFX3922
29 2 R30A, R30A1 4.99K RES, 0603, 1%, 1/10W A_CR-0603 Rohm MCR03EZPFX4991
30 2 R7A, R10A Open A_CR-0805
31 1 R11A 26.7K RES, 0603, 1%, 1/10W A_CR-0603 Rohm MCR03EZPFX4320
32 4
R6A1, R15A1, R16A5,
R18A1 0 RES, 0603, 1%, 1/10W A_CR-0603 Rohm MCR03EZPJ000
33 2 R14A, R15A 6.49K RES, 0603, 1%, 1/10W A_CR-0603 Rohm MCR03EZPFX6491
34 1 R16A 10 RES, 0603, 1%, 1/10W A_CR-0603 Panasonic ERJ-3EKF10R0V
35 2 R17A, R21A 3.01K RES, 0603, 1%, 1/10W A_CR-0603 Rohm MCR03EZPFX3011
36 2 R18A, R19A 5.1K RES, 0603, 1%, 1/10W A_CR-0603 Yageo 9C06031A5101FKHFT
37 1 R20A 0.499K RES, 0603, 1%, 1/10W A_CR-0603 Rohm MCR03EZPFX4990
38 2 R24A, R24A1 1M RES, 0603, 1%, 1/10W A_CR-0603 Yageo RC0603FR-071ML
39 1 R16A1 10k RES, 0603, 1%, 1/10W A_CR-0603 Yageo RC0603FR-0710KL
40 1 R16A2 1.4K RES, 0603, 1%, 1/10W A_CR-0603 Panasonic ERJ-S03F1401V
41 2 R16A3, R16A4 Open A_CR-0603
42 2 R18A2, R18A5 11.5K RES, 0603, 1%, 1/10W A_CR-0603 Rohm MCR03EZPFX1152
43 2 R18A3, R18A6 9.1K RES, 0603, 1%, 1/10W A_CR-0603 Yageo 9C06031A9101FKHFT
44 1 R18A4 0.887K RES, 0603, 1%, 1/10W A_CR-0603 Rohm MCR03EZPFX8870
45 4
TB1A, TB2A, TB3A,
TB4A T. BLOCK 1 PIN Terminal block TB_1_0 Keystone 8197
46 20
TP37, TP36, TP32,
TP33, TP7, TP11, TP17,
TP35, TP9, TP13, TP21,
TP22, TP15, TP16,
TP28. TP29. TP30,
TP31, TP1, TP2 TP Testpoint V1054_ND Vector K24A/M
47 1 U1A IR3622 MLPQ Controller A_MLPQ32-0P5MM_VIA_A International Rectifier IR3622
48 1 M1A Heat Sink
()
(mm) ThermaFlo 7201598
49 2 TIM1A, TIM2A Thermal Interface Material 7.65 x 20.51 (L x W) (mm) Bergquist BG420754
50 1
SCRW1A
Philips Pan Head Screw Stainless A-2(18-8), 2mm x .4 x 5mm Bolt Depot 6812
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TYPICAL OPERATING WAVEFORMS
Vin=12V, Vo1=2.5V, Vo2=1.8V, Io1=0-20A, Io2=0-20A Fs=350 kHz, Room Temperature, No Air Flow
Fig.13: Start-up sequence into 20A Load.
Ch1: Vin, Ch2: Enable, Ch3: Vss1,Ch
4: Vss2
Fig.14: Start-up sequence into 20A load.
Ch1: Vin, Ch2: Enable, Ch3:V
o1(2V5), Ch4: Vo2(1V8)
Fig.16: Start-up sequence into 20A load.
Ch1: Enable, Ch2:Vss2, Ch3:Vo2(1V8), Ch4:PGood(1V8)
Fig.15: Start-up sequence into 20A load.
Ch1: Enable, Ch2: Vss1, Ch3: Vo1(2V5), Ch4:PGood(2V5)
Fig.17: Inductor points.
Ch1: VL1, Ch2: VL2
Fig.18: Dead-time (rise) at 20A load.
Ch1: VL1
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TYPICAL OPERATING WAVEFORMS
Vin=12V, Vo1=2.5V, Vo2=1.8V, Io1=0-20A, Io2=0-20A Fs=350 kHz, Room Temperature, No Air Flow
Fig.19: Dead-time (fall) at 20A load.
Ch1: VL1
Fig.20: Output voltage ripple at 20A load.
Ch1: Vo1(2V5)
Fig.22: Load transient 0-10A.
Ch1: Vo1(2V5), Ch4: Io1
Fig.21: Output voltage ripple at 20A load.
Ch1: Vo2(1V8), Ch4: Io2
Fig.24: Load Transient 0-10A.
Ch1: Vo1(2V5), Ch4: Io1
Fig.23: Load Transient 10-0A.
Ch1: Vo1(2V5), Ch4: Io1
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TYPICAL OPERATING WAVEFORMS
Vin=12V, Vo1=2.5V, Vo2=1.8V, Io1=0-20A, Io2=0-20A Fs=350 kHz, Room Temperature, No Air Flow
Fig.26: Load Transient 0-10A.
Ch1: Vo2(1V8), Ch4: Io2
Fig.25: Load Transient 0-10A.
Ch1: Vo2(1V8), Ch4: Io2
Fig.28: Hiccup Operation
Ch1: Vo2(1V8), Ch3: VSS2
Fig.27: Hiccup Operation
Ch1: Vo1(2V5), Ch3: VSS1
Fig.29: Inductor Current at 15A load
Ch1: Io1(2V5) Fig. 30: Inductor Current at 15A
Ch1: Io2(1V8)
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TYPICAL OPERATING WAVEFORMS
Vin=12V, Vo1=2.5V, Vo2=1.8V, Io1=0-20A, Io2=0-20A Fs=350 kHz, Room Temperature, No Air Flow
2.4
2.42
2.44
2.46
2.48
2.5
2.52
2.54
2.56
2.58
2.6
0 2 4 6 8 101214161820
Io1 (A)
VO1 (V)
2.5V+3%
2.5V-3%
Fig.31: Vo1 versus its load current.
1.72
1.74
1.76
1.78
1.8
1.82
1.84
1.86
1.88
02468101214161820
Io2(A)
Vo2(V)
1.8V+3%
1.8V-3%
Fig.32: Vo2 versus its load current.
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TYPICAL OPERATING WAVEFORMS
Vin=12V, Vo1=2.5V, Vo2=1.8V, Io1=0-20A, Io2=0-20A Fs=350 kHz, Room Temperature, No Air Flow
Fig .33: Bode Plot of 2.5V loop at 0A shows a bandwidth of 52kHz and phase margin of 48 degree.
Fig. 34: Bode Plot of 2.5V loop at 20 A shows a bandwidth of 61kHz and phase margin of 47 degree.
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TYPICAL OPERATING WAVEFORMS
Vin=12V, Vo1=2.5V, Vo2=1.8V, Io1=0-20A, Io2=0-20A Fs=350 kHz, Room Temperature, No Air Flow
Fig. 35: Bode Plot of 1.8V loop at 0A shows a bandwidth of 39kHz and phase margin of 61 degree.
Fig. 36: Bode Plot of 1.8V loop at 20A shows a bandwidth of 43kHz and phase margin of 58 degree.
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TYPICAL OPERATING WAVEFORMS
Vin=12V, Vo1=2.5V, Vo2=1.8V, Io1=0-20A, Io2=0-20A Fs=350 kHz, Room Temperature, No Air Flow
Fig.37: Thermal Image, Test Points 1, 2, 3, and 4 are Synchronous DirectFET for 2.5V output,
Synchronous DirectFET for 1.8V output, Control DirectFET for 2.5V output, and Control
DirectFET for 1.8V output, respectively.
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Fig. 38: Efficiency of 2.5V channel versus load current with 200LFM air flow and heat sink at
45°C.
TYPICAL OPERATING WAVEFORMS
Vin=12V, Vo1=2.5V, Vo2=1.8V, Io1=0-20A, Io2=0-20A Fs=350 kHz, 45°C, 200LFM Air Flow
Fig.39: Power loss of 2.5V channel versus load current with 200LFM air flow and heat sink at
45°C.
88.0
88.2
88.4
88.6
88.8
89.0
89.2
89.4
89.6
89.8
90.0
90.2
90.4
90.6
90.8
91.0
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Output Current (Amps)
Efficiency %
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Output Current (Amps)
Watts
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TYPICAL OPERATING WAVEFORMS
Vin=12V, Vo1=2.5V, Vo2=1.8V, Io1=0-20A, Io2=0-20A Fs=350 kHz, 45°C, 200LFM Air Flow
Fig.40: Efficiency of 1.8V channel versus load current with heat sink and 200LFM air flow at 45°C.
85.0
85.2
85.4
85.6
85.8
86.0
86.2
86.4
86.6
86.8
87.0
87.2
87.4
87.6
5 6 7 8 9 1011121314151617181920
Output Current (Amps)
Efficiency %
Fig.41: Power loss of 1.8V channel versus load current with heat sink and 200LFM air flow at 45°C.
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
01234567891011121314151617181920
Output Current (Amps)
Watts
22
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FREQUENCY SYNCHRONIZATION
Vin=12V, Vo1=2.5V, Vo2=1.8V, Io1=0-20A, Io2=0-20A, Room Temperature, No Air Flow
The switching frequency of channels can be synchronized by applying a digital input signal to the
Sync pin of the IR3622. This frequency of input is twice as the switching frequency of the
channels.
Fig.42: Frequency Synchronization.
Ch1: VL1(2V5) Ch2: Sync pin Ch3: VL2(1V8)
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OUTPUT VOLTAGE TRACKING AND SEQUENCING
Vin=12V, Vo1=2.5V, Vo2=1.8V, Io1=0-20A, Io2=0-20A, Room Temperature, No Air Flow
In order to run the IR3622 in the ratio-metric mode, the following steps should be taken:
- Remove C29A1, R24A1, R6A1, R16A5 from the board.
-Set the value of R16A3 and R16A4 as R15A (6.49K) and R17A (3.01K), respectively.
-Connect TP33 to the SEQ input signal.
Fig.43: Ratio-metric tracking at the voltage rise to a 20A load.
Ch1: SEQ Ch2: VSS1 Ch3: Vo1(2V5) Ch4:Vo2(1V8)
Fig.44: Ratio-metric tracking at the voltage fall with a 20A load.
Ch1: SEQ Ch2: VSS1 Ch3: Vo1(2V5) Ch4:Vo2(1V8)
24
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OUTPUT VOLTAGE TRACKING AND SEQUENCING
Vin=12V, Vo1=2.5V, Vo2=1.8V, Io1=0-20A, Io2=0-20A, Room Temperature, No Air Flow
In order to run the IR3622 in the simultaneously mode, the following steps should be taken:
- Remove C29A1, R24A1, R6A1, R16A5 from the board.
-Set the value of R16A3 and R16A4 as R18A2 (11.5K) and R18A3 (9.1K), respectively.
-Connect TP33 to the controlling input signal.
Fig.45: Simultaneously Tracking at the voltage rise to a 20A load
Ch1: SEQ Ch2: VSS1 Ch3: Vo1(2V5) Ch4:Vo2(1V8)
Fig.46: Simultaneously Seq. at the voltage fall with a 20A load
Ch1: SEQ Ch2: VSS1 Ch3: Vo1(2V5) Ch4:Vo2(1V8)
25
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TAPE & REEL ORIENTATION
IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105
TAC Fax: (310) 252-7903
This product has been designed and qualified for the Industrial market.
Visit us at www.irf.com for sales contact information
Data and specifications subject to change without notice. 01/23/2007
