IRDC38060-P1V2
SupIRBuck
DESCRIPTION
TM
USER GUIDE FOR IR38060 EVALUATION BOARD
The IR38060 is a synchronous buck
converter with a PMBus interface, providing
a compact, high performance and flexible
solution in a small 5mmx6mm PQFN
package.
Key features offered by the IR38060 include
I2C/PMBus configurability of output voltage,
soft-start, input UVLO, input overvoltage
protection, output overvoltage protection,
output overcurrent protection, Power Good,
thermal protection and switching frequency.
Additionally, the IR38060 also features
enhanced line/ load regulation with feed
forward, external frequency synchronization
with smooth clocking, internal LDO, true
differential remote sensing
and pre-bias
start-up.
A temperature and bias compensated output
over-current protection function is implemented
by sensing the voltage developed across the
on-resistance of the synchronous rectifier
MOSFET for optimum cost and performance.
This user guide contains the schematic and bill
of materials for the IR38060 evaluation board.
The guide describes operation and use of the
evaluation board itself. Detailed application
information for IR38060 is available in the
IR38060 data sheet.
BOARD FEATURES
•
PVin = +12V (+ 13.2V Max),
No Vcc required.
• V
out
= +1.2V @ 0-6A
•
F
s
= 600kHz
•
L= 0.82uH
•C
in
= 3x22uF (ceramic 1206) + 1x330uF (electrolytic, optional)
•
C
out
=7x22uF (ceramic 0805)
10/20/2015
1
IRDC38060-P1V2
CONNECTIONS and OPERATING INSTRUCTIONS
A well regulated +12V input supply should be connected to PVin+ and PVin-. A maximum of 6A load should
be connected to VOUT+ and VOUT-. The inputs and output connections of the board are listed in Table I.
IR38060 needs only one input supply and internal LDO generates Vcc from PVin. Another internal LDO
generates the 1.8V needed by the internal digital circuits. If operation with external Vcc is required, then R25
should be removed and external Vcc can be applied between Vcc+ and Vcc- pins. Vin pin and Vcc pins
should be shorted together for external Vcc operation by installing R24.
The board is configured for remote sensing. If local sense is desired, R8 should be uninstalled and R16
should be installed instead.
I2C/PMBus communication is established through the 4 pin header which allows connection to the
SCL/SDA/SALERT and GND lines from the host/dongle. For proper operation in digital communications
mode, R35 must always be populated.
External Enable signal can be applied to the board via exposed Enable pad and
R18 should be removed for
Table I. Connections
this purpose.
Connection
PVin+
PVin-
Vout+
Vout-
Signal Name
PVin (+12V)
Ground of PVin
Vout(+1.2V)
Ground for Vout
Vcc+
Vcc-
Enable
PGood
Vcc Pin
Ground for Vcc input
Enable
Power Good Signal
LAYOUT
The PCB is a 4-layer board. All of layers are 2 Oz. copper. The IR38060 and most of the passive
components are mounted on the top side of the board.
Power supply decoupling capacitors and feedback components are located close to IR38060. The
feedback resistors are connected to the output of the remote sense amplifier of the IR38060 and are
located close to the IR38060. To improve efficiency, the circuit board is designed to minimize the length
of the on-board power ground current path. Separate power ground and analog ground are used and
may be connected together using a 0 ohm resistor.
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2
IRDC38060-P1V2
CONNECTION DIAGRAM
PVin
Vout
PGood
Top View
Enable
I2C / PMBus
Communication
Bottom View
10/20/2015
3
1
1
1
N/S
R21
1
1
1
1
C27
R19
ADDR
VIN
Vsns
R22
R25 0
0 ohm
PVin+
6
5
4
3
2
1
1
1
VCC
C80
C28
49.9k
VCC
N/S
7.5k
1
1
4
15
11
22
Vp
PGood
8
RSo
PVin
C35
1uF
+
Vcc
En/FCCM
1
1
1
19
SCL/OC
Vcc
R29 N/S
18
SDA/IMON
Vsns
2
Vsns
R14
7X22uF/805/6.3V
SCL/OCSet
SPM6550T-R82M, 0.82uH
5
BODE2
1
R10
0
R32
N/S
R11
Vo_R_N
0
LGnd
1
+
+
SW
C42 C43
C44
C45
C46
C47
C48
C49
C50
22uF 22uF 22uF N/S
C51
N/S
C52
N/S
C53
0.1uF
6
5
4
3
2
1
1
Rt/Sync
ADDR
LGnd
RS-
14
16
13
9
R9
R35
0
2200pF
C8
BODE1
2
R6
20
C67
N/S
1
R16
N/S
R4
130
Fb
R3
R38
Sy nc
N/S
N/S
1
66.5k
J1
SCL
SDA
R2
4.02k
CLK
DATA
GND
0
R37
ALERT#
R40 R36
0
0
Sy nc
SDA/IMON
TMON
N/S
R33
N/S
Rt/Sy nc
1
SCL/OC
IMON
1
N/S
SAlert/TMON
R34
R59
R39
0
Vsns
IRDC38060-P1V2
Fig. 1: Schematic of the IR38060 evaluation board
1
10/20/2015
VDDQ
R20
VDDQ
PGND
VIN
Vsense
VCC-
VCC+
ADDR
En/FCCM
R18
Vp
N/S
N/S
R23 4.99k
21
VIN
1
PVin
C1
330uF
0 ohm
PVin-
6
5
4
3
2
1
Vo_R_P
R41
0
SWs
L1
C10
SW
0.1uF
24
0
KC3
Vout_+
Vout+
6
5
4
3
2
1
Vout-
R26
R24 N/S
VCC
10uF
PGood
R8
0
Vin
6
FB
Comp
U1
Track_En
P1V8
IR38060
Boot
2
PGnd
PGnd12
PGnd25
7
Track_Enb
R58
N/S
R28 N/S
N/S
20
1.8V
3
R27
23
12
25
C29
22uF
C30
22uF
C32
N/S
C36
0.1uF
C31
22uF
C33
N/S
R30 N/S
R15
N/S
Vo_R_P
0
R31 4.99k
RS+
C54
N/S
10
C41
2.2uF
SDA/IMON
17
SAlert/TMON
SAlert/TMON
22uF 22uF 22uF 22uF
0.1uF
Vo_R_N
0
C65
N/S
C66
N/S
KC4
Vout_-
Rt/Sy nc
ADDR
C11
270pF
R1
2k
C26
10nF
4
IRDC38060-P1V2
Bill of Materials
Item Quant
Number ity
Part Reference
1
2
3
4
5
6
7
8
Value
Description
SMD Electrolytic, F size, 25V,
20%
2200pF, 0603, 50V, NPO
50V, 0603, NP0, 5%
0603, 50V, X7R, 10%
22uF, 1206, 25V, X5R, 20%
0603, 50V, X7R, 10%
0603, X5R, 25V, 20%
0805, 6.3V, X5R, 20%
Manufacturer
Panasonic
TDK
Murata
Murata
TDK
Panasonic
TDK
Murata
Part Number
EEE-FK1E331P
C1608C0G1H222J
GRM1885C1H271JA01D
GRM188R71H103KA01D
C3216X5R1E226M160AB
ECJ-1VB1H104K
C1608X5R1E105M
GRM21BR60J226ME39
9
10
11
12
13
14
15
16
17
18
1 C1
330uF
1 C8
2200pF
1 C11
270pF
1 C26
10nF
3 C29 C30 C31
22uF
4 C10 C36 C42 C53 0.1uF
1 C35
1uF
C43 C44 C45 C46
7 C47 C48 C49
22uF
LGND 1.8V ADDR
EN/FCCM IMON
PGND PGOOD SW
SYNC TMON
VCC+ VCC- VDDQ
VIN VIN_+
0.075"
VOUT_+ VOUT_- SQ_SMT_
19 VP VSENSE
TestPoint
1 J1
1 C41
1 R19
1 L1
1 R1
1 R2
1 R9
1 R4
1 R6
R8 R10 R11 R14
R25 R35 R36 R37
11 R39 R40 R41
1 R18
2 R22 R26
2 R23 R31
1 C80
1 U1
TP-200-125
Header-4P
2.2uF
0603, 10V, X5R, 20%
7.5k
0603,1/10W,1%
0.82uH
0.82uH, DCR=4.3mohm
2k
0603, 1/10W, 1%
4.02k
0603, 1/10W, 1%
66.5k
0603, 1/10W, 1%
130
0603, 1/10W, 1%
20
0603, 1/10W, 1%
TDK
Rohm
TDK
Rohm
Rohm
Rohm
Rohm
Rohm
C1608X5R1A225M080AC
MCR03EZPFX7501
SPM6550T-R82M
MCR03EZPFX2001
MCR03EZPFX4021
MCR03EZPFX6652
MCR03EZPFX1300
CRCW060320R0FKEA
19
20
21
22
23
24
0 ohm
49.9k
0 ohm
4.99k
10uF
IR38060
0603, 1/10W
0603, 1/10W, 1%
1206, 1/4 W
0603, 1/10W, 1%
0603, 10V, X5R, 20%
IR38060 5mm X 6mm
Rohm
Rohm
Panasonic
Rohm
Murata
International
Rectifier
CRCW06030000Z0EA
MCR03EZPFX4992
ERJ-8GEY0R00V
MCR03EZPFX4991
GRM188R61A106ME69D
IR38060
•The electrolytic input capacitor used on this demo board is to eliminate the impact of the parasitic inductance of a long input power cable. It
may not be necessarily needed in real applications.
5
06-18-2013