REFERENCE DESIGN
International Rectifier
IRDCiP1001-A
• 233 Kansas Street, El Segundo, CA 90245 USA
IRDCiP1001-A, 200kHz, 20A, 3.3VIN to 4.5VIN Single Phase
Synchronous Buck Converter using iP1001
Overview
In this document, Table 1 and Figure 1 are provided to enable engineers to
easily evaluate the iP1001 in a single phase configuration that is capable of
providing up to 20A in a lab environment without airflow. Figures 3, 4, 5 and
6 and the complete bill of materials in Table 2 are provided as a reference
design to enable engineers to very quickly and easily design a single phase
converter. In order to optimize this design to your specific requirements,
refer to the iP1001 data sheet for guidelines on external component selection
and user adjustable limits and specifications. Custom designs may require
layout modifications.
Demoboard Quick Start Guide
Initial Settings:
IRDCiP1001-A Demoboard
Operatng Conditions
Min
Max
VIN
3.3V
4.5V
VOUT
0.925V
2.5V
IOUT
See Fig.1
z The output is set to 2V, but can be adjusted from 0.925V to 2.0V by
setting SW1 according to the VID codes provided in Table 1. The output voltage can also be adjusted to allow up to
2.5VOUT for 3.3VIN, by adding R3 & R4 with the DAC set to 2VOUT. Refer to equation 1 for R3 & R4 values. R4 should
be removed for output voltages below 2V, and R3 should be set to zero ohms (see Table 2).
z The switching frequency is centered around 200kHz for <5VIN applications with the FREQ pin connected to VDD.
z The input voltage range can be increased to allow operation between 5VIN and 12VIN. Refer to IRDCiP1001-B reference
design documentation for direction on changing the configuration of the demo board.
Procedure for Connecting and Powering Up Demoboard:
1. Apply input voltage (3.3V-4.5V) across VIN and PGND. Note that this demo board has a mini-boost circuit
provided in order to provide the 5VDD internal logic for the iP1001. This boost circuit can be used to provide power for
up to 5 x iP1001 devices simultaneously.
2. Apply load across VOUT pad and PGND pad.
3. Make sure Jumpers JP2 and JP3 are connected.
4. Remove jumper JP1 to turn on the boost circuit and pull iP1001 ENABLE pin high. The ENABLE pin is controlled via switch
8 on SW1. This pin is supplied in low state, once pulled high the output is enabled.
5. Adjust load accordingly.
IRDCiP1001-A Recommended Operating Conditions
(refer to the iP1001 datasheet for maximum operating conditions)
Input voltage:
3.3 - 4.5V (VDD provided by mini boost circuit)
Output voltage:
DAC selectable between 0.925V - 2.0V (with extended operating range to 3.3V with R3 & R4)
Output current:
Up to 20A depending on duty factor (refer to recommended operating area Fig.1).
Switching Freq:
200kHz or 300kHz selectable.
09/11/02
IRDCiP1001-A
25
Load Current (A)
20
VIN = 5V to 12V
200kHz/300kHz
15
VIN = 3.3V,
200kHz
10
5
0
0.9
1.2
1.5
1.8
2.1
2.4
2.7
3.0
3.3
Output Voltage (V)
Fig. 1 - Recommended Operating Area
D4
D3
D2
D1
D0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
Output
Voltage
(V)
2.00
1.95
1.90
1.85
1.80
1.75
1.70
1.65
1.60
1.55
1.50
1.45
1.40
1.35
1.30
Shutdown*
D4
D3
D2
D1
D0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
Output
Voltage
(V)
1.275
1.250
1.225
1.200
1.175
1.150
1.125
1.100
1.075
1.050
1.025
1.000
0.975
0.950
0.925
Shutdown*
* Shutdown : Upon receipt of the shutdown code (per VID code table above), both FETs are turned OFF and the output
is discharged as it enters UVP fault mode.
Table 1 - iP1001 VID Code
For output voltages above the DAC maximum setting of 2V, refer to Equation 1 below to calculate the
required resistor values for R3 & R4 (needed in order to achieve the extended output voltage range).
Equation 1 : Vout = VF . {1 + R3/R4}
where VF is equal to the DAC setting
and R4 is recommended to be ~1kΩ
2
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IRDCiP1001-A
98%
Efficiency
96%
TA = 25°C
94%
92%
90%
3.3Vin, 2.5Vout, 200KHz
3.3Vin,1.8Vout, 200KHz
88%
86%
0
5
10
15
20
Output Current (A)
Fig. 2 - Typical Efficiency vs. Current
Refer to the following application notes for detailed guidelines and suggestions when
implementing iP0WIR Technology products:
AN-1028: Recommended Design, Integration and Rework Guidelines for International Rectifier’s
iPOWIR Technology BGA Packages
This paper discusses the assembly considerations that need to be taken when mounting iPOWIR BGA’s
on printed circuit boards. This includes soldering, pick and place, reflow, inspection, cleaning and
reworking recommendations.
AN-1029: Optimizing a PCB Layout for an iPOWIR Technology Design
This paper describes how to optimize the PCB layout design for both thermal and electrical performance.
This includes placement, routing, and via interconnect suggestions.
AN-1030: Applying iPOWIR Products in Your Thermal Environment
This paper explains how to use the Power Loss and SOA curves in the data sheet to validate if the
operating conditions and thermal environment are within the Safe Operating Area of the iPOWIR product.
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3
IRDCiP1001-A
LBI
3
C19
0.1µF
LX
LBO
GND
REF
SHDN
7
L2
6
22µH
MAX1675
R8
100K
2
C17
10µF
C20
1µF
5
JP1
1
C18
10µF
JP2
VIN
2
1
4
8
OUT
1
FB
2
JP3
Optional
U2
1
3.3-4.5V
2
C1
C2
C3
100uF 100uF 100uF
6.3V 6.3V 6.3V
+5V
TP1
VDD
VIN
U1
L1
1.06uH
VSW
VO
TP4
VOS
R1
VOUT
0
TP3
+5V
1
2
3
4
5
6
7
8
SW1
16
15
14
13
12
11
10
9
C11
C12
C13
C14
470uF 470uF 470uF 470uF
6.3V 6.3V 6.3V 6.3V
PGOOD
C16
0.1µF
D1
10MQ040N
PGND
D4
D3
D2
D1
D0
FREQ
iP1001
iP1001
ENABLE
R9
91K
R3
C21
47pF
R4
PGND
TP5
R5
ILIM
R7
340K, 1%
VF
R2
PGND
SGND
VFS
R6
0
GND
TP2
Fig. 3 - Reference Design Schematic
4
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IRDCiP1001-A
Fig. 4 - Component Placement (Top View)
Fig. 5 - Component Placement (Bottom View)
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5
IRDCiP1001-A
IRDCiP1001-A (For operation <4.5VIN)
Designator
Value
C1, C3, C5
100uF
C2, C4, C6, C7, C8, C9, C10, C15
C11, C12, C13, C14
470uF
C16, C19
0.100uF
C17, C18
10.0uF
C20
1.00uF
C21
47.0pF
D1
40V
JP1, JP2, JP3
JP1-1, JP2-1, JP3-1
L1
1.06uH
L2
22uH
R1
0:
R2
-
R3
-
Part Type
Capacitor, 6.3V, 20%, X5R
Not Installed
Capacitor, 6.3V, 20%, Tantalum
Capacitor, 50V, 10%, X7R
Capacitor, 16V, 10%, X5R
Capacitor, 10V, 10%, X7R
Capacitor, 50V, 5%, C0G
Schottky Diode, 40V, 2.1A
Test Point
Shunt
Inductor, 16A, 20%, Ferrite
Inductor, 0.68A, 20%, Ferrite
Resistor, 0: Jumper
For <2Vout, Not installed
For >2Vout, Resistor, 0: Jumper
For <2Vout, Resistor, 0: Jumper
For >2Vout see formula for value
For <2Vout, Not installed
For >2Vout recommend 1k:
see formula for detail
For <2Vout, Resistor, 0: Jumper
For >2Vout, Not installed
Resistor, 0: Jumper
Resistor, 340k:, 1%
340k: sets for 20A limit.
See ILIM formula for other values
Resistor, 100k:, 5%
Resistor, 91k:, 5%
8-position DIP switch
Not Installed
Test Point
R4
R5
-
R6
0:
R7
340k:
R8
R9
SW1
TP1, TP3
TP2, TP4, TP5
100k:
91k:
-
U1
-
Power Block
U2
-
IC, Step-Up DC-DC Converter, 0.5A
Footprint
1812
7343
1206
1210
0805
1206
D-64
SMT
SMT
2716
Mfr.
Mfr. P/N
TDK
C4532X5R0J107MT
Sanyo
6TPB470M
Novacap
1206B104K500N
TDK
C3225X5R1C106KT
MuRata
GRM40X7R105K010
MuRata
GRM42-6C0G470J050A
International Rectifier
10MQ040N
Samtec
TSW-102-07-LS
Samtec
SNT-100-BKT
Panasonic
ETQP6F1R1BFA
Sumida
CR43-220
Isotek Corp
SMT-R000
SMT
-
-
SMT
-
-
SMT
-
-
1206
Panasonic
ERJ-8GEY0R00
1206
-
-
1206
ROHM
MCR18EZHF3403
1206
ROHM
1206
ROHM
SMT
C&K Components
Keystone
SSBGA
International Rectifier
14mmx14mm
8uMAX
Maxim
MCR18EZHJ104
MCR18EZHJ913
SD08H0SK
1502-2
iP1001
MAX1675EUA
Table 2 - Reference Design Bill of Materials
Current Limit Resistor Rlim in kOhms
Adjusting the Current Limit
900
800
700
600
500
400
300
200
100
0
6
11
16
21
26
31
36
Typical Current Limit Setting in Amps
Fig. 6 Current Limit Adjustment using RLIM
Use of this design for any application should be fully verified by the customer.
International Rectifier cannot guarantee suitability for your applications, and is not liable
for any result of usage for such applications including, without limitation, personal or
property damage or violation of third party intellectual property rights.
IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, USA Tel: ++ 1 310 252 7105
Technical Assistance Center (TAC) Fax : ++ 1 310 252 7903
6
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