3-5 Vin 5 Vout 25 mA Out
Reference Design
PRD1146
FEATURES
Extremely low ripple <1 mV
Cost (1k) BOM and Schematic
Simulated to ensure stability
DESCRIPTION
This design is coupled SEPIC converter which converts a 3 -5 V input to a clean 5 V output with very low ripple
noise. The low noise is accomplished with a pi filter on the output. According to a SIMPLIS simulation, Vout
ripple should be 392 uV at Iout equal to 25 mA. The design is specified for 25 mA, but should be able to handle
significantly more output current.
Table 1.
User Target Specs, Vout
Spec
Target
Value
Units
Vout
5V
Volts
Iout
25
mAmps
Tamb
55
degC
Vinmin
3
Volts
Vinmax
5
Volts
Rev. 1
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Reference Design
PRD1146
TABLE OF CONTENTS
Features ......................................................................................................................................................................1 Description .................................................................................................................................................................1 Revision History .........................................................................................................................................................2 Schematic ...................................................................................................................................................................3 Bill of Materials..........................................................................................................................................................3 Graphs ........................................................................................................................................................................5 TABLE OF FIGURES
Figure 1. Schematic ...............................................................................................................................................3 Figure 2. Bode Plot ...............................................................................................................................................5 REVISION HISTORY
9/01/2009—Revision 1: Initial Version
Rev. 1 | Page 2 of 6
Reference Design
PRD1146
SCHEMATIC
Figure 1.
Schematic
BILL OF MATERIALS
Table 2.
Des
Bill of Materials
MFG
Part Number
Component
Specs
Pkg
Qty
Area
(mm^2)
Cost*
U1
ADI
ADP1613ARMZ-R7
Integrated
Switching
Regulator
MSOP-8
1
14.70
$1.200
L1
Coilcraft
LPD3015-3333MLC
33uH, 2.84
Ohms,
0.35Apk
3.3mm x 3.3mm x 1.4mm
1
10.90
$0.600
L2
Coilcraft
1206CS-122
1.2uH, 3.2
Ohms
3.56mm x2.16mm x 1.52mm
1
7.69
$0.300
D1
DiodesInc
B0520LW
0.5A ,20V
SOD123
1
6.63
$0.032
Rev. 1 | Page 3 of 6
Reference Design
Des
MFG
PRD1146
Component
Specs
Part Number
Pkg
Qty
Area
(mm^2)
Cost*
Cin
Taiyo
Yuden
JMK107 BJ105MAT
1uF, 6.3V,
603, X5R
0603
1
1.28
$0.005
Cout1
Taiyo
Yuden
LMK107 BJ105KAT
1uF, 10V, 603,
X5R
0603
1
1.28
$0.005
Cout2
Taiyo
Yuden
LMK107 BJ105KAT
1uF, 10V, 603,
X5R
0603
1
1.28
$0.005
C1
Taiyo
Yuden
LMK107 BJ105KAT
1uF, 10V, 603,
X5R
0603
1
1.28
$0.005
Cv5
Murata
GRM188R61A105K
1uF,10V,X5R
0603
1
1.30
$0.010
Css
Vishay
10% tolerance
10 nF
0402
1
0.70
$0.005
Rc1
Vishay
5% tolerance
10 kohm
0402
1
0.70
$0.005
Cc1
Vishay
10% tolerance
22 nF
0402
1
0.70
$0.005
Cc2
Vishay
10% tolerance
10pF
0402
1
0.70
$0.005
Rf1
Vishay
1% tolerance
102 kohm
0402
1
0.70
$0.005
Rf2
Vishay
1% tolerance
33.2 kohm
0402
1
0.70
$0.005
Rb0
Vishay
5% tolerance
10 Ohm
0402
1
0.70
$0.005
51.24
2.197
Totals
Rev. 1 | Page 4 of 6
16 Reference Design
PRD1146
GRAPHS
Figure 2.
Bode Plot
Rev. 1 | Page 5 of 6
Reference Design
PRD1146
NOTES
©2009 Analog Devices, Inc. All rights reserved.
Trademarks and registered trademarks are the
property of their respective owners. Error! Unknow
Rev. 1 | Page 6 of 6