SP7648
Evaluation Board Manual
Easy Evaluation for the
SP7648 Single or Dual Cell
Alkaline to 2V to 5V Output
Provides 700mA output at
3.6V output for Li-Ion Input
High Efficiency: 94%
碌SOIC
Package & SMT
components for small, low
profile Power Supply
DESCRIPTION
The
SP7648 Evaluation Board
is designed to help the user evaluate the performance of the
SP7648 for use as a single/dual cell Alkaline or single cell Li-Ion to drive 1W LED. The output of
the SP7648 is preset to +5V or can be adjusted from +2V to +5V by manipulating two external
resistors. The evaluation board is a completely assembled and tested surface mount board
which provides easy probe access points to all SP7648 Inputs and Outputs so that the user can
quickly connect and measure electrical characteristics and waveforms.
SP7648 EVALUATION BOARD SCHEMATIC
Vin 3.0-4.2V
C1
10uF
0805
RLIM1
OPEN
SW1
1
2
D1
Shorted
1
WURTH(744042004)
L1 4.7uH
SP7648
VBATT
FLASH
NC
RLIM
SHDN
VOUT
LX
PGND
GND
FB
10
9
8
7
6
Important:
0.1uF Ceramic Cap at Vout Pin
needed for stable regulation
C4
0.1uF
Rc
0.33 Ohm
C2
10uF
0805
Vout
D2
1W LED
Mode Out (TP)
2
3
4
5
C3
470pF
R6 1K
ON / OFF
R5
1M
RLIM
1K
Vref
Flash: Iout = 0.3V/((R2//R4+Q1 RDSon)//R1)
Torch: Iout = 0.8V/R1
Flas h: FLASH = H
Torch: FLASH = L
J3 FLASH
1
2
3
R2
0.33 Ohm
0603
R4
open
R1
4.02 Ohm
0603
R3
open
Q1
MOSFET N
Si1400DL
SC-70
Rev 5/17/05
SP7648 Evaluation Board Manual
Copyright 2005 Sipex Corporation
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