ZXSC300
Maximum battery life solution
To ensure optimum efficiency, and therefore
maximum battery life, the LED is supplied with a
pulsed current. Maximum efficiency is ensured with
the removal of rectifier losses experienced in the
maximum brightness solution.
100
95
Single LED Load
L1
VBATT
100µH
U1
Q1
FMMT617
Vcc
LED1
V
drive
WHITE LED
Isense
Gnd
90
ZXSC300
R1
0.33R
85
1.0
1.5
2.0
2.5
3.0
3.5
Input Voltage (V)
Input Voltage v Efficiency
Materials list
Ref
U1
Value
N/A
Part Number
ZXSC300E5
FMMT617
Manufacture
Zetex Plc
Zetex Plc
Various
Comments
Single cell converter, SOT23-5
Q1
N/A
Low V
NPN, SOT23
CE(SAT)
R1
330mW
100mH
5600mcd
Generic
0805 Size
L1
DO1608P-104
NSPW500BS
Coilcraft
Nichia
Surface mount inductor
White LED
LED1
ISSUE 3 - NOVEMBER 2006
7
ZETEX [ ZETEX SEMICONDUCTORS ]
