ZXSC300
REFERENCE DESIGNS
Two typical LED driving applications are shown.
Firstly a maximum brightness solution and
secondly an optimised battery life solution.
Maximum brightness solution
This circuit provides a constant current output to
the LED by rectifying the switching pulses. This
ensures maximum LED brightness.
L1
D1
VBATT
100µH
ZHCS1000
U1
Vcc
Q1
FMMT617
LED1
Vdrive
Isense
Gnd
ZXSC300
C1
2.2µF
WHITE LED
R1
0.1R
Material List
Ref
U1
Q1
D1
Value
Part Number
ZXSC300E5
FMMT617
ZHCS1000
Generic
Manufacture
Comments
N/A
Zetex Plc
Zetex Plc
Zetex Plc
Various
Various
Coilcraft
Nichia
Single cell converter, SOT23-5
N/A
Low V
NPN, SOT23
CE(sat)
1A
1A Shottky diode, SOT23
0805 Size
R1
100mW
2.2mF
100µH
5600mcd
C1
Generic
Low ESR ceramic capacitor
Surface mount inductor
White LED
L1
DO1608P-104
NSPW500BS
LED1
ISSUE 3 - NOVEMBER 2006
6
ZETEX [ ZETEX SEMICONDUCTORS ]
