EV5103 Datasheet, PDF (1/4 Pages) Global Mixed-mode Technology Inc – G5103 White LED Demo Board V1.0

Global Mixed-mode Technology Inc.
EV5103-10
G5103 White LED Demo Board V1.0
Introduction
G5103 is a step-up (boost) DC/DC converter, using constant peak inductor current and minimum OFF
time PFM topology. It could output up to 16V and drive 20mA from a 2.5V ~ 5.5V input power source,
such as a Li-Ion battery. G5103 is suitable for series 2~4 white LED driver application because its
maximum 16V output capability. This solution possess high efficiency about 84% when drive 4 white
LED at 20mA output LED current with a 3.6V Li-Ion battery power input.
This demo board could demonstration:
1. Drive 2 ~ 4 white LED @ 20mA.
2. 200Hz PWM dimming control.
3. Only need 3.0V ~ 5.5V power source. A Li-Ion battery is a good power source.
200Hz PWM Dimming White LED Driver Demo Schematic
JP1
VCC Jumper
VBAT
J1
1
2
3
4
BATT
VCC
VBAT
U2
1
IN
OUT
C3
1uF 2
GND
3
SHDN BYP
G914C
+3VDC
5
C4
1uF
4
C5
0.1uF
+3VDC U3
1
PWM Dim
2
3
4
VDD VSS
GP5 GP0
GP4 GP1
GP3 GP2
8
7
6
5
PIC12C508
SW1
DIM Low
SW2
DIM High
SW3
FREQ
VCC
C1
4.7uF
L1
10uH/0.5A
D1
MBR0530
SW
2 ~ 4 White LED
C2
0.1uF
LED1
LED2
4
SHDN
FB
3
FB
U1
G5103
LED3
LED4
+3VDC
PWM Dim
R3
240K_1%
R4
620K_1%
R2
120K_1%
VISEN
R1
27_1%
18.5mA
PWM Dimming Control Introduction
SW1: Dimming dark ( minimum dimming duty = 0%)
SW2: Dimming light ( maximum dimming duty = 100%)
SW3: Change PWM dimming frequency ( 150Hz 250Hz)
Fig.1
Jan 21, 2003
TEL: [phone]
http://www.gmt.com.tw
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