ame5142 AME, Inc., ame5142 Datasheet - Page 10

• Manufacturer Part Number: ame5142
• Description: White Led Boost Converter In Tiny Package
• Manufacturer: AME, Inc.

n Application Hints
10
AME5142
pin.
higher than the maximum enable voltage of EN pin, in order to let the dimming control perform correctly.
Dimming Control
A. Using a PWM Signal to EN Pin
For controlling the LED brightness, the AME5142 can perform the dimming control by applying a PWM signal to EN
The average LED current is proportional to the PWM signal duty cycle. The magnitude of the PWM signal should be
150
125
100
75
50
25
0
0.2
AME, Inc.
V
FB
0.4
VS Duty Cycle
Duty Cycle
4.7 F
C
IN
Dimming
150KHz
Control
V
Figure 5. PWM Dimming Control Using the EN Pin
0.6
IN
3.3V
IN
EN
GND
0.8
AME5142
22 H
L1
OVP
SW
FB
20
18
16
14
12
10
8
6
4
2
0
0.2
White LED Boost Converter
I
OUT
7.5
0.4
R1
VS Duty Cycle
Duty Cycle
V
OUT
2.2 F
C
In Tiny Package
OUT
0.6
0.8
Rev. A.04