Diodes AP1681 - Manual (Page 3)

Preliminary Datasheet
Off-line Primary Side Regulation Controller for Dimmable LED Driver AP1681
Jul. 2011 Rev. 1. 2 BCD Semiconductor Manufacturing Limited
3
Functional Block Diagram
Regulator
&
Bias
Protection
& Latch
Tonsec
Detector
0.1V
4V
CC_CTRL
Tons
COMP
COMP
UVLO
pro
pfm
Driver
FB
CS
DIM
VCC
OUT
GND
RI RD
R
Q
S
pro
Demag
CV_CTRL
COMP
FB_ACC
1.75V
VCC_OVP
4V
COMP
PEAK_CTRL
0.5V
COMP
SHORT_OCP
SHORT_OCP
VCC_OVP
FB_OVP
OTP
Constant
Current
Control
CC_CTRL
CC_ON
CC_ON
Reference
COMP
FB_OVP 8V
Dimming Control
S Q
R
CC_CTRL
1
2 3
4
5
6
7
8
Figure 3. Functional Block Diagram of AP1681