ld7522 Leadtrend Technology, ld7522 Datasheet - Page 3

• Manufacturer Part Number: ld7522
• Description: Smart Green-mode Pwm Controller With Multiple Protections
• Manufacturer: Leadtrend Technology

Block Diagram
Leadtrend Technology Corporation
LD7522-DS-03 January 2008
(-) LATCH
COMP
BNO
OVP
CS
Vbias
5V
5V
Vbias
1.25V
/1.10V
100uA
3.5V/
2.5V
2.5V
5.0V
8V
Blanking
Leading
Green-Mode
Edge
www.leadtrend.com.tw
= 0.04
Control
Gain
65KHz
OSC
PDR
Comparator
Latch Protection
Comparator
Brownout
Comparator
OVP
Comparator
OLP
Comparator
2R
Line
Compensation
R
0.85V
30mS
Delay
1 =OVP
∑
∑
PG
+
+
16V/10V
+
+
Slope
Compensation
32V
Line
Compensation
3
VCC
PG
GND
OCP
Comparator
Auto-Recoverable Protections
PWM
Comparator
1 =Power Down Reset
1 = ACUV
1 =OLP
UVLO
Comparator
0 =Enable
1 =Disable
Latched Protections
PG
internal bias
& Vref
S
R
S
R
S
R
Driver
Stage
VCC OK
Q
Q
Q
Vref OK
LD7522
PG
OUT