lt3825 Linear Technology Corporation, lt3825 Datasheet - Page 9

• Manufacturer Part Number: lt3825
• Description: Isolated No-opto Synchronous Flyback Controller With Wide Input Supply Range
• Manufacturer: Linear Technology Corporation

FLYBACK FEEDBACK AMPLIFIER
TIMING DIAGRAM
R1
R2
8
FB
–
MOSFET DRAIN
PRIMARY SIDE
PG VOLTAGE
SG VOLTAGE
1V
+
VOLTAGE
ENABLE
COLLAPSE
DETECT
LT3825 FEEDBACK AMP
1.25V
V
FB
–
+
R
S
Q
t
ON(MIN)
V
IN
V
FLBK
V
C
ENABLE
DELAY
9
3825 FFA
C
VC
AMPLIFIER
FEEDBACK
MIN ENABLE
ENABLED
V
FLBK
MP
PRIMARY
FLYBACK
V
IN
•
•
T1
•
PG DELAY
SECONDARY
0.8 • V
MS
FLBK
3825 TD
C
OUT
ISOLATED
OUTPUT
LT3825
3825fa
9