FAN7530 Fairchild Semiconductor, FAN7530 Datasheet - Page 13

• Manufacturer Part Number: FAN7530
• Description: Critical Conduction Mode Pfc Controller
• Manufacturer: Fairchild Semiconductor

FAN7530 Rev. 1.0.2
© 2006 Fairchild Semiconductor Corporation
4. Over-Current Protection Block
The MOSFET current is sensed using an external sens-
ing resistor for the over-current protection. If the CS pin
voltage is higher than 0.8V, the over-current protection
comparator generates a protection signal. An internal RC
filter is included to filter switching noise.
CS
Figure 36. Over-Current Protection Block
4
40k
8pF
0.8V
Over-Current Protection
Comparator
FAN7529 Rev. 00
Signal
OCP
13
5. Switch Drive Block
The FAN7530 contains a single totem-pole output stage
designed for a direct drive of the power MOSFET. The
drive output is capable of up to +500/-800mA peak cur-
rent with a typical rise and fall time of 50ns with 1nF load.
The output voltage is clamped to 13V to protect the
MOSFET gate even if the V
13V.
6. Under-Voltage Lockout Block
If the V
are enabled and start operation. If the V
below 8.5V, most of the internal blocks are disabled to
reduce the operating current. V
higher than 8.5V under normal conditions.
CC
voltage reaches 12V, the IC’s internal blocks
CC
voltage is higher than
CC
voltage should be
CC
voltage drops
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