FAN6300DY Fairchild Semiconductor, FAN6300DY Datasheet - Page 3

• Manufacturer Part Number: FAN6300DY
• Description: Fan6300 - Highly Integrated Quasi-resonant Current Mode Pwm Controller
• Manufacturer: Fairchild Semiconductor

© 2008 Fairchild Semiconductor Corporation
FAN6300 • Rev. 1.0.3
Marking Information
Pin Configuration
Pin Definitions
Pin #
1
2
Name
DET
FB
- Generates a ZCD signal once the secondary-side switching current falls to zero.
- Produces an offset voltage to compensate the threshold voltage of the peak current limit to
- Detects the valley voltage of the switching waveform to achieve the valley voltage switching
Description
This pin is connected to an auxiliary winding of the transformer via resistors of the divider for
the following purposes:
A voltage comparator and a 2.5V reference voltage develop an output OVP protection. The
ratio of the divider decides what output voltage to stop gate, as an optical coupler and
secondary shunt regulator are used.
The Feedback pin is supposed to be connected to the output of the error amplifier for achieving
the voltage control loop. The FB should be connected to the output of the optical coupler if the
error-amplifier is equipped at the secondary-side of the power converter.
For the primary-side control application, this pin is applied to connect a RC network to the
ground for feedback-loop compensation.
The input impedance of this pin is a 5kΩ equivalent resistance. A 1/3 attenuator connected
between the FB and the PWM circuit is used for the loop gain attenuation.
FAN6300 performs an open-loop protection once the FB voltage is higher than a threshold
voltage (around 4.2V) more than 55ms.
provide a constant power limit. The offset is generated in accordance with the input voltage
when PWM signal is enabled.
and minimize the switching losses.
Figure 4. Pin Configuration
Figure 3. Marking Diagram
Z:
X:
Y:
TT:
T: Package type (D =DIP, S = SOP)
P:
M: Manufacturing flow code
: Fairchild logo
Plant Code
Year Code
Week Code
Y = Green Package
Die Run Code
3
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