M51995AFP#CF0J Renesas Electronics America, M51995AFP#CF0J Datasheet - Page 36

• Manufacturer Part Number: M51995AFP#CF0J
• Description: IC SWIT PWM SMPS OVP UVLO 20SOIC
• Manufacturer: Renesas Electronics America

Specifications of M51995AFP#CF0J

• Output Isolation: Isolated
• Frequency Range: 170 ~ 207kHz
• Voltage - Input: 9.9 ~ 36 V
• Power (watts): 1.5W
• Operating Temperature: -30°C ~ 85°C
• Package / Case: 20-SOIC (0.200", 5.30mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

M51995AP/AFP
REJ03D0835-0300 Rev.3.00 Jun 06, 2008
Page 34 of 40
(2) In case of fly back system
Figure 34 shows how to control the knee point where the frequency becomes decrease,
The DC output voltage of SMPS depends on the V
winding is negative and the system is fly back. So the operation of type M51995A will stop when the V
becomes lower than “Operation-stop voltage” of M51995A when the DC output voltage of SMPS decreases
under specified value at over load condition.
From
V
OUT
Figure 33 Feed Back Loop through Low Pass Filter from V
Figure 36 Circuit Diagram to make Knee Point Low on Fly Back System
Figure 35 Over Current Limiting Curve on Fly Back System
To VF
Figure 34 How to Control the Knee Point
DC Output Current
M51995A
V
From
V
CC
OUT
To make the knee
point high
R
C
VFFB
Collector
VFFB
CC
VF
Voltage of type M51995A when the polarity of the third
Point that V
or third winding
voltage decreases
under "Operation-Stop Voltage"
V
VF
OUT
M51995A
R1
R2
To VF
C
+
CC
VCC
voltage
From
V
OUT
OUT
To make the knee
point low
to V
F
Terminal
To VF
CC