HA16158P Datasheet, PDF (14/23 Pages) Renesas Technology Corp – PFC & PWM Control IC

HA16158P/FP
4. PFC On/Off Function
On/off control of the PFC function can be performed using the PFC-ON pin.
If an AC voltage that has undergone primary rectification and has been divided by an external resistance is
input, it is possible to halt PFC operation in the event of a low input voltage. On/off control is also possible
by using a logic signal.
This IC also incorporates a function that automatically detects a 100 V system or 200 V system AC voltage
at the PFC-ON pin, and switches multiplier gain and the PFC-CS comparison voltage.
These functions simplify the design of a power supply compatible with worldwide input.
Rec+
Em
R1
720kΩ
PFC-ON
5
PFC-ON(dc)
C1
R2
2.2µF 12kΩ
1.5V
1.2V
PFC-ON/OFF control
Multiplier gain switching
3.8V
PFC-CS compare
3.4V
voltage switching
PFC-ON(dc) = 2 ∗ Em / π ∗ R2 / (R1 + R2)
= 2 ∗ √2 ∗ Vac / π ∗ R2 / (R1 + R2)
AC Voltage
Vac
0Vac
62Vac
PFC-ON
1.5V
0V
ON
PFC status
(internal signal)
OFF
0.25
Multiplier gain
(internal signal)
0.05
PFC-SS ^–0.25
compare
voltage
(internal signal) –0.50
156Vac
3.8V
140Vac
3.4V
49Vac
1.2V
PFC ON period
Figure 4
Rev.0, Aug. 2002, page 14 of 23