ha16174p Renesas Electronics Corporation., ha16174p Datasheet - Page 19

• Manufacturer Part Number: ha16174p
• Description: Power Factor Correction Controller Ic
• Manufacturer: Renesas Electronics Corporation.

HA16174P/FP
4-2. Operation on a Momentary Outage
(1) When the Momentary Outage is Short
Rev.1.00 Jan 06, 2006 page 19 of 36
Full-wave rectified AC
During a momentary outage, the voltage on the PFC-ON pin is discharged. When it reaches 1.6 V, charging of the
capacitor on the DELAY pin starts. The voltage on the PFC-ON pin continues to fall and, when it reaches 1.4 V,
source current begins to flow through the pin. The lower the PFC-ON voltage, the greater the amount of current, so
the PFC-ON pin voltage does not fall below the level determined by the external resistor and the source current.
AC-voltage input is resumed, if the DELAY pin voltage doesn’t reach 1.25 V before the PFC-On pin voltage rises
above 1.75 V, the PFC output voltage resumes quickly. In this case, the soft-start function does not operate.
The hold time for PFC operation is adjusted by the value of the capacitance on the DELAY pin. Note, however, that
if VCC voltage of IC is not normally supplied during a momentary outage, the PFC-ON hold function does not
operate.
PF output voltage
(PFC operation hold on momentary outage: PFC hold function)
PFC-ON
DELAY
Ipfc-on
OUT
Figure 6 PFC Hold Function Operation Waveform 1
1.6 V
1.75 V
1.25 V