ha16178fp Renesas Electronics Corporation., ha16178fp Datasheet - Page 14

• Manufacturer Part Number: ha16178fp
• Description: Power Factor Correction Controller Ic
• Manufacturer: Renesas Electronics Corporation.

HA16178P/FP
2. Operating Frequency
The HA16178 operating frequency fosc is determined by adjusting the timing resistor Rt (the RT pin, pin 9) and the
timing capacitance Ct (the CT pin, pin 10). The operating frequency is approximated by the following expression:
When the IC is operated at high frequencies, the expression becomes less accurate due to IC internal delay time, etc.
Please confirm operation the value with the actually mounted IC. The maximum operating frequency is 400 kHz. As a
reference, the operating frequency data when the timing resistor and the timing capacitance are changed is shown in the
below figure.
REJ03D0903-0100 Rev.1.00 Jun 12, 2007
Page 14 of 24
fosc =
Rt
1000
1.755 × 10
100
(kΩ)
10
1
1
× Ct
(pF)
6
Figure 2 Operating Frequency Characteristics
(kHz)
Timing Resistance (kΩ)
10
100
Timing capacitance
Ct
470 pF
1000 pF
2200 pF
4700 pF