ha16158 Renesas Electronics Corporation., ha16158 Datasheet - Page 18

• Manufacturer Part Number: ha16158
• Description: Pfc & Pwm Control Ic
• Manufacturer: Renesas Electronics Corporation.

HA16158P/FP
7. Operating Frequency
The operating frequency is adjusted by timing resinstance RT.
Adjustment examples are shown in the graph below. The operating frequency fpwm in the PWM section is determined
by the RT. The operating frequency fpfc in the PFC section is half the value of fpwm.
The operating frequency in the PWM section can be estimated using the approximate equation shown below.
RT = 200 kΩ:
This is only an approximate equation, and the higher the frequency, the greater will be the degree of error of the
approximate equation due to the effects of the delay time in the internal circuit, etc.
When the operating frequency is adjusted, it is essential to confirm operation using the actual system.
Rev.2.00 Jan 30, 2007 page 18 of 23
fpwm ≈
fpfc =
1000
100
fpwm
10
2.60 × 10
2
10
RT
= 65 [kHz]
10
= 130 [kHz]
Figure 8
RT (kΩ)
100
fpwm
fpfc
1000