FA5540 Fuji Electric holdings CO.,Ltd, FA5540 Datasheet - Page 20

• Manufacturer Part Number: FA5540
• Description: Fuji Switching Power Supply Control Ic
• Manufacturer: Fuji Electric holdings CO.,Ltd

9. Description of the function
Rev.0 July-2007
(1) Steady- state operation
At each switching cycle, TURN ON is carried out at the first Valley signal that exceeds the time corresponding to the
maximum frequency limit of 60kHz(FA5540)/120kHz(FA5541/42), counting from the previous TURN ON.
Max. fsw
最大
Valley
signal
pulse
Val
信号
OUT
パル
Out
Vds
ley
fsw
ス
120kHz(FA5541/42)
60kHz(FA5540)
Fig.3 Steady-state operation timing chart
Heavy load
120kHz(FA5541/42)
FA5540/5541/5542
60kHz(FA5540)
middle load
20
120kHz(FA5541/42)
60kHz(FA5540)
light load (stand-by)
Fuji Electric Device Technology