TL494: DUTY CYCLE ERROR IN TL494 PWM

BHEEMARAJU G

Part Number: TL494

hello there,

i am using TL494 PWM controller i have a problem with DUTY CYCLE

my minimum duty cycle is 2.24 percent in my sample PCB but in problem PCB it is 3.7 percent

and if i give light load for sample PCB say 40mA current the duty cycle raises to 0.95 percent but in problem PCB it raises to 2.61 percent

can any one suggest what would be the solution or reason in feedback circuit.

THANKS

BHEEM

over 5 years ago

0 Teng Feng over 5 years ago

TI__Genius 13660 points

Hi BHEEN,

The minimal duty cycle at light load depends on the control signal (feedback pin voltage).

May I know what is difference between sample PCB and problem PCB? And also share the schematic.

Regards,

Teng

0 Teng Feng over 5 years ago in reply to Teng Feng

TI__Genius 13660 points

Hi BHEEN, I haven’t heard back from you for quite sometime, I’m assuming you were able to resolve your issue. If not, just post a reply below (or create a new thread if the thread has locked due to time-out) – thanks, Teng.

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TL494: DUTY CYCLE ERROR IN TL494 PWM