The circuit shown here will achieve a constant

volt-second product clamp over varying input

are chosen so that the ramp at Pin 9 crosses the 1V

threshold at the same time the desired maximum

volt-second product is reached. The delay through the

inverter must be such that the ramp capacitor can be

completely discharged during the minimum deadtime.

UC1823

UC2823

UC3823

OUTPUT SECTION

FEED FORWARD TECHNIQUE FOR OFF-LINE VOLTAGE MODE APPLICATION

UNITRODE CORPORATION

7 CONTINENTAL BLVD.

• MERRIMACK, NH 03054

TEL. (603) 424-2410

• FAX (603) 424-3460

CONSTANT VOLT-SECOND CLAMP CIRCUIT

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