Integrated self-driven active clamp
AssigneeSilanna Asia Pte Ltd
InventorAleksandar Radic
Life of this patent
Estimating the term…
Abstract
An active clamp circuit includes an active clamp capacitor coupled in series with an active clamp switch and an active clamp controller circuit to receive an active clamp switch current that passes through the active clamp switch and to control the active clamp switch based on the received active clamp switch current. The active clamp controller circuit is configured to enable the active clamp switch based on a first amplitude comparison, the first amplitude comparison being based on the active clamp switch current. The active clamp controller circuit is configured to disable the active clamp switch based on a second amplitude comparison and a third amplitude comparison, the second amplitude comparison and the third amplitude comparison being based on the active clamp switch current.
Claims23
An active clamp circuit comprising:
- an active clamp capacitor coupled in series with an active clamp switch;
- and
- an active clamp controller circuit to receive an active clamp switch current that passes through the active clamp switch and to control the active clamp switch based on the received active clamp switch current;
- wherein:
- the active clamp controller circuit is configured to enable the active clamp switch based on a first amplitude comparison, the first amplitude comparison being based on the active clamp switch current;
- and
- the active clamp controller circuit is configured to disable the active clamp switch based on a second amplitude comparison and a third amplitude comparison, the second amplitude comparison and the third amplitude comparison being based on the active clamp switch current.
An apparatus comprising:
- a power converter circuit to convert an input voltage from a voltage source to an output voltage, the power converter circuit comprising a transformer having a primary winding and a secondary winding, a first winding node of the primary winding being coupled to the voltage source to receive the input voltage;
- a main switch coupled to a second winding node of the primary winding to control a current through the primary winding;
- and
- an active clamp circuit to clamp a voltage at the second winding node of the primary winding, the active clamp circuit comprising:
- i) a series circuit combination of an active clamp capacitor coupled in series to an active clamp switch, the series circuit combination being coupled in parallel with the primary winding;
- and
- ii) an active clamp controller circuit to receive an active clamp switch current that passes through the active clamp switch and to control the active clamp switch based on the active clamp switch current;
- wherein:
- the active clamp controller circuit is configured to enable the active clamp switch based on a first amplitude comparison, the first amplitude comparison being based on the active clamp switch current;
- and
- the active clamp controller circuit is configured to disable the active clamp switch based on a second amplitude comparison and a third amplitude comparison, the second amplitude comparison and the third amplitude comparison being based on the active clamp switch current.
Dependencies are inferred from the claim text.