Transformer coupled power switch demodulator

Claim 2

A power demodulator for controlling the power delivered to a load from a source of direct current in accordance with a returnto-zero pulse width modulated input signal comprising first and second power transistors having their emitter and collector electrodes connected together and in series with said source and said load, a current transformer sized for the carrier frequency of said input signal and having a primary winding for connection with said input signal, and first and second secondary windings connected Across the emitter and base electrodes of said first and second power transistors respectively, whereby said first and second power transistors are alternately rendered conductive at the carrier frequency of said input signal and the power delivered to the load is proportional to the degree of modulation of said input signal.

Claim 3

A power demodulator comprising a transformer including a primary winding and first and second secondary windings, means for applying a return-to-zero pulse width modulated input signal to said primary winding, said transformer being sized for the carrier frequency of said input signal, first and second power transistors having their respective emitters and collectors connected together, said first secondary windings being connected with the base and emitter electrodes of said first power transistor, said second secondary winding being connected with the base and emitter electrodes of said second power transistor, a direct current source connected with the collector electrodes of said first and second power transistors and a load connected with the emitter electrodes of said first and second power transistors, whereby said first and second transistors are respectively rendered conductive during the positive and negative on-times of said input signal and are nonconductive during the off-time of said input signal.

Claim 4

A power demodulator comprising a transformer including a primary winding and first and second secondary windings, means for applying a return-to-zero pulse width modulated input signal to said primary winding, said transformer being sized for the carrier frequency of said input signal, first and second power transistors having their respective emitters and collectors connected together, said first secondary windings being connected with the base and emitter electrodes of said first power transistor, said second secondary winding being connected with the base and emitter electrodes of said second power transistor, a direct current source connected with the collector electrodes of said first and second power transistors and a load connected with the emitter electrodes of said first and second power transistors, whereby said first and second transistors are respectively rendered conductive during the positive and negative on-times of said input signal and are nonconductive during the off-time of said input signal.

Claim 5

A power demodulator comprising a transformer including a primary winding for connection with a return-to-zero pulse width modulated input signal, said transformer being sized for the carrier frequency of said input signal, first and second power transistors having their respective emitters and collectors connected together, said transformer further including first, second, third, and fourth secondary windings, said first and second secondary windings being respectively connected across the base and emitter electrodes of said first and second power transistors, a first clamp diode connected in series with said third secondary winding across the base and collector electrodes of said first power transistor to prevent saturation of said first power transistor, a second clamp diode connected in series with said fourth secondary windings across the base and collector electrodes of said second power transistor to prevent saturation of said second power transistor, means for connecting a source of direct current to a load through the emitter-collector electrodes of said first and second power transistors, whereby said first and second transistors are respectively rendered conductive during the positive and negative portions of each cycle of said input signal.

Claim 6

A power demodulator comprising a transformer including a primary winding for connection with a return-to-zero pulse width modulated input signal, said transformer being sized for the carrier frequency of said input signal, first and second power transistors having their respective emitters and collectors connected together, said transformer further including first, second, third, and fourth secondary windings, said first and second secondary windings being respectively connected across the base and emitter electrodes of said first and second power transistors, a first clamp diode connected in series with said third secondary winding across the base and collector electrodes of said first power transistor to prevent saturation of said first power transistor, a second clamp diode connected in series with said fourth secondary windings across the base and collector electrodes of said second power transistor to prevent saturation of said second power transistor, means for connecting a source of direct current to a load through the emitter-collector electrodes of said first and second power transistors, whereby said first and second transistors are respectively rendered conductive during the positive and negative portions of each cycle of said input signal.