Isolated dual converter having primary side internal feedback for output regulation

Claim 2

A power converter, comprising: a pulse width modulated switching power converter having a power switch for regulating an internal voltage output; and an alternating current tank coupled to the internal voltage output, the alternating current tank having a storage capacitor and a transformer having a primary winding, a first switch that, when ON, couples the storage capacitor to the internal voltage output wherein the storage capacitor is charged and a first current flows in a first direction through the primary winding, a second switch that, when ON, permits the charged storage capacitor to discharge, wherein a second current flows in a second direction opposite to the first direction through the primary winding, and duty cycle control circuitry for alternately switching ON and OFF the first and second switches, the first switch being ON when the second switch is OFF and the second switch being ON when the first switch is OFF, the duty cycle control circuitry alternately switching the first and second switches at a constant duty cycle and such that the ON and OFF times of each switch are substantially equal, whereby a voltage produced across a secondary winding of the transformer is regulated by modulating the power switch.

Claim 3

The power converter of claim 1 , wherein the modulated switching power converter is a pulse width modulated boost power converter.

Claim 4

The power converter of claim 2 , wherein the storage capacitor is in series with the primary winding.

Claim 5

The power converter of claim 3 , wherein the storage capacitor is a resonant capacitor, the resonant capacitor and a leakage inductance of the primary winding forming a series resonant tank having a resonant frequency less than or equal to a period of the duty cycle control circuitry, whereby the first and second currents are each half-wave quasi-sinusoidal currents.

Claim 6

The power converter of claim 4 , wherein the voltage across the secondary winding is regulated by adjusting the pulse width modulation of the power switch in response to sensing a peak of the first and second currents.

Claim 7

The power converter of claim 5 , wherein the voltage across the secondary winding is further regulated by adjusting the pulse width modulation of the power switch in response to sensing the internal voltage output.

Claim 8

The power converter of claim 6 , wherein the voltage across the secondary winding is further regulated by adjusting the pulse width modulation of the power switch in response to sensing the voltage across the secondary winding through an isolator.

Claim 9

The power converter of claim 7 , wherein the isolator is an optoisolator.

Claim 10

The power converter of claim 2 , wherein the storage capacitor is a resonant capacitor in parallel with the primary winding, the resonant capacitor and a leakage inductance of the primary winding forming a parallel resonant tank having a resonant frequency less than or equal to a period of the duty cycle control circuitry, whereby when the first switch is ON, a first half-wave quasi-sinusoidal voltage is impressed across the primary winding, and when the second switch is ON, a second half-wave quasi-sinusoidal voltage is impressed across the primary winding, the second half-wave quasi-sinusoidal voltage being antipodal to the first half-wave quasi-sinusoidal voltage.

Claim 11

The power converter of claim 9 , wherein the voltage across the secondary winding is regulated by adjusting the pulse width modulation of the power switch in response to sensing the first and second currents.

Claim 12

The power converter of claim 1 , wherein the voltage across the secondary winding is further regulated by adjusting the pulse width modulation of the power switch in response to sensing the internal voltage output.

Claim 13

The power converter of claim 11 , wherein the voltage across the secondary winding is further regulated by adjusting the pulse width modulation of the power switch in response to sensing the voltage across the secondary winding through an isolator.

Claim 14

The power converter of claim 12 , wherein the isolator is an optoisolator.

Claim 15

The power converter of claim 1 , wherein the pulse width modulated switching power converter is a buck power converter.

Claim 16

The power converter of claim 14 , wherein the storage capacitor is in series wit h the primary winding.

Claim 17

The power converter of claim 15 , wherein the storage capacitor is a resonant capacitor, the resonant capacitor and a leakage inductance of the primary winding forming a series resonant tank having a resonant frequency less than or equal to a period of the duty cycle control circuitry, whereby the first and second currents are each half-wave quasi-sinusoidal currents.

Claim 18

The power converter of claim 16 , wherein the voltage across the secondary winding is regulated by adjusting the pulse width modulation of the power switch in response to sensing a peak of the first and second currents.

Claim 19

The power converter of claim 17 , wherein the voltage across the secondary winding is further regulated by adjusting the pulse width modulation of the power switch in response to sensing the internal voltage output.

Claim 20

The power converter of claim 18 , wherein the voltage across the secondary winding is further regulated by adjusting the pulse width modulation of the power switch in response to sensing the voltage across the secondary winding through an isolator.

Claim 21

The power converter of claim 19 wherein the isolator is an optoisolator.

Claim 22

The power converter of claim 14 , wherein the storage capacitor is a resonant capacitor in parallel with the primary winding, the resonant capacitor and a leakage inductance of the primary winding forming a parallel resonant tank having a resonant frequency less than or equal to a period of the duty cycle control circuitry, whereby when the first switch is ON, a first half-wave quasi-sinusoidal voltage is impressed across the primary winding, and when the second switch is ON, a second half-wave quasi-sinusoidal voltage is impressed across the primary winding, the second half-wave quasi-sinusoidal voltage being antipodal to the first half-wave quasi-sinusoidal voltage.

Claim 23

The power converter of claim 21 , wherein the voltage across the secondary winding is regulated by adjusting the pulse width modulation of the power switch in response to sensing the first and second currents.

Claim 24

The power converter of claim 22 , wherein the voltage across the secondary winding is further regulated by adjusting the pulse width modulation of the power switch in response to sensing the internal voltage output.

Claim 25

The power converter of claim 23 , wherein the voltage across the secondary winding is further regulated by adjusting the pulse width modulation of the power switch in response to sensing the voltage across the secondary winding through an isolator.

Claim 26

The power converter of claim 24 , wherein the isolator is an optoisolator.

Claim 27

A circuit for use in a power supply, comprising: a power switch coupled to a voltage input; a pulse width modulator for controlling a duty cycle of the power switch; a diode having its anode coupled to the voltage input; a first switch coupled to the cathode of the diode and to a voltage output; a second switch coupled to the voltage output; and control circuitry for alternately switching ON and OFF the first and second switches, the first switch being ON when the second switch is OFF and vice versa, the control circuitry alternately switching the first and second switches at a constant duty cycle, and such that the ON and OFF times of each switch are substantially equal, whereby a voltage produced across a secondary winding of the transformer is regulated by modulating the power switch.

Claim 28

A circuit for use in a power supply, comprising: a power switch coupled to a voltage input; a pulse width modulator for controlling a duty cycle of the power switch; a diode having its anode coupled to the voltage input; a first switch coupled to the cathode of the diode and to a voltage output; a second switch coupled to the voltage output; and control circuitry for alternately switching ON and OFF the first and second switches, the first switch being ON when the second switch is OFF and vice versa, the control circuitry alternately switching the first and second switches at a constant duty cycle, and such that the ON and OFF times of each switch are substantially equal, whereby a voltage produced across a secondary winding of the transformer is regulated by modulating the power switch.

Claim 29

The circuit of claim 26 , wherein the power switch, the diode, the pulse width modulator, the first switch, the second switch and the control circuitry are integrated on the circuit.

Claim 30

A power converter, comprising: a pulse width modulated switching power converter having a power switch for regulating an internal voltage output; a plurality of alternating current tanks coupled to the internal voltage output, each alternating current tank in the plurality of alternating current tanks having a storage capacitor and a transformer having a primary winding, a first switch that, when ON, couples the storage capacitor to the internal voltage output wherein the storage capacitor is charged and a first current flows in a first direction through the primary winding, a second switch that, when ON, permits the charged storage capacitor to discharge, wherein a second current flows in a second direction opposite to the first direction through the primary winding, and duty cycle control circuitry for alternately switching ON and OFF the first and second switches, the first switch being ON when the second switch is OFF and the second switch being ON when the first switch is OFF, the duty cycle control circuitry alternately switching the first and second switches at a constant duty cycle, and such that the ON and OFF times of each switch are substantially equal, whereby, whereby a voltage produced across a secondary winding of the transformer is regulated by modulating the power switch; and a clock coupled to the plurality of the alternating current tanks, wherein the first switches are switched synchronously with each other and the second switches are switched synchronously with each other.

Claim 31

A power converter, comprising: a pulse width modulated switching power converter having a power switch for regulating an internal voltage output; a plurality of alternating current tanks coupled to the internal voltage output, each alternating current tank in the plurality of alternating current tanks having a storage capacitor and a transformer having a primary winding, a first switch that, when ON, couples the storage capacitor to the internal voltage output wherein the storage capacitor is charged and a first current flows in a first direction through the primary winding, a second switch that, when ON, permits the charged storage capacitor to discharge, wherein a second current flows in a second direction opposite to the first direction through the primary winding, and duty cycle control circuitry for alternately switching ON and OFF the first and second switches, the first switch being ON when the second switch is OFF and the second switch being ON when the first switch is OFF, the duty cycle control circuitry alternately switching the first and second switches at a constant duty cycle, and such that the ON and OFF times of each switch are substantially equal, whereby, whereby a voltage produced across a secondary winding of the transformer is regulated by modulating the power switch; and a clock coupled to the plurality of the alternating current tanks, wherein the first switches are switched synchronously with each other and the second switches are switched synchronously with each other.

Claim 32

The power converter of claim 28 , wherein the modulated switching power converter is a boost power converter.

Claim 33

The power converter of claim 29 , wherein within each of the alternating current tanks, the storage capacitor is in series with the primary winding.

Claim 34

The power converter of claim 30 , wherein within each of the alternating current tanks, the storage capacitor is a resonant capacitor, the resonant capacitor and a leakage inductance of the primary winding forming a series resonant tank having a resonant frequency less than or equal to a period of the 50% duty cycle control circuitry, whereby the first and second currents are each half-wave quasi-sinusoidal currents.

Claim 35

The power converter of claim 29 , wherein within each of the alternating current tanks, the storage capacitor is a resonant capacitor in parallel with the primary winding, the resonant capacitor and a leakage inductance of the primary winding forming a parallel resonant tank having a resonant frequency less than or equal to a period of the 50% duty cycle control circuitry, whereby when the first switch is ON, a first half-wave quasi-sinusoidal voltage is impressed across the primary winding, and when the second switch is ON, a second half-wave quasi-sinusoidal voltage is impressed across the primary winding, the second half-wave quasi-sinusoidal voltage being antipodal to the first half-wave quasi-sinusoidal voltage.

Claim 36

The power converter of claim 28 , wherein the modulated switching power converter is a pulse width modulated buck power converter.

Claim 37

The power converter of claim 33 , wherein within each of the alternating current tanks, the storage capacitor is in series with the primary winding.

Claim 38

The power converter of claim 34 , wherein within each of the alternating current tanks, the storage capacitor is a resonant capacitor, the resonant capacitor and a leakage inductance of the primary winding forming a series resonant tank having a resonant frequency less than or equal to a period of the 50% duty cycle control circuitry, whereby the first and second currents are each half-wave quasi-sinusoidal currents.

Claim 39

The power converter of claim 33 , wherein within each of the alternating current tanks, the storage capacitor is a resonant capacitor in parallel with the primary winding, the resonant capacitor and a leakage inductance of the primary winding forming a parallel resonant tank having a resonant frequency less than or equal to a period of the 50% duty cycle control circuitry, whereby when the first switch is ON, a first half-wave quasi-sinusoidal voltage is impressed across the primary winding, and when the second switch is ON, a second half-wave quasi-sinusoidal voltage is impressed across the primary winding, the second half-wave quasi-sinusoidal voltage being antipodal to the first half-wave quasi-sinusoidal voltage.

Claim 40

A power converter, comprising: a first circuit stage including a modulated switching power converter having a power switch for regulating an internal voltage output; and a second circuit stage including an alternating current tank coupled to the internal voltage output, the alternating current tank having a storage capacitor and a transformer having a primary winding, a first switch that, when ON, couples the storage capacitor to the internal voltage output wherein the storage capacitor is charged and a first current flows in a first direction through the primary winding, a second switch that, when ON, permits the charged storage capacitor to discharge, wherein a second current flows in a second direction opposite to the first direction through the primary winding, and duty cycle control circuitry for alternately switching ON and OFF the first and second switches, the first switch being ON when the second switch is OFF and the second switch being ON when the first switch is OFF, the duty cycle control circuitry alternately switching the first and second switches it a constant duty cycle, and such that the ON and OFF times of each switch are substantially equal, whereby a voltage produced across a secondary winding of the transformer is regulated by modulating the power switch.

Claim 41

A power converter, comprising: a first circuit stage including a modulated switching power converter having a power switch for regulating an internal voltage output; and a second circuit stage including an alternating current tank coupled to the internal voltage output, the alternating current tank having a storage capacitor and a transformer having a primary winding, a first switch that, when ON, couples the storage capacitor to the internal voltage output wherein the storage capacitor is charged and a first current flows in a first direction through the primary winding, a second switch that, when ON, permits the charged storage capacitor to discharge, wherein a second current flows in a second direction opposite to the first direction through the primary winding, and duty cycle control circuitry for alternately switching ON and OFF the first and second switches, the first switch being ON when the second switch is OFF and the second switch being ON when the first switch is OFF, the duty cycle control circuitry alternately switching the first and second switches it a constant duty cycle, and such that the ON and OFF times of each switch are substantially equal, whereby a voltage produced across a secondary winding of the transformer is regulated by modulating the power switch.

Claim 42

A circuit for use in a power supply, comprising a first circuitry stage including: a power switch coupled to a voltage input; a pulse width modulator for controlling a duty cycle of the power switch; a diode having its anode coupled to the voltage input; and a second circuitry stage coupled to the first circuitry stage, said second circuitry stage including: a first switch coupled to the cathode of the diode and to a voltage output; a second switch coupled to the voltage output; and control circuitry for alternately switching ON and OFF the first and second switches, the first switch being ON when the second switch is OFF and vice versa, the control circuitry alternately switching the first and second switches at a constant duty cycle, and such that the ON and OFF times of each switch are substantially equal, whereby a voltage produced across a secondary winding of the transformer is regulated by modulating the power switch.

Claim 43

A circuit for use in a power supply, comprising a first circuitry stage including: a power switch coupled to a voltage input; a pulse width modulator for controlling a duty cycle of the power switch; a diode having its anode coupled to the voltage input; and a second circuitry stage coupled to the first circuitry stage, said second circuitry stage including: a first switch coupled to the cathode of the diode and to a voltage output; a second switch coupled to the voltage output; and control circuitry for alternately switching ON and OFF the first and second switches, the first switch being ON when the second switch is OFF and vice versa, the control circuitry alternately switching the first and second switches at a constant duty cycle, and such that the ON and OFF times of each switch are substantially equal, whereby a voltage produced across a secondary winding of the transformer is regulated by modulating the power switch.

Claim 44

A power converter, comprising: a first circuitry stage including a modulated switching power converter having a power switch for regulating an internal voltage output; a second circuitry stage including a plurality of alternating current tanks coupled to the internal voltage output, each alternating current tank in the plurality of alternating current tanks having a storage capacitor and a transformer having a primary winding, a first switch that, when ON, couples the storage capacitor to the internal voltage output wherein the storage capacitor is charged and a first current flows in a first direction through the primary winding, a second switch that, when ON, permits the charged storage capacitor to discharge, wherein a second current flows in a second direction opposite to the first direction through the primary winding, and duty cycle control circuitry for alternately switching ON and OFF the first and second switches, the first switch being ON when the second switch is OFF and the second switch being ON when the first switch is OFF, the duty cycle control circuitry alternately switching the first and second switches at a constant duty cycle, and such that the ON and OFF times of each switch are substantially equal, whereby a voltage produced across a secondary winding of the transformer is regulated by modulating the power switch; and a clock circuit coupled to the plurality of the alternating current tanks, wherein the first switches are switched synchronously with each other and the second switches are switched synchronously with each other.

Claim 45

A power converter, comprising: a first circuitry stage including a modulated switching power converter having a power switch for regulating an internal voltage output; a second circuitry stage including a plurality of alternating current tanks coupled to the internal voltage output, each alternating current tank in the plurality of alternating current tanks having a storage capacitor and a transformer having a primary winding, a first switch that, when ON, couples the storage capacitor to the internal voltage output wherein the storage capacitor is charged and a first current flows in a first direction through the primary winding, a second switch that, when ON, permits the charged storage capacitor to discharge, wherein a second current flows in a second direction opposite to the first direction through the primary winding, and duty cycle control circuitry for alternately switching ON and OFF the first and second switches, the first switch being ON when the second switch is OFF and the second switch being ON when the first switch is OFF, the duty cycle control circuitry alternately switching the first and second switches at a constant duty cycle, and such that the ON and OFF times of each switch are substantially equal, whereby a voltage produced across a secondary winding of the transformer is regulated by modulating the power switch; and a clock circuit coupled to the plurality of the alternating current tanks, wherein the first switches are switched synchronously with each other and the second switches are switched synchronously with each other.

Claim 46

A dual stage power converter, comprising: a first stage modulated switching power converter having a regulated output; and a second stage alternating current tank coupled to said output of said first stage, said second stage having a first switch and second switch that are actuated by alternately switching ON and OFF the first and second switches, the first switch being ON at approximately the same time the second switch is OFF and vice versa, and said first and second switches being actuated at a constant duty cycle.

Claim 47

A dual stage power converter, comprising: a first stage modulated switching power converter having a regulated output; and a second stage alternating current tank coupled to said output of said first stage, said second stage having a first switch and second switch that are actuated by alternately switching ON and OFF the first and second switches, the first switch being ON at approximately the same time the second switch is OFF and vice versa, and said first and second switches being actuated at a constant duty cycle.