Factorized power architecture with point of load sine amplitude converters

A method of converting power from an input source for delivery to a load, where the load may vary over a normal operating range, comprising:

• providing a transformer;
• forming a resonant circuit including the transformer and having a characteristic resonant frequency and period;
• providing output circuitry connected to the transformer for delivering a rectified output voltage to the load;
• providing two or more primary switches to drive the resonant circuit;
• and
• providing a switch controller to operate the primary switches in a series of converter operating cycles, each converter operating cycle characterized by
• (a) two power transfer intervals of essentially equal duration, during which one or more of the primary switches are ON and power is transferred from the input to the output via the transformer;
• and
• (b) two energy-recycling intervals each having an essentially constant duration over the normal operating range during which the primary switches are OFF;
• and
• using the switch controller to turn the primary switches OFF essentially at times when the current in a secondary winding returns to zero;
• and
• using magnetizing current to charge and discharge capacitances during the energy-recycling intervals.

A method of converting power from an input source for delivery to a load, where the load may vary over a normal operating range, in a converter having two or more primary switches connected to drive a resonant circuit including a transformer and having a characteristic resonant frequency and period, output circuitry connected to the transformer for delivering a rectified output voltage to the load, and a switch controller to operate the switches, the method comprising:

• operating the switches in a series of converter operating cycles, each converter operating cycle characterized by:
• (a) first and second power transfer intervals during which one or more of the primary switches are ON, power is transferred from the input source to the load via the transformer, and voltages and currents in the converter rise and fall at the characteristic resonant frequency of the resonant circuit;
• the first and second power transfer intervals being of substantially equal duration;
• and
• (b) two energy-recycling intervals during which the primary switches are OFF;
• wherein the switch controller turns the primary switches OFF at times essentially when the current in a secondary winding returns to zero;
• and
• wherein currents in the converter are used to charge and discharge capacitances in the converter during the energy-recycling intervals;
• and
• providing an essentially constant voltage gain K=Vout/Vin at a load current for the power conversion, where Vin is the input source voltage and Vout is the rectified output voltage across the load.

A method of converting power from an input source for delivery to a load, where the load may vary over a normal operating range, in a converter having two or more primary switches connected to drive a resonant circuit including a transformer and having a characteristic resonant frequency and period, output circuitry connected to the transformer for delivering a rectified output voltage, and a switch controller to operate the switches, the method comprising:

• operating the primary switches in a series of converter operating cycles, each converter operating cycle being characterized by:
• (a) first and second power transfer intervals during which one or more of the primary switches are ON, power is transferred from the source to the load via the transformer, and voltages and currents in the converter rise and fall at the characteristic resonant frequency of the resonant circuit;
• the first and second power transfer intervals being of substantially equal duration over the normal operating range;
• and
• (b) two energy-recycling intervals during which the primary switches are OFF;
• and
• (c) a period having an essentially constant duration over the normal operating range;
• and
• using magnetizing current to charge and discharge capacitances during the energy-recycling intervals.

Apparatus for converting power from an input source for delivery to a load, where the load may vary over a normal operating range, comprising:

• a transformer;
• a resonant circuit including the transformer having a Q less than 13 and having a characteristic resonant frequency and period;
• output circuitry connected to the transformer for delivering a rectified output voltage to the load;
• two or more primary switches connected to drive the resonant circuit;
• a switch controller adapted to operate the primary switches in a series of converter operating cycles, each converter operating cycle characterized by two power transfer intervals of essentially equal duration each interval having a duration less than the characteristic resonant period, during which one or more of the primary switches are ON and power is transferred from the input to the output via the transformer;
• and
• a conversion efficiency from the source to the load having a peak greater than 90% within the normal operating range.

Apparatus for converting power from an input source for delivery to a load, where the load may vary over a normal operating range, comprising:

• a transformer;
• a resonant circuit including the transformer and having a characteristic resonant frequency and period;
• output circuitry connected to the transformer for delivering a rectified output voltage to the load;
• two or more primary switches connected to drive the resonant circuit;
• and
• a switch controller adapted to operate the primary switches in a series of converter operating cycles, each converter operating cycle characterized by
• (a) two power transfer intervals of essentially equal duration, during which one or more of the primary switches are ON and power is transferred from the input to the output via the transformer;
• and
• (b) two energy-recycling intervals each having an essentially constant duration over the normal operating range during which the primary switches are OFF;
• wherein the switch controller is adapted to turn the primary switches OFF essentially at times when the current in a secondary winding returns to zero;
• and
• magnetizing current is used to charge and discharge capacitances during the energy-recycling intervals.

Apparatus for converting power from an input source for delivery to a load, where the load may vary over a normal operating range, comprising:

• a transformer;
• a resonant circuit including the transformer and having a characteristic resonant frequency and period;
• output circuitry connected to the transformer for delivering a rectified output voltage to the load;
• two or more primary switches connected to drive the resonant circuit;
• and
• a switch controller adapted to operate the primary switches in a series of converter operating cycles, each converter operating cycle characterized by
• (a) first and second power transfer intervals during which one or more of the primary switches are ON, power is transferred from the source to the load via the transformer, and voltages and currents in the converter rise and fall at the characteristic resonant frequency;
• the first and second power transfer intervals being of substantially equal duration over the normal operating range;
• and
• (b) two energy-recycling intervals during which the primary switches are OFF;
• and
• (c) a period having an essentially constant duration over the normal operating range;
• and
• an essentially constant voltage gain K=Vout/Vin at a load current for the power conversion, where Vin is the input source voltage and Vout is the rectified output voltage;
• and
• wherein magnetizing current is used to charge and discharge capacitances during the energy-recycling intervals.

A method of distributing power from an input source to a load, where the load may vary over a normal operating range, comprising:

• using a first regulator at a first location to convert power from the input source at a source voltage, Vsource, and deliver a controlled DC voltage, Vf, to a factorized bus;
• using the factorized bus to carry power from the first regulator to a remote location separated by a distance from the first location;
• using a voltage transformation module (“VTM”) at the remote location to convert power, via a transformer, from the factorized bus at an input voltage Vin, essentially equal to the voltage delivered to the bus, Vf, to a DC output voltage, Vout;
• and
• using in the VTM an essentially constant voltage gain, K=Vout/Vin, at a load current;
• wherein the VTM has an output resistance, Rout;
• and
• wherein the load is supplied with a voltage, Vload, essentially equal to the output voltage of the VTM, Vout, which is regulated by the first regulator using the factorized bus.

A method of distributing power from an input source to a load, where the load may vary over a normal operating range, comprising:

• using a first regulator at a first location to convert power from the input source at a source voltage, Vsource, and deliver a controlled DC voltage, Vf, to a factorized bus;
• using the factorized bus to carry power from the first regulator to a remote location separated by a distance from the first location;
• using a voltage transformation module (“VTM”) at the remote location to convert power from the factorized bus and deliver a load voltage, Vload, the VTM having an input for receiving an input voltage, Vin, essentially equal to the voltage delivered to the bus, Vf, and an output for delivering an output voltage, Vout, essentially equal to the load voltage, Vload, and an output resistance, Rout;
• using a transformer in the power train of the VTM;
• using in the VTM an essentially constant voltage gain, K=Vout/Vin, at a load current;
• the VTM having two or more power switches and using a power conversion duty cycle greater than 80%.

A method of distributing power from an input source to a load, where the load may vary over a normal operating range, comprising:

• using a first regulator at a first location to convert power from the input source at a source voltage, Vsource, and deliver a controlled DC voltage, Vf, to a factorized bus;
• using the factorized bus to carry power from the first regulator to a remote location separated by a distance from the first location;
• using a voltage transformation module (“VTM”) at the remote location to convert power from the factorized bus and deliver a load voltage, Vload, the VTM having two or more primary switches connected to drive a transformer, an input for receiving an input voltage, Vin, essentially equal to the bus voltage, Vf, and an output for delivering an output voltage, Vout, essentially equal to the load voltage, Vload;
• and
• operating the primary switches in a series of converter operating cycles, each converter operating cycle characterized by
• (a) two power transfer intervals of essentially equal duration, during which one or more of the primary switches are ON and power is transferred from the input to the output via the transformer, and
• (b) two energy-recycling intervals during which the primary switches are OFF;
• wherein the load voltage, Vload, is regulated by the first regulator using the factorized bus.

A method of providing a power density greater than 200 Watts/cubic-inch in point-of-load converters for efficiently supplying a regulated DC voltage, Vload, to a load, where the load may vary over a normal operating range, from an input source, the method comprising:

• factorizing away from the point-of-load a power-conversion function of voltage regulation by using a first regulator to convert power from the input source to a controlled voltage, Vf, delivered to a factorized bus;
• localizing at the point-of-load a function of DC voltage transformation by converting the factorized bus voltage at the point-of-load, Vin, to an output voltage, Vout, essentially equal to Vload, with a voltage transformation module (“VTM”);
• adapting the VTM to operate at or above 500 KHz, to convert power via a transformer, and to provide an essentially constant DC voltage gain, K=Vout/Vin, at a load current, and
• regulating the load voltage, Vload, by controlling the voltage of the factorized bus, Vf.

A method for providing scalable electric power conversion capability in which power is converted from an input source and delivered to a load at a regulated DC output voltage, where the load may vary over a normal operating range, the method comprising:

• using a first regulator to convert power from the input source at a source voltage, Vsource, to a controlled DC voltage, Vf, delivered to a factorized bus;
• operating two or more voltage transformation modules (“VTMs), each comprising a transformer and an output resistance Rout, in parallel to convert power, via the transformers, from an input voltage, Vin, essentially equal to the factorized bus voltage, Vf, to a DC output voltage, Vout;
• using an essentially constant voltage gain, K=Vout/Vin, at a load current, in each of the VTMs;
• wherein the power provided to the load is shared in inverse proportion to the output resistance by each of the VTMs;
• and
• the output voltage provided to the load, Vload, is essentially equal to the output voltage of each of the VTMs, Vout, and is regulated by the first regulator using the factorized bus.

Apparatus for distributing power from an input source to a load, where the load may vary over a normal operating range, comprising:

• a first regulator at a first location having a first input and a first output, the first regulator having circuitry adapted to convert power from the input source at a source voltage, Vsource, and deliver a controlled DC voltage, Vf, to the first output;
• a factorized bus connected to the first output of the first regulator and extending to a remote location separated by a distance from the first location;
• a voltage transformation module (“VTM”) at the remote location having circuitry, including a transformer, adapted to convert power from an input voltage, Vin, essentially equal to the voltage delivered to the bus, Vf, to a DC output voltage, Vout;
• the VTM having an essentially constant voltage gain, K=Vout/Vin, at a load current and having an output resistance, Rout;
• wherein the load is supplied with a voltage, Vload, essentially equal to the output voltage, Vout, and regulated by the first regulator using the factorized bus.

Apparatus for distributing power from an input source to a load, where the load may vary over a normal operating range, comprising:

• a first regulator at a first location having a first input and a first output, the first regulator having circuitry adapted to convert power from the input source at a source voltage, Vsource, and deliver a controlled DC voltage, Vf, to the first output;
• a factorized bus connected to the first output of the first regulator and extending to a remote location separated by a distance from the first location;
• a voltage transformation module (“VTM”) at the remote location having circuitry, including a transformer, adapted to convert power from the factorized bus and deliver a load voltage, Vload, the VTM having an input for receiving an input voltage, Vin, essentially equal to the voltage delivered to the bus, an output for delivering an output voltage, Vout, essentially equal to the load voltage, Vload, an essentially constant voltage gain, K=Vout/Vin, at a load current, and an output resistance, Rout;
• the VTM further comprising two or more power switches and a power conversion duty cycle greater than 80% over the normal operating range.

Apparatus for distributing power from an input source to a load, where the load may vary over a normal operating range, comprising:

• a first regulator at a first location having a first input and a first output, the first regulator having circuitry adapted to convert power from the input source at a source voltage, Vsource, and deliver a controlled DC voltage, Vf, to the first output;
• a factorized bus connected to the first output of the first regulator and extending to a remote location separated by a distance from the first location;
• a voltage transformation module (“VTM”) at the remote location and having an input for receiving a DC input voltage, Vin, essentially equal to the voltage delivered to the bus, Vf, two or more primary switches connected to drive a transformer with power received from the input, an output for delivering a DC output voltage, Vout, an output resistance, Rout, and a switch controller adapted to operate the primary switches in a series of converter operating cycles, each converter operating cycle characterized by
• (a) two power transfer intervals of essentially equal duration, during which one or more of the primary switches are ON and power is transferred from the input to the output via the transformer,
• (b) two energy-recycling intervals during which the primary switches are OFF;
• wherein the load is supplied with a voltage, Vload, essentially equal to the output voltage, Vout, and regulated by the first regulator using the factorized bus.

Apparatus for converting power at a point-of-load from a factorized bus driven by a source of controlled DC voltage, Vf, for delivering a regulated DC voltage, Vload, to a load where the load may vary over a normal operating range, the apparatus comprising:

• a voltage transformation module (“VTM”) having an enclosure for housing power conversion circuitry, an input terminal, and an output terminal;
• the power conversion circuitry comprising:
• an input connected to the input terminal and adapted to receive a DC input voltage, Vin, essentially equal to Vf;
• an output connected to the output terminal and adapted to deliver a DC output voltage, Vout, essentially equal to Vload;
• a transformer;
• two or more primary switches connected to drive the transformer with power received from the input;
• and
• a controller adapted to operate the primary switches in a series of converter operating cycles, each converter operating cycle characterized by
• (a) two power transfer intervals of essentially equal duration during which one or more of the primary switches are ON and power is transferred from the input to the output via the transformer,
• (b) two energy-recycling intervals during which the primary switches are OFF;
• and
• (c) a period less than 2 micro seconds;
• wherein the VTM has a power density greater than 250 Watts/cubic-inch, an essentially constant DC voltage gain, K=Vout/Vin, at a load current, and an output resistance, Rout, and regulates the load voltage, Vload, as a fraction, K, of the factorized bus voltage, Vf.

Apparatus for providing scalable electric power conversion capability in which power is converted from a factorized bus driven by a voltage source of controlled DC voltage, Vf, and delivered to a load at a regulated DC output voltage, Vload, where the load may vary over a normal operating range, the apparatus comprising:

• two or more voltage transformation modules (“VTMs”) connected in parallel, each VTM having
• (a) an input adapted to receive a DC input voltage, Vin, essentially equal to Vf;
• (b) an output adapted to deliver an output voltage, Vout, essentially equal to Vload;
• (c) a transformer;
• (d) two or more primary switches connected to drive the transformer with power received from the input;
• and
• (e) a controller operating the primary switches in a series of converter operating cycles;
• (f) an essentially constant voltage gain K=Vout/Vin at a load current;
• and
• (g) an output resistance, Rout;
• wherein the power delivered to the load is shared by each VTM in inverse proportion to the output resistance of each VTM;
• and
• the output voltage supplied to the load, Vload, is essentially equal to the output voltage, Vout, of each of the VTMs and is regulated by the factorized bus voltage Vf.

Apparatus comprising:

• an electronic assembly having
• a VTM having an input connected to receive power from a factorized bus at a voltage V1 and an output for delivering power at a second voltage, V2, where V1 is not equal to V2;
• and
• electronic circuitry, requiring power at levels which may vary over a normal operating range and at the second voltage, V2;
• and wherein
• a power regulator supplies power at a controlled voltage to the VTM;
• the VTM is packaged separately from the power regulator;
• and
• the VTM has a transformer and is adapted to convert power from the input voltage V1 and deliver the second voltage, V2, at an essentially constant voltage gain, K=V2/V1, at a load current, and with an output resistance, Rout.

A method comprising:

• providing a VTM having a package, an input adapted to receive power from a source external to the package at a DC input voltage Vin, an output adapted to deliver power to a load external to the package at a DC output voltage, Vout, and a transformer;
• the VTM being adapted to convert power from the input voltage Vin and deliver the output voltage, Vout, at an essentially constant voltage gain, K=Vout/Vin, at a load current, and with an output resistance, Rout;
• connecting the input of the VTM to a regulated source;
• and
• connecting the output of the VTM to electronic circuitry.

Apparatus for converting power from an input source to a load, comprising:

• a circuit board having a plurality of conductive layers,
• a transformer having a permeable core comprising a plurality of core elements, each core element passing through a hole in the circuit board, and primary and secondary windings formed by respective patterns on a plurality of conductive layers of the circuit board and around a plurality of core elements;
• a series resonant circuit including the transformer and having a characteristic resonant frequency;
• two or more primary switches connected to drive the resonant circuit;
• and
• output circuitry connected to the transformer for delivering a rectified output voltage.

An apparatus for driving a control input of one or more power switching devices, comprising:

• a drive transformer having a secondary winding;
• a plurality of switches each having a control terminal referenced to a common signal reference for turning the switch ON and OFF and an output connected to drive the transformer;
• the plurality of switches including a first switch and a second switch being respectively poled to induce a magnetic flux in the drive transformer in a first and in a second direction when ON;
• the secondary winding being connected to drive the control inputs of the one or more power switching devices;
• a control circuit connected to the control terminals and configured to operate the first and second switches in a series of control cycles each characterized by:
• (a) two ON intervals during which one of the first and second switches is ON;
• (b) two OFF intervals during which both of the first and second switches is OFF and energy stored in the drive transformer is used to charge and discharge parasitic output capacitances of the plurality of switches and a parasitic input capacitance of the one or more power switching devices.

A method for driving a control input of one or more power switching devices, comprising:

• using a secondary winding of a drive transformer to drive the control inputs of the one or more power switching devices;
• using a plurality of switches to drive the drive transformer;
• connecting a control terminal of each switch to reference a common signal reference for turning the switch ON and OFF,
• using a first switch and a second switch in the plurality of switches to respectively induce a magnetic flux in the drive transformer in a first and in a second direction when ON;
• operating the first and second switches in a series of control cycles each characterized by:
• (a) two ON intervals during which one of the first and second switches is ON;
• (b) two OFF intervals during which both of the first and second switches is OFF and energy stored in the drive transformer is used to charge and discharge parasitic output capacitances of the plurality of switches and a parasitic input capacitance of the one or more power switching devices.

A method of converting power from an input source for delivery to a load, where the load may vary over a normal operating range, comprising:

• providing a transformer;
• forming a resonant circuit including the transformer and having a characteristic resonant frequency and period;
• providing output circuitry connected to the transformer for delivering a rectified output voltage to the load;
• providing a first pair of primary switches connected in series and a second pair of primary switches connected in series, the first and second pairs connected to drive the resonant circuit;
• and
• providing a switch controller to operate the first and second pair of primary switches out of phase in a series of converter operating cycles;
• and
• arranging the resonant circuit and primary switches symmetrically to reduce common-mode noise.

A method of converting power from an input source for delivery to a load, where the load may vary over a normal operating range, comprising:

• providing a transformer;
• forming a resonant circuit including the transformer and having a characteristic resonant frequency and period and having a Q less than 13;
• providing output circuitry connected to the transformer for delivering a rectified output voltage to the load;
• providing a primary switch connected to drive the resonant circuit;
• providing a switch controller to operate the primary switch in a series of converter operating cycles;
• and
• providing a conversion efficiency from the source to the load having a peak greater than 90% within the normal operating range.

A method of making a power converter comprising:

• providing resonant inductance comprising the leakage inductance of a transformer for use in a resonant circuit in the converter;
• measuring the resonant inductance;
• selecting a resonant capacitor based upon the measured resonant inductance to achieve a desired resonant frequency for the resonant circuit;
• assembling the converter using the resonant inductance and the selected capacitor.

A method of making a power converter comprising:

• providing resonant inductance comprising the leakage inductance of a transformer for use in a resonant circuit in the converter;
• measuring the resonant inductance;
• selecting an incremental resonant inductor based upon the measured resonant inductance to achieve a desired total resonant inductance for the resonant circuit;
• assembling the converter using the resonant inductance and the selected incremental resonant inductor.

Apparatus for converting power from an input source for delivery to a load comprising:

• a transformer;
• a primary switch connected to drive the transformer;
• output circuitry connected to the transformer for delivering an output voltage to the load;
• a switch controller adapted to operate the primary switches in a series of converter operating cycles;
• and
• modulation control circuitry adapted to modulate the ON-resistance of the primary switch.

The apparatus of 170 further comprising:

• a resonant circuit including the transformer having a Q less than 13 and having a characteristic resonant frequency and period;
• wherein the primary switch comprises two or more primary switches connected to drive the resonant circuit;
• wherein the output voltage is rectified;
• wherein the load may vary over a normal operating range;
• and
• wherein each converter operating cycle is characterized by two power transfer intervals of essentially equal duration each interval having a duration less than the characteristic resonant period, during which one or more of the primary switches are ON and power is transferred from the input to the output via the transformer;
• and
• comprising a conversion efficiency from the source to the load having a peak greater than 90% within the normal operating range.

A method for converting power from an input source for delivery to a load comprising:

• providing a transformer;
• providing a primary switch to drive the transformer;
• providing output circuitry connected to the transformer for delivering an output voltage to the load;
• providing a switch controller adapted to operate the primary switch in a series of converter operating cycles;
• providing modulation control circuitry adapted to modulate the ON-resistance of the primary switch.

Apparatus for delivering a unipolar control voltage comprising:

• a transformer having a primary winding, a secondary winding, and a magnetizing inductance;
• drive circuitry connected to drive the primary winding to produce a bipolar voltage across the secondary winding;
• a first output terminal and a reference terminal for delivering the control voltage;
• switch circuitry connected to the secondary winding and adapted to:
• (a) connect the secondary winding across the first output terminal and the reference terminal when a voltage across the secondary winding is of a first polarity;
• (b) clamp the first output terminal to the reference terminal when a voltage across the secondary winding is of a second polarity;
• and
• (c) enable recycling of energy between the magnetizing inductance of the transformer and the parasitic capacitances of the switch circuitry and the capacitance between the first output terminal and the reference terminal.

A method for delivering a unipolar control voltage comprising:

• providing a transformer having a primary winding, a secondary winding, and a magnetizing inductance;
• providing drive circuitry to drive the primary winding to produce a bipolar voltage across the secondary winding;
• providing a first output terminal and a reference terminal for delivering the control voltage;
• providing switch circuitry connected to the secondary winding and adapted to:
• (a) connect the secondary winding across the first output terminal and the reference terminal when a voltage across the secondary winding is of a first polarity;
• (b) clamp the first output terminal to the reference terminal when a voltage across the secondary winding is of a second polarity;
• and
• (c) enable recycling of energy between the magnetizing inductance of the transformer and the parasitic capacitances of the switch circuitry and the capacitance between the first output terminal and the reference terminal.

A method for delivering a unipolar control voltage across a first output terminal and a reference terminal in a circuit using switch circuitry and a transformer having a primary, a secondary winding, and a magnetizing inductance, the method comprising:

• driving the primary winding to produce a bipolar voltage across the secondary winding;
• connecting the secondary winding across the first output terminal and the reference terminal when a voltage across the secondary winding is of a first polarity;
• clamping the first output terminal to the reference terminal when a voltage across the secondary winding is of a second polarity;
• and
• recycling energy between the magnetizing inductance of the transformer and parasitic capacitances of the switch circuitry and between the first output terminal and the reference terminal.

Apparatus comprising:

• a first integrated semiconductor device formed on a common die and comprising a plurality of FETs each having a gate, a source, and a drain, and having the same threshold voltage;
• the first integrated semiconductor device having a first switch section and a first clamp section, the first switch section comprising one or more of the plurality of FETs connected in parallel, and the first clamp section comprising one or more of the plurality of FETs;
• first circuitry connected to the first switch section of the first integrated semiconductor device;
• second circuitry connected to the first clamp section of the first integrated semiconductor device, the second circuitry being configured to be clamped when the clamp section is ON;
• the gates of the one or more of the plurality of FETs in the first switch section and first clamp section being connected to a first gate terminal;
• the sources of the one or more of the plurality of FETs in the first switch section and first clamp section being connected to a first source terminal;
• wherein the clamp section clamps the second circuitry in response to turning ON of the switch section.