Texas Instruments Corporation

Bharath Balaji Kannan

Richard Lee Valley

Bing Lu

Robert Allan Neidorff

Joseph Maurice Khayat

Ashish Khandelwal

Pei-Hsin Liu

Yipeng Su

Seetharaman Sridhar

Filippo Marino

Salvatore Giombanco

Sunglyong Kim

Jose Antonio Vieira Formenti

Tobin D Hagan

Robert Martinez

Michael Ryan Hanschke

Michael Corry

Victor Samuel Sinow

Hong Huang

A DC-to-DC converter having primary- and secondary-side circuitry separated by an isolation barrier, with a transformer and a feedback lane across the barrier, uses a dynamic function current source in its secondary-side circuitry to dynamically adjust the hysteresis threshold only at the transformer burst turn-off edge to provide enhanced immunity to transformer switching noise. An output voltage of the converter (or signal based thereon) is compared to the threshold to provide an input to a timing pulse generator that closes a switch to couple the dynamic function current source into voltage threshold setting circuitry. The dynamic function current source can reduce the threshold to a level that avoids chattering in transformer burst turn-off feedback signal caused by the noise, for a duration that can be based on lane delay of the converter and to an amplitude that can be based on the expected maximum negative amplitude of the noise.

Isolated high-voltage DC-DC converter hysteretic burst mode noise immunity using dynamic hysteresis

A system includes an isolated converter having a power transformer with a primary winding, a secondary winding, and an auxiliary winding. The system also includes: 1) a first switch coupled to the primary winding; 2) a switch controller coupled to the first switch; and 3) a bias power regulator circuit coupled to the auxiliary winding and the switch controller. The bias power regulator circuit includes a second switch. The bias power regulator circuit is configured to provide a bias supply output voltage to the switch controller based on a first set of modes that modulate a switching frequency of the second switch and based on a second mode in which the second switch stays off.

Bias power regulator circuit for isolated converters with a wide output voltage range

Methods, apparatus, systems, and articles of manufacture are disclosed for adaptive synchronous rectifier control. An example apparatus includes an adaptive off-time control circuit to determine a first voltage and a second voltage when a drain voltage of a switch satisfies a voltage threshold, the first voltage based on a first off-time of the switch, the second voltage based on the first off-time and a first scaling factor, determine a third voltage based on a second scaling factor and a second off-time of the switch, the second off-time after the first off-time, and determine a third off-time of the switch based on at least one of the second voltage or the third voltage. The example apparatus further includes a driver to turn off the switch for at least the third off-time after the second off-time.

Methods and apparatus for adaptive synchronous rectifier control

In some examples, a circuit includes an input circuit, an output circuit, an auxiliary circuit, and a balancing circuit. The input circuit comprises a primary capacitor coupled to primary windings of a transformer. The output circuit comprises a secondary capacitor coupled to secondary windings of the transformer, wherein the secondary windings are coupled to the primary windings. The auxiliary circuit comprises auxiliary windings coupled to the primary windings. The balancing circuit is coupled to the output circuit, the auxiliary circuit, and the input circuit. The balancing circuit is configured to balance a voltage across the primary capacitor with a voltage across the secondary capacitor.

Active clamp capacitor balancing

A synchronous rectifier control circuit includes a drain voltage input, a first gate voltage output, a second gate voltage output, a gate voltage generation circuit, and a trigger control circuit. The gate voltage generation circuit includes a first input coupled to the drain voltage input, and an output coupled to the first gate voltage output. The trigger control circuit includes a first input coupled to the first gate voltage output, a second input coupled to the second gate voltage output, and an output coupled to a second input of the gate voltage generation circuit.

Synchronous rectifier control circuit

In an example, a circuit includes a first power switch device coupled between a voltage input and an output terminal, the first power switch device having a control input. A voltage divider circuit includes a first resistor and a second resistor. The first resistor is coupled between the voltage input and a sense node between the first resistor and the second resistor. The second resistor has a first terminal coupled to the sense node and a second terminal. A second switch device is coupled between the second terminal of the second resistor and an electrical ground terminal. A voltage clamp is coupled between the sense node and the electrical ground terminal.

Multi-mode high voltage circuit

A primary side wireless power transmitter inductively couplable to a secondary side wireless power receiver for supplying power to the wireless power receiver for receiving communications from the secondary side wireless power receiver through the inductive coupling comprises a primary side tank circuit receiving a signal on from the secondary side wireless power receiver. A phase delay or time delay circuit generates a fixed delay clock signal. A sample and hold circuit samples a tank circuit voltage utilizing the fixed phase or time delayed clock signal. A comparator is coupled to an output of the sample and hold circuit for extracting data or commands from the signal stream. A method of operating a primary side wireless transmitter inductively coupled to a secondary side wireless power receiver for supplying power to the wireless power receiver to power a load coupled to the receiver is also disclosed.

Circuit and architecture for a demodulator for a wireless power transfer system and method therefor

A synchronous rectifier control circuit includes a drain voltage input, a gate voltage output, a gate voltage generation circuit, a burst detection circuit, an on-time monitor circuit, and a burst mode reset circuit. The gate voltage generation circuit includes a first input coupled to the drain voltage input, and an output coupled to the gate voltage output. The burst detection circuit includes a first input coupled to the drain voltage input, and an output coupled to a second input of the gate voltage generation circuit. The on-time monitor circuit includes an input coupled to the output of the gate voltage generation circuit. The burst mode reset circuit includes a first input coupled to the drain voltage input, a second input coupled to an output of the on-time monitor circuit, and an output coupled to a second input of the burst detection circuit.

Synchronous rectifier control

A synchronous rectifier controller integrated circuit. The synchronous rectifier controller integrated circuit comprises a continuous current mode (CCM) detection circuit configured to detect CCM operation based on sensing a voltage at a pre-defined point in a rectification cycle; a multiplexer having a first reference voltage signal input, a second reference voltage signal input, an output, and a selector input coupled to the CCM detection circuit; and a gate voltage driver circuit coupled to the output of the multiplexer.

Synchronous rectifier controller integrated circuits

Methods of operating switching power supplies are disclosed. A power supply has a transformer and a switch coupled to the primary side of the transformer for controlling the current flow through the primary side of the transformer. A method includes determining the output voltage of the power supply. A first minimum switching frequency is generated for driving the switch in response to the output voltage being greater than a nominal output voltage and less than a predetermined voltage. A second minimum switching frequency is generated for driving the switch in response to the output voltage being equal to or greater than the predetermined voltage, wherein the first minimum switching frequency is greater than the second minimum switching frequency.

Method and circuitry for controlling a power supply

A system includes control circuitry configured to provide one or more control pulses in response to a command signal, the one or more control pulses being communicated from the control circuitry to associated circuitry via a connection. A detector is configured to detect a disturbing signal that mitigates reception of the one or more control pulses via the connection. The command signal is controlled to cause the control circuitry to provide one or more additional control pulses when the disturbing signal is detected by the detector to improve a likelihood of the reception of the one or more control pulses via the connection.

Growing community of inventors

Merrimack, NH, United States of America

Bharath Balaji Kannan