Texas Instruments Corporation

Apple Inc.

Erhan Ozalevli

Mustapha El Markhi

Tuli Luthuli Dake

Evaldo M Miranda, Jr

Luthuli E Dake

Behzad Mohtashemi

Rohit Bhan

Gianpaolo Lisi

Jingwei Xu

Dingkun Du

Gregory Romas

Mohammad Jafar Navabi-Shirazi

Ching-Yuh Tsay

Yanhui Xie

David G Daniels

Dharmesh C Bhagatwala

Rashed Anam

Gary L Wakeman

Embodiments relate to an amplifier circuit. The amplifier circuit includes multiple transistors. Each transistor is configured to receive an input signal and output an amplified signal. The amplifier circuit additionally includes a set of input chopper circuits and a set of output chopper circuits. Each output chopper circuit corresponds to one input chopper of the set of input choppers. Each input chopper circuit and its corresponding output chopper are controlled by one or more control signals from a set of control signals. Each input chopper circuit is configured to selectively connect each transistor of a transistor pair to a first input terminal or a second input terminal based on a value of the one or more control signals. Moreover, each output chopper circuit is configured to selectively connect each transistor of the transistor pair to a first output terminal or a second output terminal based on the value of the one or more control signals.

Amplifier circuit with distributed dynamic chopping

A power converter circuit is disclosed. In one embodiment, the power converter includes a switching circuit coupled to an input power supply node and a regulated power supply node via an inductor, wherein the switching circuit is configured to source respective charge current to the regulated power supply node during a plurality of active cycles. The power converter further includes a control circuit configured to determine, for a particular active cycle, an average inductor current. The control circuit is further configured to perform a comparison of the average inductor current to a threshold value. Based on results of the comparison, the control circuit is configured to deactivate the switching circuit for a different active cycle subsequent to the particular active cycle. Two methods are disclosed to identify mode transitions, depending on conditions such as minimum time on and discontinuous current mode.

Switching power converter with mode transition control

An example device comprises a digital-to-analog converter (DAC) comprising first and second transistors coupled to a first amplifier, the second transistor coupled to a first output of the DAC and to an output of the first amplifier, and third and fourth transistors coupled to the first amplifier and to a second output of the DAC, the third and fourth transistors switchably coupled to a voltage supply and to the first transistor. The device also comprises a first node coupled to the first output of the DAC and to a resistor. The device further includes a second node coupled to the second output of the DAC, and a second amplifier coupled to the second node and to the first transistor and switchably coupled to the third and fourth transistors. The device also comprises a comparator coupled to the first node.

Battery charging and measurement circuit

Embodiments relate to a power monitoring circuit. The power monitoring circuit includes a divider circuit that generates a reference voltage that is inversely proportional to a regulator voltage. Moreover, the power monitoring circuit includes an integrator that generates an integrator voltage by integrating one or more regulator currents. The power monitoring circuit additionally includes a comparator for comparing the output of the divider circuit and the output of the integrator. The comparator of the power monitoring circuit generates an output signal in response to the integrator voltage being larger than the reference voltage.

Power measurement and monitoring circuit for switching regulators

An amplifier circuit includes multiple transistors, a set of input routing circuits, and a set of output routing circuits. Each output routing circuit corresponds to an input routing circuit. Each input routing circuit and its corresponding output routing circuit are controlled by one or more control signals. Each input routing circuit is configured to selectively connect each transistor of a transistor pair to a first input terminal of the amplifier circuit, a second input terminal of the amplifier circuit, or a third input terminal of the amplifier based on a value of the one or more control signals. Each output routing circuit is configured to selectively connect each transistor of the transistor pair to a first output terminal of the amplifier circuit, a second output terminal of the amplifier circuit, or a calibration circuit based on the value of the one or more control signals.

Amplifier circuit with dynamic offset calibration

Embodiments relate to a switching regulator having a dual mode control. The switching regulator includes an error amplifier configured to receive an output voltage of a power source, and to generate an error voltage based on a difference between the output voltage of the power source and a reference voltage. The switching regulator additionally includes a PFM controller configured to receive the error voltage from the error amplifier, and to generate a clock signal having a switching frequency based on a difference between the error voltage and a modulation voltage. Moreover, the switching regulator includes a PWM controller configured to receive the clock signal and an error signal determined based on a load current sensed at an output of the power source, and to generate a control signal to control the power source.

Pulse frequency modulation and frequency avoidance method and implementation for switching regulators

A wireless power transfer system using a resonant rectifier circuit with capacitor sensing. A wireless power transfer system includes a power receiver resonant circuit and a synchronous rectifier. The power receiver resonant circuit includes an inductor and a capacitor connected in series with the inductor. The synchronous rectifier is configured to identify zero crossings of alternating current flowing through the inductor based on voltage across the capacitor, and control synchronous rectification of the alternating current based on timing of the zero crossings.

Resonant rectifier circuit with capacitor sensing

Embodiments relate to sensing a current provided by a power supply circuit. The current sensing circuit includes a sense transistor for sensing the current provided by a main transistor, a driver for controlling a bias provided to the sense transistor and the main transistor, and a sense resistor for converting the sensed current to a voltage value. Moreover, the current sensing circuit includes a controller that modifies at least one of: (a) a resistance of the main transistor by adjusting the bias voltage provided by the driver, (b) a gain ratio between a load current and a sensing current by adjusting a number of individual devices that are active in the sense transistor, and (c) a resistance of the sense resistor.

Dynamically controlled auto-ranging current sense circuit

One example includes a phase-locked loop (PLL) circuit. The circuit includes a frequency divider and phase detector configured to generate a plurality of non-overlapping switching signals based on an input signal and a PLL output signal. The circuit also includes a linear frequency-to-current (F2I) converter configured to generate a control current having an amplitude that is based on the plurality of non-overlapping switching signals. The circuit further includes a linear current-controlled oscillator configured to generate the PLL output signal to have a frequency and phase to be approximately equal to the input signal based on the amplitude of the control current.

Phase-locked loop (PLL) circuit

LED backlight circuits for a display and methods for operating the circuits are disclosed. The LED backlight circuit includes a set of drivers and a set of LED strings. A driver can control a light output level of the LED strings. The LED strings can be controlled by a mixed-mode LED driver that utilizes a PWM control signal over a first range of light output levels and an analog control signal over a second range of light output levels. Clock signals used for PWM control and for frequency-to-current or frequency-to-voltage conversion for analog control can both be generated from a phase locked loop (PLL).

Frequency-to-current/voltage converter based mixed-mode LED drivers

In a described example, an apparatus includes: transistor having a first terminal coupled to an input terminal, a second terminal coupled to an output terminal, and a gate terminal; a temperature sensor configured to sense a junction temperature of the transistor and generate a temperature signal based on the sensed junction temperature; and a gate driver circuit configured to generate a gate signal based on the temperature signal and to output the gate signal to the gate terminal of the transistor.

DC-DC power conversion circuitry with efficiency optimization using temperature sensing

LED backlight circuits for a display and methods for operating the circuits are disclosed. The LED backlight circuit includes a set of drivers and a set of LED strings. A driver can be capable of coupling to any of the LED strings at a given time. Examples of the disclosure can include different configurations of drivers. In some instances, the driver may include an auxiliary transistor that allows the driver to settle before being switched to control a respective LED string. In some examples, the driver can include switches and an idle transistor that can be operated such that a low current path through the driver can exist when the driver is not coupled to a LED string.

Multi-string LED drivers and current switching techniques

Aspects of the present disclosure provide for a circuit, comprising a first node configured to couple to a first current source and a second current source. The circuit also comprises a first filter configured to couple between a voltage supply and the first node, the first filter being a first dynamically controllable current filter. The circuit further comprises a current mirror coupled between the first node and a second node configured to couple to a third current source and a fourth current source. The circuit additionally comprises a second filter configured to couple between the second node and a ground node, the second filter being a second dynamically controllable current filter.

Growing community of inventors

Santa Clara, CA, United States of America

Erhan Ozalevli