Texas Instruments Corporation

Ganapathi Shankar

Venkata Naresh Kotikelapudi

Vishal I Gupta

Venkatesh Guduri

Richeek Maitra

Varun Garg

Sreenath Puthumana

A circuit includes an amplifier having a first input, a reference input, and an output. A pulse width modulator (PWM) controller has an input coupled to the output of the amplifier. A first switch has a control terminal coupled to an output of the PWM controller. A second switch has a second terminal coupled to the second terminal of the first switch, and has a control terminal coupled to the output of the PWM controller. An input of a current sensor is coupled to the second terminal of the first switch and is coupled to a second terminal of the second switch. An output of the current sensor is coupled to the first input of the amplifier. A duty cycle monitoring and reference signal adjustment circuit has an input coupled to the output of the PWM controller and has an output coupled to the reference input of the amplifier.

Adaptive slope compensation in solenoid drivers to avoid instability in current regulation

A load current sensing circuit includes a sense leg including a sense transistor with a gate coupled to the output of a high-side gate driver, a feedback transistor, and a sense resistor coupled in series between a power supply and ground. An amplifier has differential inputs coupled to the sense leg and to an output, and an output coupled to the feedback transistor gate. A bias circuit has a first transistor coupled between the power supply voltage and the first bias voltage terminal, and a gate receiving, from a first leg, a first differential from the output voltage. A second leg in the amplifier bias circuit generates a gate voltage, for a second transistor coupled between ground and a second bias voltage terminal, that is at a second differential from a voltage at the first bias voltage terminal. The amplifier is biased between the first and second bias voltages.

Bias generation for bridge driver load current sensing

An example apparatus includes: memory including machine-readable instructions; programmable circuitry configured to execute the machine-readable instructions of the memory configured to: determine a first value of power transferred to a stepper motor during a first operation of the stepper motor; determine a second value of power transferred to the stepper motor during a second operation of the stepper motor; determine a load angle of power delivered by the stepper motor during the first operation and second operation of the stepper motor based on the first value, the second value, and a stall power; and compare the load angle to a stall threshold to detect a stall of the stepper motor.

Methods and apparatus to detect a stall of a stepper motor

An example circuit includes a transistor including a first current terminal, a second current terminal, and a control terminal, the first current terminal of the transistor coupled to a load terminal, the second current terminal of the transistor coupled to a ground; a sense transistor including a first current terminal, a second current terminal, and a control terminal, the second current terminal of the sense transistor coupled to the ground; an amplifier including a first input, a second input, and an output terminal, the second input of the amplifier coupled to the output terminal of the amplifier; and a resistor including a first terminal and a second terminal, the first terminal of the resistor coupled to the output terminal of the amplifier and the control terminal of the transistor, and the second terminal coupled to the control terminal of the sense transistor.

Methods and apparatus to improve accuracy of current sense circuitry

A fast blocking switch includes, for example, an energy storage device, a first power switch and a second power switch. The energy storage device stores a charge for fast activation of the switches. The first switch is operable for coupling input current to an output terminal in response to the coupling of a potential supplied by the stored charge to a control terminal of the first switch. The second switch is operable for coupling a limited amount of the input current to the output terminal in response to the coupling of a potential supplied by the stored charge to a control terminal of the second switch.

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Bengaluru, India

Ganapathi Shankar