Texas Instruments Corporation

Texas Instruments Incorporated Deutschland, Gmbh

Martijn Fridus Snoeij

Mikhail Valeryevich Ivanov

Roberto Giampiero Massolini

Viola Schaffer

Steven Graham Brantley

Sudarshan Udayashankar

Brian David Johnson

Viola Schäffer

Srinivas Kumar Pulijala

Bharath Karthik Vasan

Gebhard Haug

Marco Corsi

Sergey V Alenin

Mikhail V Invanov

An amplifier overload power limit circuit, system, and a method thereof comprising a monitoring of a current gain of a BJT based on a current detector and limiting power to the BJT based on the monitored current gain to prevent the BJT from driven into a saturation mode and the amplifier overdrive.

OPAMP overload power limit circuit, system, and a method thereof

A logarithmic amplifier circuit includes an adaptive gain amplifier circuit and a transistor. The adaptive gain amplifier circuit includes a gain stage and a diode. The gain stage includes an input terminal, and an output terminal. The diode includes a cathode terminal coupled to the output terminal, and an anode terminal coupled to a common terminal. The transistor includes a first terminal coupled to the input terminal, a second terminal coupled to the common terminal, and a third terminal coupled to the output terminal.

Logarithmic amplifier circuit

An electrical system includes a power supply and an electrical circuit coupled to the power supply and including an operational amplifier. The operational amplifier includes an input stage and a pre-driver stage coupled to the input stage, wherein the pre-driver stage includes a first input terminal, a second input terminal, and a voltage supply terminal. The operational amplifier also includes an output stage with bipolar transistors coupled to the pre-driver stage. The pre-driver stage is configured to: detect a voltage differential across the first and second input terminals of the pre-driver stage; and provide an adjustable bias current based on the voltage differential.

Pre-driver stage with adjustable biasing

A circuit and method for magnetic field detection is disclosed. A fluxgate sensor comprises a fluxgate having a first core and a second core. A sense coil has a first winding around the first fluxgate core and a second winding around the second fluxgate core. A fluxgate detection circuit is coupled to the sense coil and outputs a signal proportional to an external magnetic field applied to the fluxgate. A detection circuit is coupled to the first winding and outputs a signal that indicates whether voltage pulses have been detected on the first winding.

Fluxgate magnetic field detection method and circuit

In at least some embodiments, a system comprises a frequency generator configured to generate a second clock signal having a second frequency using a first clock signal having a first frequency. The second frequency is offset from the first frequency and each of a plurality of harmonic frequencies of the second frequency is offset from a harmonic frequency of the first frequency. The system also includes a power converter configured to produce a power signal that at least partially corresponds to the second frequency. The system further comprises an analog-to-digital converter (ADC) configured to sample and convert analog voltages at the first frequency. The ADC is powered by the power signal.

Frequency management for interference reduction of A/D converters powered by switching power converters

An integrated fluxgate magnetic gradient sensor includes a common mode sensitive fluxgate magnetometer and a differential mode sensitive fluxgate magnetometer. The common mode sensitive fluxgate magnetometer includes a first core adjacent to a second core. The first and second cores are wrapped by a first excitation wire coil configured to receive an excitation current that affects a differential mode magnetic field. The differential mode sensitive fluxgate magnetometer includes a third core adjacent to the first core and a fourth core adjacent to the second core. The third and fourth cores are wrapped by a second excitation wire coil configured to receive an excitation current that affects a common mode magnetic field.

Integrated fluxgate magnetic gradient sensor

In examples, a system comprises a differential amplifier coupled to a parasitic capacitor positioned between a first node and a first reference voltage source. The system comprises a buffer amplifier having an input terminal and an output terminal, the input terminal coupled to the first node and the output terminal coupled to a cancellation capacitor. The system includes a controlled current source coupled to the first node and the input terminal, the controlled current source coupled to a second reference voltage source. The system comprises a current sense circuit coupled to the cancellation capacitor and the second reference voltage source.

Differential amplifier including cancellation capacitors

An operational amplifier includes an input stage configured to receive a first input voltage and a second input voltage and a slew boost circuit coupled to the input stage and configured to selectively increase current through the input stage. The operational amplifier also includes an output stage coupled to the input stage and configured to generate an output voltage, and a slew boost disable circuit configured to assert a control signal to the slew boost circuit to disable the slew boost circuit. The slew boost circuit is disabled when both: the first input voltage being more than a first threshold voltage different from the second input voltage and the output voltage failing to change by more than a second threshold rate.

Slew boost disable for an operational amplifier

An input stage of an operational amplifier receives first and second input voltages. An output slew detection circuit decreases a first current responsive to slewing of an output of the operational amplifier and increases the first current responsive to no slewing. A slew boost and differential input voltage detection generates a second current at a first level when the first and second input voltages are approximately equal and to generate the second current at a second level, smaller than the first level, responsive to the first and second input voltages not being approximately equal. A voltage on a capacitor increases responsive to the first current from the output slew detection circuit increasing and responsive to the second current being at the second level. A current mirror is activated responsive to the voltage on the capacitor exceeding a second threshold. The current mirror decreases a third current of the input stage.

Improved magnetic sensor excitation circuitry is presented for providing a periodic bidirectional excitation waveform to a fluxgate magnetic sensor excitation coil using a bridge circuit connected to the excitation coil and having lower transistors for switched selective connection to a current mirror input transistor to mirror a current provided by pulsed current source, and with integrated filtering to control pulse rise times and slew rate.

Growing community of inventors

Erding, Germany

Martijn Fridus Snoeij