A pre-driving stage drives one or more Field Effect Transistors in a power stage driving a load. A method for measuring current flowing in the Field Effect Transistors includes: measuring drain to source voltages of the one or more Field Effect Transistor; and measuring an operating temperature of the one or more Field Effect Transistor. The current flowing in the Field Effect Transistors is measured by: calculating the respective on drain to source resistance at the operating temperature as a function of the measured operating temperature and obtaining the current value as a ratio of the respective measured drain to source voltage over the calculated drain to source resistance at the operating temperature.

A circuit system for measuring an electrical voltage. The circuit system includes a voltage divider, an integrating element and an evaluating unit. The voltage divider receives, at an input, a first signal that represents the electrical voltage to be measured, and has a first switching element and a second switching element, and is capable of assuming a first state, in which the first switching element is conductive and the second switching element is non-conductive, and a second state in which the first switching element is non-conductive and the second switching element is conductive, and outputs a second signal at an output that is situated between the first switching element and the second switching element. The integrating element is designed to receive the second signal and to output a third signal. The evaluating unit being set up to accept and to evaluate the third signal in order to determine a value for the electrical voltage.

A circuit system for measuring an electrical voltage. The circuit system includes a voltage divider, an integrating element and an evaluating unit. The voltage divider receives, at an input, a first signal that represents the electrical voltage to be measured, and has a first switching element and a second switching element, and is capable of assuming a first state, in which the first switching element is conductive and the second switching element is non-conductive, and a second state in which the first switching element is non-conductive and the second switching element is conductive, and outputs a second signal at an output that is situated between the first switching element and the second switching element. The integrating element is designed to receive the second signal and to output a third signal. The evaluating unit being set up to accept and to evaluate the third signal in order to determine a value for the electrical voltage.

An AD converter with self-calibration function that does not require an instrument for calibration, and includes: a reference voltage unit that generates a reference voltage; a summation and conversion unit that has two or more unit voltages serving as units of amount of change in a summed voltage, and during conversion, sums up any one unit voltage of the two or more unit voltages until the summed voltage exceeds the reference voltage, with an input voltage being an initial value of the summed voltage; and a control unit including a calibration control section that calibrates the two or more unit voltages and an offset voltage of a comparator at a time of calibration, and a conversion control section that determines a polarity of the offset voltage of the comparator and thereafter converts the input voltage to a digital value during conversion.

An electronic device having an overcurrent protection function is provided. The electronic device includes at least one power converter, the at least one power converter including a power conversion unit to convert input voltage or input current to supply output current, a control unit to adjust the output current, and an overcurrent protection unit to detect the output current and transmit a detection result to the control unit, and wherein the overcurrent protection unit includes an overcurrent extraction module to output a difference between the output current exceeding designated first reference current and the first reference current; a calculation module to calculate an accumulative value obtained by integrating the difference with respect to time, and a first comparison module to compare the accumulative value with a designated critical value and to transmit a first detection result in which the accumulative value exceeds the critical value to the control unit.

Methods and systems for emulating high side current of a power switch including low and high side switches. The method includes generating, with a low side current sensor, a low side current signal for the low side switch when the power switch is in a low state. The method also includes generating, with a first transconductance amplifier, an emulated current signal based on an input voltage of the power switch. The method further includes generating, with a buffer, a fixed reference voltage by sampling the low side current signal when the power switch changes from the low state to a high state. The method also includes generating, with a capacitor, an emulated voltage based on the emulated current signal and the fixed reference voltage. The method further includes, generating, with a second transconductance amplifier, a high side current signal for the high side switch based on the emulated voltage.

Methods and systems for emulating high side current of a power switch including low and high side switches. The method includes generating, with a low side current sensor, a low side current signal for the low side switch when the power switch is in a low state. The method also includes generating, with a first transconductance amplifier, an emulated current signal based on an input voltage of the power switch. The method further includes generating, with a buffer, a fixed reference voltage by sampling the low side current signal when the power switch changes from the low state to a high state. The method also includes generating, with a capacitor, an emulated voltage based on the emulated current signal and the fixed reference voltage. The method further includes, generating, with a second transconductance amplifier, a high side current signal for the high side switch based on the emulated voltage.

An impedance sensing circuit includes first and second current sources and first and second bias current sources that are appropriately coupled to first and second resistors. The impedance sensing circuit also includes a comparator that compares a first voltage based on the first terminal of the first resistor to a second voltage based on the first terminal of the second resistor to generate a comparator output signal. Either the comparator output signal or a digital signal based on the comparator output signal operates to regulate the current signals output from the first and second current sources so that the first voltage is same as the second voltage. The comparator output signal and the digital signal is representative of a difference between the first voltage and the second voltage that is based on an impedance difference between the first resistor and the second resistor.

An impedance sensing circuit includes first and second current sources and first and second bias current sources that are appropriately coupled to first and second resistors. The impedance sensing circuit also includes a comparator that compares a first voltage based on the first terminal of the first resistor to a second voltage based on the first terminal of the second resistor to generate a comparator output signal. Either the comparator output signal or a digital signal based on the comparator output signal operates to regulate the current signals output from the first and second current sources so that the first voltage is same as the second voltage. The comparator output signal and the digital signal is representative of a difference between the first voltage and the second voltage that is based on an impedance difference between the first resistor and the second resistor.

Device for ratiometric measurement of voltages for an analog-digital converter, wherein the device comprises a functional providing unit, a microcontroller and a first sensor, wherein a reference voltage is provided to the microcontroller and a first supply voltage is provided to the first sensor and the microcontroller by the functional providing unit, and wherein the first sensor is connected to the microcontroller in terms of signalling by transmitting sensor signals, and wherein the microcontroller comprises a first multiplexer and a second multiplexer, wherein the multiplexers outputs signals to the analog-digital-converter. According to the invention, it is provided that the reference voltage and the first supply voltage are in each case present on the input side at the first multiplexer and at the second multiplexer, wherein in a first switching state the first supply voltage can be measured on the output side by using the reference voltage as a reference for the analog-digital-converter and in a second switching state the reference voltage can be measured by using the first supply voltage as a reference for the analog-digital-converter.