Abstract: A test method and system are provided for testing a switched mode power supply in open loop on an automated test equipment device by applying a low frequency waveform signal (209) to a compensator filter (225) and simultaneously capturing and processing the input (223) and output (222) to the compensator filter (225) to determine the phase difference therebetween.

Abstract: A programmable temperature sensing circuit includes a comparator, first and second CTAT sensing elements, first and second PTAT reference circuits, and a selection circuit. When a selection signal is a first logic state, an output terminal of the first PTAT reference circuit is coupled to the second CTAT temperature sensing element for providing a first threshold voltage to the second input of the comparator. When the selection signal is a second logic state different from the first logic state, a series-connection of the first PTAT reference circuit and the second PTAT reference circuit are coupled to the second CTAT temperature sensing element for providing a second threshold voltage to the second input of the comparator. The comparator provides an output voltage indication when a voltage provided by the first CTAT sensing element compares favorably with the selected one of the first or second threshold voltages.

Abstract: A data processing system includes a brown-out detection circuit with a first resistive element, a first transistor, a second transistor, and a comparator. The first resistive element has a first terminal coupled to a first power supply voltage terminal, and a second terminal. The first transistor has a first current electrode coupled to the second terminal of the first resistive element, a control electrode, and a second current electrode. The second transistor has a first current electrode coupled to the second current electrode of the first transistor, a control electrode, and a second current electrode coupled to a second power supply voltage terminal. The comparator has a first input terminal coupled to the first terminal of the first resistive element, a second input terminal coupled to the second terminal of the first resistive element, and an output terminal for providing a brown-out detection signal.

Abstract: A data processing system includes a brown-out detection circuit with a first resistive element, a first transistor, a second transistor, and a comparator. The first resistive element has a first terminal coupled to a first power supply voltage terminal, and a second terminal. The first transistor has a first current electrode coupled to the second terminal of the first resistive element, a control electrode, and a second current electrode. The second transistor has a first current electrode coupled to the second current electrode of the first transistor, a control electrode, and a second current electrode coupled to a second power supply voltage terminal. The comparator has a first input terminal coupled to the first terminal of the first resistive element, a second input terminal coupled to the second terminal of the first resistive element, and an output terminal for providing a brown-out detection signal.

Abstract: A programmable temperature sensing circuit includes a comparator, first and second CTAT sensing elements, first and second PTAT reference circuits, and a selection circuit. When a selection signal is a first logic state, an output terminal of the first PTAT reference circuit is coupled to the second CTAT temperature sensing element for providing a first threshold voltage to the second input of the comparator. When the selection signal is a second logic state different from the first logic state, a series-connection of the first PTAT reference circuit and the second PTAT reference circuit are coupled to the second CTAT temperature sensing element for providing a second threshold voltage to the second input of the comparator. The comparator provides an output voltage indication when a voltage provided by the first CTAT sensing element compares favorably with the selected one of the first or second threshold voltages.

Abstract: A data processing system (100), such as a System-on-Chip, includes a processor (120), a memory (140) that has an expected minimum data retention voltage, and a brown-out detector (160), which includes a brown-out detection circuit (201) that has an analog output, and an output circuit (248 and 252) that converts the analog output of the brown-out detection circuit to a digital brown-out flag. The brown-out detection circuit includes a self-biased current reference, current mirrors, and a current comparator. The brown-out detector monitors voltage of a power supply of the memory, and the brown-out detector asserts the digital brown-out flag to the processor when the voltage of the power supply is at, or slightly above, a highest expected minimum data retention voltage.

Abstract: A brown-out detection circuit includes a first resistive element, a first transistor, a second transistor, and a comparator. The first resistive element has a first terminal coupled to a first power supply voltage terminal, and a second terminal. The first transistor is of a first conductivity type and has a first current electrode coupled to the second terminal of the first resistive element, a control electrode, and a second current electrode. The second transistor is of a second conductivity type and has a first current electrode coupled to the second current electrode of the first transistor, a control electrode, and a second current electrode coupled to a second power supply voltage terminal. The comparator has a first input terminal coupled to the first terminal of the first resistive element, a second input terminal coupled to the second terminal of the first resistive element, and an output terminal for providing a brown-out detection signal.

Abstract: A data processing system (100), such as a System-on-Chip, includes a processor (120), a memory (140) that has an expected minimum data retention voltage, and a brown-out detector (160), which includes a brown-out detection circuit (201) that has an analog output, and an output circuit (248 and 252) that converts the analog output of the brown-out detection circuit to a digital brown-out flag. The brown-out detection circuit includes a self-biased current reference, current mirrors, and a current comparator. The brown-out detector monitors voltage of a power supply of the memory, and the brown-out detector asserts the digital brown-out flag to the processor when the voltage of the power supply is at, or slightly above, a highest expected minimum data retention voltage.

Abstract: A method includes receiving a set of voltages comprising at least a first voltage, a second voltage, and a third voltage and biasing a well of a transistor based on the extreme voltage of the set of voltages. Biasing the well of the transistor can include concurrently providing a first signal and a second signal based on a comparison of the first voltage and the second voltage and selectively coupling the well of the transistor to a source of the extreme voltage of the set of voltages based on the first signal, the second signal, and the third voltage. An electronic device comprises a transistor and a power switching module. The power switching module includes a set of inputs, each input configured to receive a corresponding one of a set of voltages comprising at least a first voltage, a second voltage, and a third voltage, and includes an output coupled to a well of the transistor, the output configured to provide the extreme voltage of the set of voltages.

Abstract: A voltage regulator includes a transistor, a comparator, and a compensation circuit. The comparator has a first input terminal coupled to receive a clock signal, a second input terminal, and an output terminal coupled to a control electrode of the transistor. The compensation circuit has a first input terminal coupled to receive a reference voltage, a second input terminal coupled to the output terminal of the voltage regulator, and an output terminal coupled to the second input terminal of the comparator. The compensation circuit has a filter circuit. The filter circuit has a first RC time constant during startup of the voltage regulator, and the filter circuit has a second RC time constant during normal operation. Changing the RC time constant for startup prevents an overshoot of an output voltage of the voltage regulator.

Abstract: A programmable voltage reference includes a temperature compensated current source and a voltage reference circuit. The temperature compensated current source includes an output configured to provide a reference current. The voltage reference circuit includes an input coupled to the output of the temperature compensated current source and a reference output. The voltage reference circuit includes a self-cascode metal-oxide semiconductor field-effect transistor structure that includes a first device that is diode-connected and operates in a weak inversion saturation region and a second device that operates in a weak inversion triode region. A length of the second device is selectable. The voltage reference circuit is configured to provide a reference voltage on the reference output based on the reference current.

Abstract: A brown-out detection circuit comprises a first resistive element, a first transistor, a second transistor, and a comparator. The first resistive element has a first terminal coupled to a first power supply voltage terminal, and a second terminal. The first transistor is of a first conductivity type and has a first current electrode coupled to the second terminal of the first resistive element, a control electrode, and a second current electrode. The second transistor is of a second conductivity type and has a first current electrode coupled to the second current electrode of the first transistor, a control electrode, and a second current electrode coupled to a second power supply voltage terminal. The comparator has a first input terminal coupled to the first terminal of the first resistive element, a second input terminal coupled to the second terminal of the first resistive element, and an output terminal for providing a brown-out detection signal.

Abstract: An oscillator circuit has a crystal oscillator amplifier having only two clock input terminals, one being an input terminal and the other being an output terminal. The input terminal allows a user of the integrated circuit to choose between connecting a first clock signal generated from a crystal or a second clock signal generated by a non-crystal source to the input terminal. Control circuitry has a capacitor coupled in parallel with a transistor. Both are coupled in series with a resistive device at an output of the control circuitry to provide a control signal. Clock generation circuitry coupled to the crystal oscillator amplifier provides an oscillating output signal in response to an enable signal. In one form a comparator circuit provides the oscillating output signal. The control signal is used to ensure that inputs to the comparator circuit repeatedly cross each other over time.

Abstract: An oscillator circuit has a crystal oscillator amplifier having only two clock input terminals, one being an input terminal and the other being an output terminal. The input terminal allows a user of the integrated circuit to choose between connecting a first clock signal generated from a crystal or a second clock signal generated by a non-crystal source to the input terminal. Control circuitry has a capacitor coupled in parallel with a transistor. Both are coupled in series with a resistive device at an output of the control circuitry to provide a control signal. Clock generation circuitry coupled to the crystal oscillator amplifier provides an oscillating output signal in response to an enable signal. In one form a comparator circuit provides the oscillating output signal. The control signal is used to ensure that inputs to the comparator circuit repeatedly cross each other over time.

Abstract: A touch panel detection circuit includes current limiting circuitry that has a first portion coupled between a first supply voltage terminal and a first input node and a second portion coupled between a second input node and a second supply voltage terminal. Programmable precharge circuitry connects the first input node to the first supply voltage terminal via a conductive path that is in parallel with the first portion of the current limiting circuitry and precharges the first input node to a predetermined voltage. Comparison circuitry is coupled to the programmable precharge circuitry and to the first input node. The comparison circuitry detects a change in resistance between the first input node and the second input node and provides a signal in response thereto when the comparison circuitry is enabled by the programmable precharge circuitry.

Abstract: A method and system for decoding a received data stream are disclosed. The appropriate time interval to decode the received data stream is derived from the data stream itself. A header of the data stream is analyzed to determine two sets of time ranges, each set of time ranges corresponding to a set of possible data transmission intervals. A preamble of the header contains timing information for development of a first set of time ranges to decode a synchronization word of the header. The synchronization word contains both data information and timing information to develop the second set of time ranges. The data information included in the header is used validate the data stream for the receiving device. The second set of time ranges is used to decode a data payload portion of the data stream.

Abstract: An amplifier has an input stage coupled to a current mirror for providing a first control signal. A gain boosting stage has first and second sections, each having first and second inputs and an output. The first input of the first section is coupled to the input stage. The second input of the first section is a first node between a source and a drain of a first pair of series-coupled transistors. The first input of the second section is coupled to the current mirror. The second input of the second section is a second node between a source and a drain of a second pair of series-coupled transistors. A pre-driver stage has inputs coupled to the input stage and the gain boosting stage. The pre-driver stage provides inputs to the gain boosting stage and receives outputs from the gain boosting stage prior to coupling to an output stage.

Abstract: A programmable voltage reference includes a temperature compensated current source and a voltage reference circuit. The temperature compensated current source includes an output configured to provide a reference current. The voltage reference circuit includes an input coupled to the output of the temperature compensated current source and a reference output. The voltage reference circuit includes a self-cascode metal-oxide semiconductor field-effect transistor structure that includes a first device that is diode-connected and operates in a weak inversion saturation region and a second device that operates in a weak inversion triode region. A length of the second device is selectable. The voltage reference circuit is configured to provide a reference voltage on the reference output based on the reference current.

Abstract: A detector circuit for detecting the presence of a remote capacitive sensor having at least two terminals connected via a protection circuit that includes one or more capacitors, the detector circuit comprising: a current supply for changing the charge on the sensor and the protection circuit, a detector for measuring the voltage on one or more of the terminals; wherein the presence of the sensor is determined by changing the charge on the capacitive sensor and the one or more capacitors of the protection circuit in a predetermined manner such that the voltage measurement on the one or more terminals when the sensor is present is significantly different than when the sensor is absent.

Abstract: A method includes driving a current through a touch screen that is based on contact of the touch screen, generating a proportional second current, and detecting contact of the touch screen from the second current. Another method includes providing a touch screen with parallel plates, disabling contact detection when a plate voltage is lower than a threshold voltage, and enabling contact detection when the plate voltage is at least equal to the threshold voltage. A device includes a first node and a second node coupled to a touch screen, a third node, a first current mirror coupled to the second node and the third node configured to generate a current at the third node that is proportional to a second current at the second node, and a detection circuit that provides a signal based on the first current that indicates contact of the touch screen.