Abstract: A voltage monitor circuit that signals if an input voltage is above or below an internally established reference level proportional to the bandgap voltage of silicon. The voltage monitor circuit mitigates main error sources generally associated with bandgap reference generation such that high accuracy and good performance may be achieved at low power cost. The techniques allow voltage monitors (e.g., brown-out and power on reset (POR) detectors) to be implemented with higher accuracy, lower power consumption, smaller area cost, and support to lower supply voltage than other solutions.

Abstract: A voltage monitor circuit that signals if an input voltage is above or below an internally established reference level proportional to the bandgap voltage of silicon. The voltage monitor circuit mitigates main error sources generally associated with bandgap reference generation such that high accuracy and good performance may be achieved at low power cost. The techniques allow voltage monitors (e.g., brown-out and power on reset (POR) detectors) to be implemented with higher accuracy, lower power consumption, smaller area cost, and support to lower supply voltage than other solutions.

Abstract: A low power temperature detection method, system, and apparatus sense when a temperature threshold is reached by connecting a current conveyor (111) with a startup bias circuit (112) having a first FET (P1) (connected to level shift a reference voltage to provide an input voltage VS1), a first diode-connected BJT (Q0) (connected to generate a base-emitter voltage based on the junction temperature), and a second FET (P2) (connected to level shift the base-emitter voltage), where the startup bias circuit (112) selectively connects the current conveyor (111) to ground to form a closed loop that is activated only when an emitter current at the first diode-connected BJT (Q0) enters a self-turned-on operation region, thereby activating the current conveyor to detect a temperature threshold being reached by the device junction temperature.

Abstract: A temperature detection circuit includes a first current path and a second current path. The first current path includes a first transistor with a control terminal coupled to receive a reference voltage and includes a temperature sensing device. The second current path includes a second transistor with a control terminal coupled to a node of the first current path. The second current path includes a node that provides an indication of a detected temperature.

Abstract: An integrated circuit includes an analog-to-digital converter (ADC) configured to receive input voltage, and first and second reference voltages, and outputs digital code representing ratios between the input voltage and the first and the second reference voltages. The first and second reference voltages are generated by a reference generator using different current densities. During a first stage, the ADC samples the first input voltage and the first reference voltage and transfers equivalent charge of the sampled first input voltage and first reference voltage to an integration capacitor. During a second stage, the ADC samples the second reference voltage and transfers equivalent charge of the sampled second reference voltage to the integration capacitor. The ADC provides one bit of digital code based on total charge stored on the integration capacitor after the transfers of charge of the sampled input voltage, and the sampled first and second reference voltages.

Abstract: A low power relaxation oscillator circuit includes, in one embodiment, a first comparator for comparing voltages at first and second inputs, respectively, a first capacitor coupled to the first input of the first comparator, and a first circuit configured for charging the first capacitor to a first voltage. The first voltage is related to a propagation delay of the first comparator.

Abstract: An integrated circuit includes an analog-to-digital converter (ADC) configured to receive input voltage, and first and second reference voltages, and outputs digital code representing ratios between the input voltage and the first and the second reference voltages. The first and second reference voltages are generated by a reference generator using different current densities. During a first stage, the ADC samples the first input voltage and the first reference voltage and transfers equivalent charge of the sampled first input voltage and first reference voltage to an integration capacitor. During a second stage, the ADC samples the second reference voltage and transfers equivalent charge of the sampled second reference voltage to the integration capacitor. The ADC provides one bit of digital code based on total charge stored on the integration capacitor after the transfers of charge of the sampled input voltage, and the sampled first and second reference voltages.

Abstract: A low power temperature detection method, system, and apparatus sense when a temperature threshold is reached by connecting a current conveyor (111) with a startup bias circuit (112) having a first FET (P1) (connected to level shift a reference voltage to provide an input voltage VS1), a first diode-connected BJT (Q0) (connected to generate a base-emitter voltage based on the junction temperature), and a second FET (P2) (connected to level shift the base-emitter voltage), where the startup bias circuit (112) selectively connects the current conveyor (111) to ground to form a closed loop that is activated only when an emitter current at the first diode-connected BJT (Q0) enters a self-turned-on operation region, thereby activating the current conveyor to detect a temperature threshold being reached by the device junction temperature.

Abstract: A low power relaxation oscillator circuit includes, in one embodiment, a first comparator for comparing voltages at first and second inputs, respectively, a first capacitor coupled to the first input of the first comparator, and a first circuit configured for charging the first capacitor to a first voltage. The first voltage is related to a propagation delay of the first comparator.

Abstract: A sample and hold circuit configured to sample a current includes an input node to receive the current, a capacitor coupled with a sampling node and a reference voltage node, switch between the input node and the sampling node, a controlled current source coupled to the input node, a current mirror circuit having connections each providing a mirrored current, wherein at least one of said connections provides an output node, and a transistor arrangement. The transistor arrangement includes a control MOSFET in series with a series connected chain of cascaded cells. The control MOSFET and each of said cascaded cells are coupled to the current mirror circuit and each of the cascaded cells includes a pair of MOSFETs arranged to provide a voltage difference including a difference between a gate-source voltage of a first of the pair and a gate-source voltage of a second of the pair.

Abstract: A sample and hold circuit configured to sample a current includes an input node to receive the current, a capacitor coupled with a sampling node and a reference voltage node, switch between the input node and the sampling node, a controlled current source coupled to the input node, a current mirror circuit having connections each providing a mirrored current, wherein at least one of said connections provides an output node, and a transistor arrangement. The transistor arrangement includes a control MOSFET in series with a series connected chain of cascaded cells. The control MOSFET and each of said cascaded cells are coupled to the current mirror circuit and each of the cascaded cells includes a pair of MOSFETs arranged to provide a voltage difference including a difference between a gate-source voltage of a first of the pair and a gate-source voltage of a second of the pair.

Abstract: A low power comparator circuit is provided. The circuit includes a comparator core including a first stage. The first stage has an output configured to provide a digital value. A capacitor includes a first terminal coupled at an input of the first stage and a second terminal selectively coupled to a first input and a second input of the comparator core. A voltage generator is coupled to the first stage. The voltage generator is configured and arranged to generate a first voltage based on a predetermined input current and to limit a maximum current of the first stage based on the predetermined input current.

Abstract: A first switch is operable to couple a start-up oscillator circuit to a first crystal pin during operation in a start-up mode and decouple the start-up oscillator circuit from the first crystal pin during operation in a normal mode, and a second switch is operable to couple the start-up oscillator circuit to a second crystal pin during operation in the start-up mode and decouple the start-up oscillator circuit from the second crystal pin during operation in the normal mode. A switched oscillator circuit is coupled to the startup oscillator during operation in the startup mode, and to the first and second crystal pins during operation in the start-up and normal modes. The switched oscillator circuit includes a sample and charge circuit which is configured to sample a direct current (DC) level of the first crystal pin and pre-charge a first coupling capacitor during operation in the startup mode.

Abstract: A bandgap voltage regulator includes a proportional-to-absolute-temperature (PTAT) circuit, an amplifier, and a driver circuit. The PTAT circuit can include various transistors that output a corresponding control voltage. The amplifier generates another control voltage to compensate base-current variations associated with the transistors of the PTAT circuit. The control voltage is generated by the amplifier based on the control voltage outputted by the PTAT circuit, and one of a base-emitter voltage associated with a transistor of the PTAT circuit, a scaled down version of the control voltage outputted by the amplifier, and a scaled down version of the base-emitter voltage. The driver circuit outputs, based on a supply voltage and the control voltages outputted by the PTAT circuit, a reference voltage for driving a functional circuit.

Abstract: An integrated circuit device includes a level shifter circuit with a supply voltage rail to provide a supply voltage, a first pull-up circuit coupled between the supply voltage rail and a first node, a second pull-up circuit coupled between the supply voltage rail and a second node, a first switch including a first terminal coupled to the supply voltage rail, a second terminal coupled to the first node, and a control terminal coupled to the second node, and an inverter including an input terminal coupled to the first node, a voltage supply terminal coupled to the supply voltage, and an output terminal to provide an output voltage from the level shifter circuit.

Abstract: A temperature detection circuit includes a first current path and a second current path. The first current path includes a first transistor with a control terminal coupled to receive a reference voltage and includes a temperature sensing device. The second current path includes a second transistor with a control terminal coupled to a node of the first current path. The second current path includes a node that provides an indication of a detected temperature.

Abstract: A low power comparator circuit is provided. The circuit includes a comparator core including a first stage. The first stage has an output configured to provide a digital value. A capacitor includes a first terminal coupled at an input of the first stage and a second terminal selectively coupled to a first input and a second input of the comparator core. A voltage generator is coupled to the first stage. The voltage generator is configured and arranged to generate a first voltage based on a predetermined input current and to limit a maximum current of the first stage based on the predetermined input current.

Abstract: A clock generation circuit includes a switched capacitor circuit for providing a discrete amount of charge to a resonator for sustaining energization of the resonator at specific portions of the clock cycle.

Abstract: An embodiment for an integrated circuit for temperature detection includes: a closed loop circuit branch including: a first bipolar junction transistor (BJT), a first resistor coupled between a first base of the first BJT and a junction node, and an amplifier having an output coupled to the junction node and a non-inverting input coupled to a collector of the first BJT; and an open loop circuit branch including: a second BJT, a second resistor coupled between a base of the second BJT and the junction node, a third resistor coupled between the base of the second BJT and ground, and a comparator having an inverting input coupled to a collector of the second BJT and an output configured to provide a digital voltage signal that corresponds to a temperature reading.

Abstract: An integrated circuit (IC) is disclosed that includes a load circuit, and a voltage regulator circuit configured to provide a load voltage and a load current to the load circuit. The voltage regulator circuit can regulate the load voltage based on the load current.