A band-gap reference circuit including a charge pump circuit and a reference circuit is disclosed. The charge pump circuit is powered by a supply voltage and thereby outputs a regulating voltage which is higher than the supply voltage and powers the reference circuit such that the reference circuit outputs a band-gap reference voltage. Powering the reference circuit with the regulating voltage that is made higher than the supply voltage by the charge pump circuit enables 1) normal operation of the band-gap reference circuit at the supply voltage that is lower than a lowest voltage required by the band-gap reference circuit; and 2) minimization (almost elimination) of fluctuations in the regulating voltage output from the charge pump circuit and hence a stable and more accurate band-gap reference voltage output from the band-gap reference circuit.

A switch-mode power supply includes a DC-DC converter and metering circuitry that is coupled to the DC-DC converter. The metering circuitry includes scaling circuitry, a current source, a capacitor, switching circuitry, and a comparator. The scaling circuitry is configured to generate a reference current scaled to be a predetermined fraction of a peak current flowing in an inductor of the DC-DC converter. The current source is configured to output a first current that is one-half of the reference current. The capacitor is coupled to the current source. The switching circuitry is configured to switchably connect the current source to the capacitor. The comparator is coupled to the capacitor. The comparator is configured to generate a signal indicating that a voltage across the capacitor exceeds a threshold voltage.

A bandgap reference circuit and method of using the same are provided. The bandgap reference circuit includes a startup component; an output component; and a bandgap core component coupled there-between. The bandgap core component includes a reference point having a voltage associated with an output signal of the output component. A controller is configured for controlling the bandgap core component and the output component to switch between a low power consumption mode and a normal operation mode based on the voltage at the reference point. When the bandgap core component and the output component operate in the normal operation mode, the bandgap reference circuit outputs a stable voltage and has a first power consumption. When the bandgap core component and the output component operate in the low power consumption mode, the bandgap reference circuit has a second power consumption less than the first power consumption.

A high voltage logic circuit for high voltage system application comprises a first device layer formed from a first semiconductor material and comprises a low voltage logic circuit; and a second device layer formed from a second different semiconductor material and comprising one or more components of an additional circuit for generating a high voltage logic output from a low voltage logic input from the low voltage logic circuit; wherein the first and second device layers are integrally formed. Also, a logic circuit comprising: a low voltage logic input; a high supply voltage input; a circuit ground voltage input; a high voltage output; a first tail device made from a first semiconductor material; and a second tail device made from a second different semiconductor material; wherein the first and second tail devices are coupled, in series, between the high voltage output and the circuit ground voltage input; and wherein respective gates of the first and second tail devices are coupled, in parallel, to the low voltage logic input.

A power supply system for USB Power Delivery includes a current source drive circuit to control a power FET to regulate the supply of power along a power path. The current source drive circuit includes a cascode current source and a cascode protection circuit formed by a source follower and a feedback voltage divider. The source follower can be a transistor with its gate connected to a cascode node between upper- and lower-stage transistors of the cascode current source. The divider node of the voltage divider is connected to the gate of the lower-stage transistor. The current source drive circuit can operate within the gate-source voltage specifications of 30-volt DEPMOS devices, and can provide high output impedance to the gate of power FET and a current limit circuit during current limiting operation, without requiring an extra high-voltage mask during fabrication.

A semiconductor device includes: a drive transistor controlling current supply to a load; a current detector unit detecting a current of a sense transistor through which a current proportional to the current flowing through the drive transistor flows; a controller unit generating a pulse signal with a duty ratio corresponding to the detection result of the current detector unit; a voltage monitor monitoring whether a voltage of an external output terminal reaches a battery voltage; and a pre-driver performing charge and discharge to a control terminal of the drive transistor based on the pulse signal. The pre-driver performs the charge and discharge to the control terminal of the drive transistor at a first speed, when the voltage of the external output terminal reaches the battery voltage, and at a speed faster than the first speed, when the voltage of the external output terminal reaches the battery voltage.

Briefly, embodiments of claimed subject matter relate to comparison of a signal amplitude, such as a signal originating from a battery, for example, with a reference signal. A reference signal may be generated via body-biasing of one or more transistors, for example, which permit operation of the one or more transistors in a sub-threshold state, in which current through the one or more transistors comprises an exponential relationship to an applied voltage. Thus, at least in particular embodiments, detection of low battery voltage or battery overvoltage may be performed utilizing only a very small amount of electrical power.

A metal oxide semiconductor field effect transistor (MOSFET) based voltage regulator circuit includes a first resistor, a second resistor, and a first MOSFET. A first gate terminal of the first MOSFET is connected to a second terminal of the first resistor and a first terminal of the second resistor. A first drain terminal of the first MOSFET is connected to a second terminal of the second resistor and a first output terminal of the voltage regulator circuit. The first MOSFET receives an input supply voltage at the first gate terminal of the first MOSFET, via the first resistor. The first MOSFET provides a first constant output voltage at the first output terminal based on a change in the input supply voltage.

A buffer stage includes a control circuit. The control circuit includes a voltage generator, a voltage-to-current converter, and a current-to-voltage converter. The voltage generator is configured to generate a compensation voltage. The voltage-to-current converter is configured to convert the compensation voltage into a compensation current. The current-to-voltage converter is configured to convert the compensation current into a recovery compensation voltage. The recovery compensation voltage is arranged for modifying an output voltage of the buffer stage.

Briefly, embodiments of claimed subject matter relate to comparison of a signal amplitude, such as a signal originating from a battery, for example, with a reference signal. A reference signal may be generated via body-biasing of one or more transistors, for example, which permit operation of the one or more transistors in a sub-threshold state, in which current through the one or more transistors comprises an exponential relationship to an applied voltage. Thus, at least in particular embodiments, detection of low battery voltage or battery overvoltage may be performed utilizing only a very small amount of electrical power