Embodiments described herein present a new LDO design that eliminates the need for the sleep bias circuitry included in other systems. Further, the new LDO design can be biased with a small fraction of the operating current enabling the LDO to wake up substantially faster than previous LDO designs that include separate sleep circuitry. In some cases, the LDO can instantly (or faster than other LDOs) transition from a sleep mode to an operating mode enabling improved operation compared to prior LDOs. Furthermore, the new LDO design maintains a non-breakdown voltage across the transistors reducing the need to enter sleep mode to prevent transistors of the LDO from entering a breakdown region.

A detection circuit includes a first transistor coupled to a gate of a high power transistor, a second transistor whose source is coupled to a drain of the first transistor, a first voltage divider coupled to a source of the first transistor, and a second voltage divider coupled to the source of the second transistor. The first transistor is configured to generate a first transistor output voltage representative of a gate voltage of the high power transistor shifted based on a first gate-to-source voltage of the first transistor. The second transistor is configured to generate a second gate-to-source voltage substantially equal to the first gate-to-source voltage. The first divider is configured to divide the first transistor output voltage by a first factor. The second divider is configured to divide the second gate-to-source voltage by a second factor correlated with the first factor.

The present disclosure relates to the field of analog integrated circuit technology. A digital and analog mixed signal control circuit for eliminating a degenerate metastable state of a self-biased bandgap reference circuit utilizes a digital-to-analog converter module with low-power consumption and flexibly customized accuracy as needed, a delay switch, and a non-volatile memory cell to directly control and clamp a circuit node at the degenerate metastable state in the bandgap reference circuit module, and to release the clamping after a certain delay. Such control mechanism effectively prevents the self-biased bandgap reference circuit with an operational amplifier from entering the degenerate metastable state, and enhance robustness of the circuit, such that the reference circuit is capable of starting normally under various conditions, which improves the performance and yield of the products.

For example, a constant voltage generating circuit includes a first transistor and a second transistor, a first resistor configured to be connected between the gate and the source of the first transistor, a second resistor configured to pass a current with a value equal to that of the current flowing through the first resistor. A first constant voltage is generated by using the difference between the gate-source voltages of the first and second transistors and the terminal-to-terminal voltage across the second resistor.

A memory device comprises memory cells, a first regulator, a second regulator, a first switch, a second switch and capacitor coupling switches. The first regulator comprises a first capacitor, and generates a first voltage at a first node connected to a first subset of the memory cells, to provide the first voltage to the first subset. The second regulator comprises a second capacitor, and generates a second voltage at a second node. The first switch selectively couples the second node to a second subset of the memory cells, to provide the second voltage to the second subset. The second switch selectively couples the first node to the second subset to also provide the first voltage to the second subset. The capacitor coupling switches selectively couple the second capacitor in parallel to the first capacitor when the first switch is deactivated, and the second switch is activated.

Systems and methods as described herein may take a variety of forms. In one example, systems and methods are provided for a circuit for powering a voltage regulator. A voltage regulator circuit has an output electrically coupled to a gate of an output driver transistor, the output driver transistor having a first terminal electrically coupled to a voltage source and a second terminal electrically coupled to a first terminal of a voltage divider, the voltage divider having an second terminal electrically coupled to ground, and the voltage divider having an output of a stepped down voltage. A power control circuitry transistor has a first terminal electrically coupled to the voltage source, the power control circuitry transistor having a second terminal electrically coupled to the gate terminal of the output driver transistor, and the power control circuitry transistor having a gate terminal electrically coupled to a status voltage signal.

A switch circuit includes: a switch coupled to control an electrical parameter of a main circuit. A. PSRR of the main circuit is determined by the switch; a first driver configured to operably drive the switch, wherein the first driver is powered by a supply current; and a supply transistor configured to operably generate the supply current, wherein the supply transistor is biased in a subthreshold region, such that the PSRR of the main circuit is higher than a predetermined level within a predetermined frequency range.

Systems and methods are provided for generating a temperature compensated reference voltage. A temperature compensation circuit may include a proportional-to-absolute temperature (PTAT) circuit, and a complementary-to-absolute temperature (CTAT) circuit, with the PTAT circuit and the CTAT circuit including at least one common metal-oxide-semiconductor field-effect transistor (MOSFET) and being configured to collectively generate a reference voltage in response to a regulated current input. The PTAT circuit may be configured to produce an increase in magnitude of the reference voltage with an increase of temperature, and the CTAT circuit may be configured to generated a decrease in magnitude of the reference voltage with the increase of temperature, wherein the increase in magnitude of the reference voltage produced by the PTAT circuit is at least partially offset by the decrease in magnitude of the reference voltage produced by the CTAT circuit.

An electrical circuit for ensuring safe ramp-up and ramp-down of at least a regulated operating voltage, a reference voltage, and a reset signal for a consumer is described. The electrical circuit includes a voltage reference circuit and a voltage regulator. The voltage regulator is provided in order to furnish a regulated operating voltage, the voltage reference circuit is provided in order to be supplied with the regulated operating voltage furnished by the voltage regulator, and the voltage regulator is provided in order to obtain a reference voltage from the voltage reference circuit.

A semiconductor device may include a bandgap circuit that outputs a reference voltage. The semiconductor device may also include a startup circuit coupled to the bandgap circuit. The startup circuit may connect a voltage source to a node that corresponds to an output of the bandgap circuit in response to the bandgap circuit being initialized. The startup circuit may also disconnect the voltage source from the node in response to the reference voltage being greater than a threshold.