A power supply circuit that outputs via an output terminal an output voltage based on an input voltage applied to an input terminal includes: an inserted transistor of an N-channel depletion type inserted between the input terminal and an internal supply power terminal; and a regulator configured to generate the output voltage by using as a supply voltage a voltage applied to the internal supply power terminal. The gate of the inserted transistor is connected to the output terminal.

A voltage regulator circuit includes a bias circuit having an input and an output. The input of the bias circuit is coupled to an input voltage supply rail. A Zener diode has a cathode coupled to the output of the bias circuit. A resistor network is coupled to the output of the bias circuit. The resistor network includes a first circuit path, which includes a first resistor, connected in parallel with the Zener diode and a second circuit path, which includes a second resistor, coupled between the output of the bias circuit and a node. A current control circuit is coupled to the bias circuit and the resistor network. An output stage has an input and an output. The input of the output stage is coupled to the node.

An apparatus, a method, and an integrated circuit for a providing a temperature-compensated Zener reference are disclosed. In accordance with at least one embodiment, the apparatus comprises a proportional-to-absolute-temperature (PTAT) current source; a complementary-to-absolute-temperature (CTAT) current source; and a Zener diode, with the PTAT current source coupled to a first Zener diode terminal of the Zener diode, the CTAT current source coupled to the first Zener diode terminal of the Zener diode, and the PTAT current source providing a PTAT current and the CTAT current source providing a CTAT current, wherein the PTAT current and the CTAT current are combined for provide a temperature-compensated bias current.

A power supply conversion circuit is provided, which includes: a first voltage clamping module configured to decrease an input voltage to a preset low voltage; a boost module configured to increase the input voltage or the preset low voltage to a target voltage; a second voltage clamping module configured to maintain the target voltage within a preset voltage range; a filter module configured to filter out ripples in the target voltage; and at least one output module, each of which is configured to supply power to a load. Compared with a conventional LDO integrated circuit, the circuit can provide multiple output power supplies, and it is only required to additionally arrange one field effect transistor for one more output power supply. Therefore, the power supply conversion circuit has a simple structure, is expandable easily and is applicable to an analog integrated circuit requiring multiple output power supplies.

A first terminal receives a first DC voltage. A switch selectively couples the first terminal to a second terminal providing an output. A control circuit selectively actuates the switch in response to a comparison of the first DC voltage to a second DC voltage. A low-dropout (LDO) linear voltage regulator, connected between the first and third terminals, operates to provide the second DC voltage from the first DC voltage.

An apparatus, a method, and an integrated circuit for a providing a temperature-compensated Zener reference are disclosed. In accordance with at least one embodiment, the apparatus comprises a proportional-to-absolute-temperature (PTAT) current source; a complementary-to-absolute-temperature (CTAT) current source; and a Zener diode, with the PTAT current source coupled to a first Zener diode terminal of the Zener diode, the CTAT current source coupled to the first Zener diode terminal of the Zener diode, and the PTAT current source providing a PTAT current and the CTAT current source providing a CTAT current, wherein the PTAT current and the CTAT current are combined for provide a temperature-compensated bias current.

A switching circuit with switches between a charging path and a low-impedance active path. The charging path comprises a zener diode substantially in parallel with a charging capacitor. Current flows through the charging path when the circuit is powered on and a power supply charges the charging capacitor while current flows through the charging path. The low-impedance bypass path comprises a switch that remains closed until a voltage across the charging capacitor exceeds a threshold voltage. The switch opens when the charging capacitor exceeds the threshold voltage.

A compensation circuit configured for coupling to a voltage source and a reference circuit. The voltage source is configured for supplying a supply voltage to the compensation circuit and the reference circuit. The reference circuit includes a first circuit node and a reference output electrically coupled to the first circuit node for outputting a reference signal having a constant reference amplitude. The compensation circuit includes a transient converter for converting a first transient perturbation of the supply voltage into a first compensation electrical signal proportional to said first transient perturbation, and an adder coupled to the transient converter for adding the first compensation electrical signal to an electrical signal at the first circuit node with a first polarity opposite to a disturbance polarity of a disturbance of the electrical signal in response to the first transient perturbation.

An integrated circuit includes a voltage reference circuit including a Zener diode having a first terminal coupled to a first node and a second terminal coupled to a first voltage supply terminal. A proportional to absolute temperature (PTAT) circuit is coupled at the first node and configured to generate a PTAT current. A PTAT compensation circuit is coupled at the first node. The PTAT compensation circuit includes a first current mirror having a first branch coupled at the first node.

A switch apparatus is provided. The switch apparatus includes a signal control switch, a switch circuit, a blocking capacitor and a surge current dissipation circuit. The signal control switch and the switch circuit are respectively controlled by a first control signal and a second control signal to be turned on or off. The blocking capacitor is serially coupled between the switch circuit and a reference voltage end. The surge current dissipation circuit includes a Zener diode circuit or at least one diode circuit, and the at least one diode circuit has one or more diodes coupled in series. The one or more diodes coupled in series are coupled between two ends of the surge current dissipation circuit according to a first polarity direction.