A signal generating device includes: a first circuit arranged to generate a first current to a first bipolar junction transistor therein; a second circuit coupled to the first circuit via an output terminal for generating a second current to a second BJT therein; and a first control circuit coupled to the first circuit and the second circuit, for generating a first adjusting current and a second adjusting current to the first circuit and the second circuit for adjusting the first current and the second current such that the first circuit and the second circuit outputs a temperature-dependent signal on the output terminal.

A signal generating device includes: a first circuit arranged to generate a first current to a first bipolar junction transistor therein; a second circuit coupled to the first circuit via an output terminal for generating a second current to a second BJT therein; and a first control circuit coupled to the first circuit and the second circuit, for generating a first adjusting current and a second adjusting current to the first circuit and the second circuit for adjusting the first current and the second current such that the first circuit and the second circuit outputs a temperature-dependent signal on the output terminal.

A front-end module comprises a low-dropout (LDO) voltage regulator, a reference current generator, and a power amplifier. The LDO voltage regulator, reference current generator, and power amplifier are integrated on a first semiconductor die.

A power on reset circuit comprises terminals for reference and supply potentials and a voltage divider coupled therebetween. First and second transistors of a bandgap circuit are resistively coupled to the reference potential terminal and have bases connected to the voltage divider. Current mirrors couple the collectors of the first and second transistors to an output terminal providing an output signal indicating a power on reset condition. A first compensation transistor is coupled between the collector of one of the transistors and the reference potential terminal, and a second compensation transistor is coupled between the output terminal and the reference potential terminal to compensate the effect of parasitic substrate currents in response to an external interference.

A diode voltage from a diode circuit can be combined with a proportional to absolute temperature (PTAT) voltage generated by a PTAT circuit to determine a temperature sensor voltage. This temperature sensor voltage may correspond to a temperature of a circuit or a localized temperature. By determining the temperature sensor voltage using a combination of a PTAT voltage and diode voltage, it is possible to remove or a PTAT circuit used to generate a bandgap voltage, which may shrink the temperature sensor and increase the accuracy of the temperature sensor circuit.

The disclosure provides a temperature compensation circuit that generates a temperature-compensated current and an integrated semiconductor circuit using the temperature compensation circuit. The temperature compensation circuit includes: a first PTAT current source which has a first emitter area ratio and generates a first current, the first current having a first temperature coefficient proportional to the absolute temperature; a second PTAT current source which has a second emitter area ratio and generates a second current, the second current having a second temperature coefficient proportional to the absolute temperature; an adjustment circuit which adjusts the current generated by the first PTAT current source; and a differential circuit which outputs the difference between the current adjusted by the adjustment circuit and the current generated by the second PTAT current source.

A voltage regulator comprising a reference current generator coupled between a supply terminal and a reference terminal and configured to provide a reference current that is independent of an operating range of a supply voltage; and a regulator stage comprising: a current terminal configured to receive the reference current; a NMOS transistor having: a gate coupled to the current terminal; a drain coupled to the supply terminal; and a source coupled to an output terminal; a voltage reference circuit for providing a regulated output voltage coupled between the output terminal and the reference terminal, the voltage reference circuit comprising an output resistor coupled in series with a conduction channel of an output bipolar transistor arranged in a diode-connected configuration; an input bipolar transistor having: a conduction channel coupled between the current terminal and the reference terminal; and a base terminal coupled to a base terminal of the output bipolar transistor.

A bandgap reference starting circuit with ultra-low power consumption includes a current generating unit and a first bias voltage generating unit respectively connected with a power supply voltage. The current generating unit generates an nA-level current and a starting voltage for the first bias voltage generating unit. The first bias voltage generating unit is started and generates a first bias voltage according to the starting voltage, and output the first bias voltage to a bandgap reference circuit to start up the bandgap reference circuit. The starting circuit can normally start up a bandgap reference circuit of nA level, and has an nA-level working current, thereby reducing power consumption and saving the cost.

A bandgap current reference circuit includes a bandgap core circuit and an error amplifier. The bandgap core circuit is configured to generate a zero temperature coefficient bandgap current. The bandgap core circuit includes a bipolar transistor. The bipolar transistor is configured to pass a current that is proportional to absolute temperature (PTAT current). The error amplifier is coupled to the bandgap core circuit and includes a bipolar differential input pair. The bipolar differential input pair is configured to ensure that the PTAT current is flowing in the bipolar transistor.

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.