Disclosed herein is an apparatus that includes a first reference voltage generator configured to generate a first voltage, a second reference voltage generator configured to generate a second voltage, a detection circuit configured to compare the first voltage with the second voltage to generate a selection signal, and a selection circuit configured to select one of the first and second voltages responsive to the selection signal. The detection circuit is configured to have a hysteresis property in changing a state of the selection signal.

Disclosed herein is an apparatus that includes a first reference voltage generator configured to generate a first voltage, a second reference voltage generator configured to generate a second voltage, a detection circuit configured to compare the first voltage with the second voltage to generate a selection signal, and a selection circuit configured to select one of the first and second voltages responsive to the selection signal. The detection circuit is configured to have a hysteresis property in changing a state of the selection signal.

A voltage converter includes an inductor, a transistor, a comparator, an error amplifier, and a slope generator circuit. The transistor has a control input and first and second transistor current terminals. The first current terminal is coupled to the inductor. The comparator has first and second comparator inputs and a comparator output. The comparator output is usable to control the transistor's control input. The error amplifier has an error amplifier input and an error amplifier output. The error amplifier output is coupled to the first comparator input. The slope generator circuit is coupled to at least one of the first or second comparator inputs. The slope generator circuit is configured to generate a slope compensation current which, during at least a portion of each cycle of operation of the voltage regulator, varies approximately exponentially with respect to time.

A voltage converter includes an inductor, a transistor, a comparator, an error amplifier, and a slope generator circuit. The transistor has a control input and first and second transistor current terminals. The first current terminal is coupled to the inductor. The comparator has first and second comparator inputs and a comparator output. The comparator output is usable to control the transistor's control input. The error amplifier has an error amplifier input and an error amplifier output. The error amplifier output is coupled to the first comparator input. The slope generator circuit is coupled to at least one of the first or second comparator inputs. The slope generator circuit is configured to generate a slope compensation current which, during at least a portion of each cycle of operation of the voltage regulator, varies approximately exponentially with respect to time.

A reference voltage circuit (1) includes a PTAT voltage generation circuit (20) that generates a voltage with a positive temperature coefficient, a CTAT voltage generation circuit (10) that generates a voltage with a negative temperature coefficient, and a temperature characteristic adjustment circuit (30) that generates a voltage for adjusting temperature characteristics. The reference voltage circuit outputs a reference voltage (VOUT) formed by calculation based on the output of the PTAT voltage generation circuit, output of the CTAT voltage generation circuit, and output of the temperature characteristic adjustment circuit.

A reference voltage circuit (1) includes a PTAT voltage generation circuit (20) that generates a voltage with a positive temperature coefficient, a CTAT voltage generation circuit (10) that generates a voltage with a negative temperature coefficient, and a temperature characteristic adjustment circuit (30) that generates a voltage for adjusting temperature characteristics. The reference voltage circuit outputs a reference voltage (VOUT) formed by calculation based on the output of the PTAT voltage generation circuit, output of the CTAT voltage generation circuit, and output of the temperature characteristic adjustment circuit.

Provided are an LDO, an MCU, a fingerprint module and a terminal device. The LDO includes: a reference voltage generating circuit and a source follower connected to the reference voltage generating circuit. The reference voltage generating circuit is used to generate a reference voltage that changes with temperature to offset a voltage change caused by a voltage between a first terminal and a second terminal of the source follower changing with time, so that an output voltage of the second terminal of the source follower does not change with temperature. The LDO omits an operational amplifier EA and a resistor divider feedback network in the prior art, which not only has a simple circuit structure, but also can achieve ultra-low power consumption.

Provided are an LDO, an MCU, a fingerprint module and a terminal device. The LDO includes: a reference voltage generating circuit and a source follower connected to the reference voltage generating circuit. The reference voltage generating circuit is used to generate a reference voltage that changes with temperature to offset a voltage change caused by a voltage between a first terminal and a second terminal of the source follower changing with time, so that an output voltage of the second terminal of the source follower does not change with temperature. The LDO omits an operational amplifier EA and a resistor divider feedback network in the prior art, which not only has a simple circuit structure, but also can achieve ultra-low power consumption.

A control circuit for a voltage regulator has an energy regulation circuit and a switching control circuit. The energy regulation circuit provides a regulation signal based on an output voltage, an output current, and a maximum energy reference. The maximum energy reference decreases with increasing of an ambient temperature and increases with decreasing of the ambient temperature. The switching control circuit provides a switching control signal based on the regulation signal to turn ON and turn OFF at least one switch of a plurality of switches of the voltage regulator, such that the output voltage and the output current satisfy a first relationship when the ambient temperature equals a first temperature value, and the output voltage and the output current satisfy a second relationship when the ambient temperature equals a second temperature value.

A control circuit for a voltage regulator has an energy regulation circuit and a switching control circuit. The energy regulation circuit provides a regulation signal based on an output voltage, an output current, and a maximum energy reference. The maximum energy reference decreases with increasing of an ambient temperature and increases with decreasing of the ambient temperature. The switching control circuit provides a switching control signal based on the regulation signal to turn ON and turn OFF at least one switch of a plurality of switches of the voltage regulator, such that the output voltage and the output current satisfy a first relationship when the ambient temperature equals a first temperature value, and the output voltage and the output current satisfy a second relationship when the ambient temperature equals a second temperature value.