Abstract: A power supply controller (20) is configured to operate in a test mode that facilitates measuring the value of an output signal of an error amplifier (36) of the power supply controller (20).

Abstract: A selected bandgap reference (11) of a voltage generator (10) is operated at a duty cycle that is less than one hundred percent. The seclectable bandgap reference (11) has at a high current consumption when enabled and a low current consumption when disabled. The output voltage of the selectable bandgap reference (11) is stored on a storage element (13) when the selectable bandgap reference (11) is enabled. A high impedance amplifier (16) receives the stored voltage and generates the reference voltage.

Abstract: In one embodiment, a voltage protection circuit uses two back-to-back transistors to receive an unprotected voltage and form a protected voltage.

Abstract: A selected bandgap reference (11) of a voltage generator (10) is operated at a duty cycle that is less than one hundred percent. The seclectable bandgap reference (11) has at a high current consumption when enabled and a low current consumption when disabled. The output voltage of the selectable bandgap reference (11) is stored on a storage element (13) when the selectable bandgap reference (11) is enabled. A high impedance amplifier (16) receives the stored voltage and generates the reference voltage.

Abstract: A voltage regulator (15) utilizes a first current source (31) and a second current source (32) to form a reference current to limit current flow through an output transistor (13) during a start-up period. After the start-up period expires, the first current source (31) is disabled and the voltage regulator (15) controls the output voltage produced by the output transistor (13) instead of controlling the current flow through the output transistor (13).

Abstract: A voltage regulator (15) utilizes a first current source (31) and a second current source (32) to form a reference current to limit current flow through an output transistor (13) during a start-up period. After the start-up period expires, the first current source (31) is disabled and the voltage regulator (15) controls the output voltage produced by the output transistor (13) instead of controlling the current flow through the output transistor (13).

Abstract: The present invention relates to a BICMOS technology comparator including: a first stage with differential inputs capable of operating with input voltages which are, in the common mode, lower than a positive supply potential minus a first threshold voltage, the first stage controlling a first bipolar output transistor; a second stage with differential inputs for operating with input voltages which are, in the common mode, higher than a negative supply potential plus a second threshold voltage, the second stage controlling a second bipolar output transistor and the output transistors being connected in series between two terminals at the positive and negative supply potentials, and a midpoint of their series connection forming an output terminal of the comparator; and circuitry for controlling the differential stages according to the voltages applied on their inputs.

Abstract: The low temperature-corrected constant voltage generator device includes a reference voltage generator, an amplifier connected between the reference voltage generator and an output terminal and a voltage divider connected to an input of the amplifier in order to supply a feedback voltage to the amplifier. The divider includes at least one first resistor in series with an element having, at least in the low temperature range, an impedance with a temperature dependence behavior different from that of the first resistor, to supply a lower feedback in the low temperature range.

Abstract: A low supply voltage comparator in BICMOS technology includes: a first stage (1) with differential inputs (2,3) including, among others, two MOS transistors (MP1, MP2) of a first channel type controlling a first output bipolar transistor (T's); a second stage with differential inputs (2, 3) including, among others, two MOS transistors (MN1, MN2 (of a second channel type controlling a second output bipolar transistor (T's), the output transistors being mounted in series between two (A, M) terminals of application of respectively positive (Vdd) and negative (Vss) supply voltages; a switch (13' 13') for selecting one of the output transistors according to the common mode level of the input voltages with respect to the supply voltages; and a controller (15) for controlling the switch in all or nothing.

Abstract: The present invention relates to a BICMOS technology comparator including: a first stage with differential inputs capable of operating with input voltages which are, in the common mode, lower than a positive supply potential minus a first threshold voltage, the first stage controlling a first bipolar output transistor; a second stage with differential inputs for operating with input voltages which are, in the common mode, higher than a negative supply potential plus a second threshold voltage, the second stage controlling a second bipolar output transistor and the output transistors being connected in series between two terminals at the positive and negative supply potentials, and a midpoint of their series connection forming an output terminal of the comparator; and circuitry for controlling the differential stages according to the voltages applied on their inputs.

Abstract: A band-gap type constant voltage generating device includes a current source to generate a current increasing linearly as a function of the temperature, and a first current mirror to copy the current in the current source into an "output" leg. The output leg according to the invention comprises at least one junction with a voltage at its terminals that reduces linearly with the temperature, and a load resistance connected in series with the junction. The band-gap type constant voltage generator may be used as voltage reference.

Abstract: The start-up aid circuit is connected to a plurality of current sources. The start-up aid circuit is common to all the current sources and supplies a start-up current to each current sources when the current sources are operating in a transient operating state following power-up of the apparatus. The circuit also inhibits the start-up aid circuit when all the current sources have reached an operating state described as stationary. The circuit may be applied to the power supply of microprocessors and electronic equipment.

Abstract: A voltage regulator for powering a load with a predetermined temperature-stable voltage, including an output stage, a terminal of which provides a current to the load, at a reference voltage; and a current source including a first branch formed of transistors and of a first resistor connected in series between two supply terminals, and a second branch formed of transistors connected in series between the two supply terminals, the output stage including a bipolar transistor connected as a current mirror with a bipolar transistor of the second branch, and the two transistors of the current source are crossed.

Abstract: A power supply voltage monitoring device includes a constant voltage generator, a comparator to compare the power supply voltage with a reference voltage output by the constant voltage generator and to control the state of an output terminal. The device also comprises a delay circuit to put the output terminal into a predetermined state (low) for a predetermined duration exceeding the duration of the transient conditions, while the voltage generator is being put into operation. The power supply voltage monitoring device may typically be applied in microprocessor equipment.