Abstract:
An integrated semiconductor structure (500) comprises two homologous P-type regions (120 and 130) formed within an N-type epitaxial layer (110). A P-type region (510) formed in the portion of the epitaxial layer (110) disposed between the two P-type regions (120 and 130) includes within it an N-type region (520); this N region (520) is electrically connected to the P region (130) by means of a surface metal contact (530). The structure reduces the injection of current between the P region 120 and the P region 130, at the same time preventing any vertical parasitic transistors from being switched on.
Abstract:
A power semiconductor structure (200), in particular in VIPower technology, made from a chip of N-type semiconductor material (110), comprising a bipolar or field-effect vertical power transistor (125, 120, 110) having a collector or drain region in such N-type material (110); the semiconductor structure comprises a PNP bipolar lateral power transistor (210, 110, 220) having a base region in such N-type material (110) substantially in common with the collector or drain region of the vertical power transistor.
Abstract:
The purpose of the present invention is to protect the final transistor (PW) of a power actuator from short circuits and overloads with a completely integrated circuitry solution which would not influence the output impedance of the actuator and would permit having a limitation current constant and independent of the value of the output terminal of the actuator. A power actuator in accordance with the present invention incorporates a circuit for limitation of the maximum current delivered by the power transistor (PW) which comprises:
a network for detection of the current delivered by the power transistor (PW) which generates a first electrical signal proportional to said current, a reference network generating a reference electrical signal, and an operational amplifier (3) which compares the first electrical signal with the reference electrical signal and which tends to inhibit the power transistor if the current delivered exceeds a certain threshold value and whose output terminal is coupled to the reference network in such a manner that the reference electrical signal depends on the voltage present at the amplifier output.
Abstract:
The amplifier described has an output stage constituted by an npn transistor (Q1) and a pnp transistor (Q2) in a push-pull arrangement, and a driver stage. The latter comprises a current-mirror circuit having, in its input branch, a pnp transistor (Q3) in series with a first constant-current generator (G1) and, in its output branch, an npn transistor (Q4), and two complementary transistors (Q5 and Q6) of which the collectors are connected together to the output terminal (OUT) and the bases are connected together to the input terminal (IN) of the amplifier. The emitter of the pnp transistor (Q5) of the driver stage is connected to the positive terminal (vdd) of the supply by means of a second constant-current generator (G2) and to the base of the npn transistor (Q1) of the output stage, and the emitter of the npn transistor (Q6) of the driver stage is connected to the negative terminal (gnd) of the supply by means of the npn transistor (Q4) of the output branch of the current-mirror circuit and to the base of the pnp transistor (Q2) of the output stage. The amplifier has a very low or zero offset ( Vos = Vout-Vin ).
Abstract:
The present invention relates to a circuit for protecting from overload currents an electronic power device having at least first and second terminals and at least one control terminal, which circuit comprises:
at least one voltage-generating circuit means (CSVG) for generating a reference voltage (Vref) having a predetermined pattern, said voltage-generating circuit means (CSVG) having at least a first terminal connected to the first terminal of the power device (POWER) and at least a second terminal which is coupled to the second terminal of the power device (POWER) through a sensor (Rs); at least one comparator (C1) for comparing the reference voltage (Vref) with a voltage (Vrs) present across the sensor (Rs), the comparator (C1) having at least one output terminal and at least first and second input terminals, the last-mentioned terminals being respectively connected to a third terminal of the voltage-generating circuit means (CSVG) and the second terminal of the power device (POWER); at least one current limiter (Q1) having at least a first terminal connected to the control terminal of the power device (POWER), at least a second terminal connected to the second terminal of the voltage-generating circuit means (CSVG), and at least one control terminal connected to the output terminal of the comparator (C1).
Abstract:
The present invention relates to an electronic device integrated monolithically on a semiconductor material comprising a substrate (1) having a first conductivity type in which are formed a first (2) and second diffusion regions (3) of a second conductivity type with said substrate (1) and said first (2) and second (3) diffusion regions including respectively a base region, a collector region and an emitter region of a transistor (Tp1) and characterized in that in the second diffusion region (3) is formed a third diffusion region (8) having conductivity of the first type to provide in said second diffusion region (3) a resistive path (R) placed in series with the emitter region of the transistor (Tp1) while backfeeding it negatively and taking it to saturation with a resulting reduction of its current gain and limitation of the maximum current due thereto.
Abstract:
A monolithic high-voltage semiconductor device with integrated edge structure of the type provided on a semiconductor material substrate (2) having a first conductivity type and on which are grown a first (5) and second (6) epitaxial layer having the same conductivity type. The device (1) comprising also a type PN junction (3) including a first diffuse region (4) having a second conductivity type provided inside the first (5) and second (6) epitaxial layers and an edge structure (10) also provided inside the epitaxial layers (5) and (6) and adjacent to the junction (3) including a termination region (12) having a second conductivity type. The device (1) is characterized in that the edge structure (10) also comprises at least one thin region (13) having a second conductivity type located between the junction (3) and the termination region (12).
Abstract:
A sense and protection circuit against short circuits for digital outputs, comprising a logic gating circuit of the exclusive OR type (EX1) which has a first input terminal connected to a signal input node (IN) and an output terminal which is connected to an input terminal of a signal level shifter output stage (B). A second logic gating circuit of the exclusive OR type (EX2) has a first input terminal connected to the input node (IN) and a second input terminal connected, through an inverting circuit (IN1), to an output terminal (OUT) of the output stage (B). A second input terminal of the first logic gate circuit is coupled to an output terminal of the second logic gate circuit through a comparator circuit (SCH1) and a delay circuit means (C,R,D).
Abstract:
The present invention relates primarily to a pulse generator (GEN) having an input (ID) and two outputs (OR,OS) at which to generate respectively a pulse in relation to a edge of a different type at input. The generator provides two distinct logic circuit blocks of the sequential type hence mutually independent for generation of the pulses at the two outputs. In this manner it is possible to easily control the characteristics of the pulses. In addition, if two blocks are connected with appropriate and simple logic networks (G3,G4) it is possible in the generation phase to impose conditions between the pulses at the two outputs in a simple manner and with a certain freedom.
Abstract:
The invention relates to a circuit for detecting an overvoltage in an electrical load (Z1) inserted with a first and a second terminal between a feed line (AL) and a control switch (S), the circuit having an output voltage (Vout) at an output terminal (OUT) and comprising:
at least one first threshold comparator (C1) having a first input terminal held at a first reference voltage (E1), a second input terminal connected to the feed line (AL) and an output terminal, at least one second threshold comparator (C2) having a first input terminal held at a second reference voltage (E2), a second input terminal connected to a second terminal of the electrical load (Z1), and an output terminal, at least one output transistor (T1) inserted with a first and a second terminal between the feed line (AL) and an output terminal (OUT) of the circuit (1), the transistor (T1) being controlled by at least one logic block (D) having inputs connected to the outputs of the threshold comparators (C1) and (C2), at least one feedback block (R) inserted with an input terminal and an output terminal respectively between the output terminal (OUT) of circuit (1) and a further input terminal to the logic block (D).