Abstract:
A circuit arrangement includes a first light emitting diode and a second light emitting diode emitting light of different colors arranged adjacent to each other for additive color mixing. A first and second controllable current sources are connected to the first and second light emitting diode, respectively, such that the load currents of the light emitting diodes depend on respective control signals received by the current sources. First and second sigma-delta modulators are connected to the first and second light emitting diodes, respectively, and provide bit-streams as control signals to the current sources. The mean value of each bit-stream corresponds to the value of an input signal of the respective sigma-delta modulator.
Abstract:
A regulating system comprises an input terminal for applying an input voltage, and an output terminal for providing an output voltage. A semiconductor element is connected between the input terminal and the output terminal and is operable to regulate the output voltage. A regulating signal generation circuit generates the regulating signal and comprises a current mirror arrangement including a first and second current mirror path, wherein a controlled current source is connected in series to the first current mirror path. The controlled current source induces a first current dependent on one of the output signals in the first current mirror path. A second current through the second current mirror path is dependent on the first current. A splitter circuit conducts the second current to the output terminal or to a reference potential, dependent on a load path voltage applied over the load path of the semiconductor element.
Abstract:
A regulating system comprising: an input terminal (K10) for applying an input voltage (Vin), an output terminal (K20) for providing an output voltage (Vout) and an output current (Iout), a semiconductor element (Q1) regulating the output voltage (Vout), which element has a load path which is connected between the input terminal (K1) and the output terminal (K2), and a control input to which a regulating signal (Ib1) is applied, a regulating signal generation circuit to generate the regulating signal (Ib1), which circuit has a current mirror arrangement (Q2, Q3) including a first and second current mirror path, wherein a controlled current source (Q4) is connected in series to the first current mirror path, which source induces a first current dependent on one of the output signals (Vout) in the first current mirror path, and wherein a second current (I2) through the second current mirror path is dependent on the first current (I1), a splitter circuit (20) which conducts the second current (I2) to the output terminal (K2) or to a reference potential (GND), dependent on a load path voltage (Vec1) applied over the load path of the semiconductor element (Q1).
Abstract:
The n-channel VDMOS transistor is formed in an n-type active region of an integrated circuit with junction isolation. To prevent over-voltages between source and gate which could damage or destroy the gate dielectric, a p-channel MOS transistor is formed in the same active region and has its gate electrode connected to the gate electrode of the VDMOS transistor, its source region in common with the source region of the VDMOS transistor, and its drain region connected to the p-type junction-isolation region. The p-channel MOS transistor has a threshold voltage below the breakdown voltage of the gate dielectric of the VDMOS transistor so that it acts as a voltage limiter.
Abstract:
A sensor of instantaneous power which is dissipated through a power transistor of the MOS type connected between the output terminal of a power stage and ground. It comprises a MOS transistor having its gate terminal connected to that of the power transistor, source terminal connected to ground, and drain terminal connected to a circuit node which is coupled to the output terminal by means of a current mirror circuit which includes a resistive element in its input leg. Connected to the circuit node is the base terminal of a bipolar transistor which is respectively connected, through a diode and a constant current generator between the output terminal and ground.
Abstract:
A system including an inter-chip communication system is disclosed. One embodiment includes a base chip including a base chip transceiver network. At least one chip is stacked on the base chip, the at least one stacked chip including a substrate, a cavity formed in the substrate, a first surface, and a stacked chip transceiver network disposed on the first surface adjacent to the cavity.
Abstract:
A short-circuit protection circuit, particularly for power transistors, contains a first circuit for mirroring the output current of a power transistor which is parallel-connected to the power transistor, and a second mirroring circuit which is series-connected to the first mirroring means and is adapted to emit a current which is correlated to the current mirrored by the first mirroring circuit, for comparison with a reference current. The result of the comparison determines the need to intervene or not on the power transistor. The short-circuit protection circuit may also contain a circuit for sensing the voltage drop across the power transistor which is parallel-connected to the power transistor and to the first mirroring circuit, in order to adjust minimum and maximum values of the current in output from the power transistor, as a function of the voltage that is present across the transistor.
Abstract:
An integrated amplifier includes a differential input stage including a first pair of bipolar junction transistors. A reference bias current generator biases the differential input stage with a reference bias current. A first and a second current mirror circuit drives a respective transistor of the first pair of bipolar junction transistors. Each of the first and second current mirror circuits includes a transistor having a base terminal connected to an intermediate node. An integrated resistor is connected to the intermediate node and is in series with the respective transistor of the first pair of bipolar junction transistors. The reference bias current of the differential input stage conducts through the integrated resistor. The reference bias current corresponds to a ratio between a base emitter junction voltage and a resistance of the integrated resistor. An output stage includes a second pair of bipolar junction transistors, which are controlled by a respective transistor of the first and second current mirror circuits.
Abstract:
A low frequency amplifier comprising, in series, a first input stage, an intermediate amplifying stage and a final stage. The intermediate amplifying stage comprises a capacitor which is discharged when the amplifier is disabled, and is charged to a predetermined bias value when the amplifier is operative. To prevent voltage peaks at the output of the amplifier during the transient interval between the disabled and operating condition of the amplifier, a second input stage is provided which is only turned on during the transient interval, and is connected to the capacitor to detect its voltage and charge it. During the transient interval, the final stage is disabled. Upon the capacitor reaching the predetermined charge value, the second input stage practically turns itself off, and is then disabled; and, at the same time, the first input stage and the final stage are enabled to turn on the amplifier.