摘要:
A protection circuit of a diagnostic output line (K-line) of a control unit for protection of the control unit in the event of a ground disconnection or of a “below ground” condition is provided. The diagnostic output line includes a first interface DMOS transistor with a source connected to ground and a drain coupled to the diagnostic output line through a second DMOS transistor with a source connected to the output line and a drain connected to the source of the first DMOS transistor. The protection circuit also includes a comparator for the voltage of the diagnostic output line with the potential of the ground node, and a two-input logic gate, whose output controls a current generator forcing a current, limited by a resistor, on the diagnostic output line.
摘要:
A system for diagnosing a driver and detecting circuit anomalies therein includes: voltage comparator circuits for generating diagnostic logic signals, each of which indicates the existence of a corresponding type of anomaly; and a coding circuit to receive the diagnostic logic signals and to output information relating to an overall operating state of the driver. The coding circuit includes a first portion to provide at its output first logic input signals indicating the last anomaly to occur since a system reset operation. The coding circuit also includes a second portion for coding the first logic input signals. The second portion includes a sequential logic network to receive the first logic input signals and at least one second logic signal indicating the current operating phase of the driver. The second portion provides, as a function of the first and second logic signals, a stable internal state to determine the output information in the form of an N bit coded word. The N bit coded word is representative of the occurrence of an anomaly, of an absence of an anomaly in the current operating phase, or of an absence of an anomaly in any operating phase.
摘要:
A voltage-regulator circuit with a low voltage drop uses a DMOS power transistor driven by a charge pump. The control circuit includes two feedback loops: a first feedback loop having a high gain and accuracy but low response speed, and a second feedback loop having a wide passband and fast response speed, but low gain.
摘要:
A differential amplifier provides a high common mode rejection while maintaining substantially unchanged the input dynamic range. The differential amplifier includes a comparator having inputs to which are applied the two input signals, which are also applied to an operational amplifier, so that the comparator outputs a signal whose sign is indicative of the sign of the difference between the two input signals. The output of the operational amplifier is feedback to one of the inputs of the operational amplifier through a current mirror. This feedback signal is switched between the non-inverting input of the operational amplifier and the inverting input of the operational amplifier. The switching of the feedback signal ensures negative feedback, and is dependent upon the sign of the difference detected by the comparator.
摘要:
A temperature control system and method for integrated circuits, particularly those having a plurality of channels or power devices. The temperature control system for an integrated circuit includes at least a heat generating device; a sensor element providing a signal correlated to the working conditions of said the heat generating device such as a signal proportional to the dissipated power of the heat generating device; an elaboration circuit of the signal correlated to the working conditions of the heat generating device; and a turning off circuit of said at least a heat generating device responsively to a signal of said elaboration circuit.
摘要:
A circuit arrangement comprising an input amplifier stage (31) with two inputs (36, 37) and an output (34) being connectable to an input (35) of an output amplifier stage (32). The circuit furthermore comprises a comparator (33) with a first input (41), a second input (42) and a comparator output (44), a feedback capacitor (43) connected to an offset tuning input (45) of the input amplifier stage (31), and a plurality of switches (S1, S2) that are controllable by switching signals (V1, V2) to allow the circuit to be switched from a first phase to a second phase. During the first phase (1), the output (34) and the input (35) are separated by a first one of the switches (S2) and the two inputs (36, 37) are connected via a second one of the switches (S1). The first input (41) of the comparator (33) is connected to the output (34) of the input amplifier stage (31) and the second input (42) of the comparator (33) is connected to the input (35) of the output amplifier stage (32) such that via the comparator output (44) a charge on the feedback capacitor (43), and hence the voltage at the offset tuning input (45) is altered and an offset of the input amplifier stage (31) is corrected.
摘要:
Non linear circuit for open load control in Low-Side Driver type circuits, including at least two power transistors, scaled according to an area ratio 1 to M, with M>1, wherein the power transistor having the smaller area is controlled by a circuit input signal while the transistor having the larger area is controlled by an output value of an AND type logic gate, managed by a control circuit, that is regulated by the output value of a voltage sensor, placed in parallel with the power transistor having the larger area, and by the output value of a current sensor, placed in series with the power transistor having the smaller area, so that, when a current flowing in the power transistor having the smaller area is less than a predetermined value of the threshold current, the control circuit signals the open load on an output pin.
摘要:
Apparatus (80) comprising an input stage (61) with an NMOS transistor doublet having a first differential input for receiving input signals, and a PMOS transistor doublet having a second differential input for receiving input signals. The apparatus (80) further comprises switching means for receiving and selectively directing analog input signals either to the first differential input or to the second differential input. The means are controlled by a switching signal ((,p in a manner to keep the ratio of the transconductance of the NMOS transistor doublet and the transconductance of the PMOS transistor doublet constant.
摘要:
A circuit for the generation of an electrical signal of constant duration comprises a capacitor, a constant current generator for charging the capacitor, and a voltage comparator to compare the voltage present at the terminals of the capacitor with a reference voltage. The voltage comparator supplies at an output a digital signal dependent upon the voltage across the capacitor. The constant current generator comprises a transistor biased with a voltage between gate and source obtained as the difference between the sum of two gate-source voltages of two transistors and a gate-source voltage of another transistor.
摘要:
Apparatus (80) comprising an input stage (61) with an NMOS transistor doublet having a first differential input for receiving input signals, and a PMOS transistor doublet having a second differential input for receiving input signals. The apparatus (80) further comprises switching means for receiving and selectively directing analog input signals either to the first differential input or to the second differential input. The means are controlled by a switching signal (φ,φ) in a manner to keep the ratio of the transconductance of the NMOS transistor doublet and the transconductance of the PMOS transistor doublet constant.