Marelli Autronica

Other

Sgs-thomson Microelectronics S.r.l.

Cselt-centro Studi E Laboratori Telecomunicazioni S.p.a.

Valerio Giorgetta

Marcello Boella

Vanni Poletto

Marco Siligoni

Stefano Sgatti

Giampietro Maggioni

Franco Salerno

Mario Sartori

Andrea Milanesi

Guido Ghisio

Stefania Chicca

Paolo Mastella

Mirco Contucci

Gianluigi Morello

Vanni Poletta

Paola Redivo

Sergio Vigna

Yves LeGrand

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.

System for the complete diagnosis of a driver

A circuit comprises a measurement resistor in series with a heater, a detector circuit for providing a signal indicative of the current flowing in the resistor, switching devices for controlling the connection of the heater to a voltage source and the connection of the measurement resistor in the supply circuit comprising the source and the heater, and a control unit arranged to drive the switching devices in a manner such that each time the heater is activated, the measurement resistor is kept disconnected from the supply circuit of the heater for a predetermined period of time and the measurement resistor is then connected in the supply circuit of the heater.

Heater control circuit

The circuit includes sensors for supplying electrical signals indicative of the current flowing in the field winding of the generator in operation and a control circuit operatively connected to the sensors. The control circuit is arranged to control the transistor which drives the field winding so that the voltage at the battery terminals remains substantially constant with variations in the current supplied to the battery by the generator.

Voltage-regulator circuit for a system for recharging the battery of a

The interface circuit described comprises a plurality of control stages, each of which can detect and indicate a short-circuit in the corresponding load or the associated power transistor. In particular, the interface circuit is arranged to disable a transistor permanently when short-circuits occur repeatedly in the load in order to prevent damage to the transistor.

Circuit for interfacing between a microprocessor and a plurality of

During the piloting of the load, the current intensity and the voltage present in the load are monitored by the comparison of their values with a current threshold and with a window of permissible voltage values. When the voltage is outside the window of permissible values and/or the current falls below its threshold, a fault message is generated and the nature of the fault (open load, short circuit to earth, short circuit to the supply voltage) is also identified by the emission of a corresponding signal of a diagnostic nature. The identification of the faulty stage or stages is also provided for in the case of a circuit including several stages in parallel.

Electrical circuit, particularly an electronic power circuit for motor

A network for supplying identical biasing voltages and programmable direct currents to a plurality of mutually similar transceivers, connected across respective transmission lines, is integrated with the associated transceivers in a common semiconductor body and comprises a generator of fixed reference voltage determined by the band gap of the semiconductor. The reference voltage is applied in parallel to the bases of several NPN transistors emitting the same biasing voltage as a result thereof. This reference voltage also drives an NPN pilot transistor lying in series with an external resistor through which it draws a small programmed current. Through two cascaded amplification stages formed by NPN transistors operating in the ECL mode, with the second stage designed as a multiple-output current mirror, the programmed current is stepped up to provide the several direct currents required by the associated transceivers.

Biasing network for multifunction bipolar integrated system

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Turin, Italy

Valerio Giorgetta