Patent ID: 6820220
Filing Date: 2004-11-16
Classification: G05B

Abstract:
A control unit for controlling a safety-critical application, the control unit comprising:a microcomputer; a monitoring unit including a first arrangement for measuring a quiescent current of the microcomputer, and including a second arrangement for applying a test data input signal, for processing test data output signals and for comparing a corresponding test data output signal of the microcomputer to a corresponding test data output signal of the monitoring unit; at least one quiescent current handshake line running between the first arrangement and the microcomputer for controlling the measuring of the quiescent current; at least one test data signal transmission line running between the second arrangement and the microcomputer; and peripheral circuits; wherein: the first arrangement includes an IDDQ measuring circuit, a voltage supply, an IDDQ measuring run control, and a control system of the monitoring unit; the at least one quiescent current handshake line includes two handshake lines running from the IDDQ measuring run control to the microcomputer; the first arrangement and the microcomputer are coupled by the two handshake lines and at least one voltage supply line running from the voltage supply to the microcomputer; and at least one of the at least one voltage supply line runs through the IDDQ measuring circuit.