摘要:
An input circuit (30) for an I/O module (14e) for an industrial controller or the like provides a shunt regulator (38) for precisely controlling the maximum current through the LED (42) of an optical isolator (44). Substantial improvement in the current regulation decreases power dissipation in the optical isolator element. A low voltage shunt circuit (70) prevents leakage from the shunt regulator from activating the optical isolator at low voltages allowing more sensitive optical isolators providing additional power dissipation savings.
摘要:
Embodiments of the present invention disclose a digital signal input circuit. The circuit includes an isolating circuit and a voltage determining circuit, where a first port of an input end of the isolating circuit is connected to an input end of a digital signal, an output end of the isolating circuit is connected to an output end of the digital signal, and when the isolating circuit is open, the isolating circuit is configured to output a first level, or when the isolating circuit is closed, the isolating circuit is configured to output a second level; and an input end of the voltage determining circuit is connected to the input end of the digital signal, an output end of the voltage determining circuit is connected to a second port of the input end of the isolating circuit, and the voltage determining circuit is configured to determine, according to a level of the digital signal, whether the isolating circuit is open or closed. According to the digital signal input circuit, the voltage determining circuit determines a level of a digital signal, so as to avoid determining of a level of a digital signal by means of a light emitting diode in the prior art. In this way, correctness of digital signal level conversion is increased.
摘要:
Controlling power switches with a programmable gate controller system proximate associated power switches and remote from the central controller including sensing at least one predetermined condition local to the associated power switches; reporting the sensed conditions to the remote programmable gate controller system; developing, in response to the sensed condition at least one control signal in the remote programmable gate controller system; and applying the control signal to the associated power switches.
摘要:
Disclosed herein is a semiconductor integrated circuit capable of detecting an abnormality that can cause a malfunction in signal transmission via an isolation element and of issuing a stop signal to the target to be controlled. The semiconductor integrated circuit includes a transmission circuit generating and outputting a transmission signal reflecting transmission data supplied from outside, a reception circuit reproducing the transmission data based on a reception signal, an isolation element isolating the transmission circuit from the reception circuit and transmitting the transmission signal as the reception signal, an abnormality detection part detecting an abnormality that can cause a malfunction in signal transmission via the isolation element, and a control part outputting a stop signal if the abnormality detection part detects the abnormality, regardless of the transmission data supplied to the transmission circuit from outside.
摘要:
Eine Schaltung (10) zum Ein- und/oder Ausschalten eines elektrischen Verbrauchers (20) umfasst: ein elektrisch leitfähiges Bedienelement (11,), ein elektrisch betriebenes Leuchtmittel (12), das zwischen das Bedienelement und einen spannungsführenden Pol (L1) einer Wechselspannungsquelle derart eingeschleift ist, dass bei einer Betätigung des Bedienelements ein Strom durch das Leuchtmittel fließt, worauf das Leuchtmittel Licht emittiert, einen opto-elektrischen Wandler (13), der mit dem Leuchtmittel optisch gekoppelt ist, vor Umgebungslicht abgeschirmt ist und Licht, welches durch das Leuchtmittel emittiert wird, in elektrische Energie umwandelt, und ein Schaltmittel (14), das mit dem opto-elektrischen Wandler elektrisch gekoppelt ist und den elektrischen Verbraucher mit einer Versorgungsspannung (UV) verbindet oder von dieser trennt, wobei das Schaltmittel den elektrischen Verbraucher mit der Versorgungsspannung verbindet, wenn es durch den opto-elektrischen Wandler mit elektrischer Energie versorgt ist.
摘要:
A circuit for protecting an electronic device from excessive voltages applied to an input or output terminal (14) includes a solid state relay (120) coupling the electronic device to the terminal (14). The solid state relay (120) may include an optotransistor (130) coupled between the electronic device and the terminal (14) and a light emitting diode (124) optically coupled to the opto-transistor (130). The solid state relay (120) is coupled in series with a current limiting device (18,24), such as one or more enhancement mode field effect transistors. A voltage detector (30) coupled to the terminal detects a voltage larger than a specific value and causes current to flow thorough the light emitting diode (124), thereby interrupting the coupling between the terminal (14) and the electronic device. The voltage detector (30) may be coupled between two spaced-apart connections to the coupling path between the terminal to the electronic device so that the voltage detector avoids diverting current from the coupling path.