Title: Multi-state semiconductor tachometer circuit

Abstract: A tachometer circuit in accordance with the invention has two or more output states dependent upon the frequency of an applied signal. The tachometer circuit is of the type comprising at least one time-measurement circuit having two discharge paths for a capacitor which forms part of a time-constant network. One of the discharge paths is controlled by the applied signal and the other path is caused to conduct after a predetermined time. In the circuit of the present invention the discharge path to which the input signal is applied includes a thyristor or like element with a high holding current which ensures a non-controllable discharge of the capacitor, and the other discharge path comprises a unijunction transistor or like element with a low holding current.

Do you think this is a good invention? Vote now:

Votes so far: For:(0) Against:(0)
Other info:

Inventors: Lombard, Claude (Le Chesnay, FR)

Application Number: 567204
Filing Date: 1975-04-11
Publication_date: 1976-12-07
Assignee: Regie Nationale des Usines Renault (FR)
Primary Class(es): 327/37 327/187, 327/261
Other Classes:
US Patent Ref:

3033994	May, 1962	Fujimoto et al.	307/228.
3372683	Mar, 1968	Phillips et al.	307/284.
3567969	Mar, 1971	Goode et al.	307/247.
3704382	Nov, 1972	Huntzinger	307/271.

Other Refs:
Primary Examiner: Heyman, John S.
Assistant Examiner:
Attorney: Beveridge, DeGrandi, Kline & Lunsford