Electricity: measuring and testing – Electrolyte properties
Patent
2000-03-14
2000-12-26
Wong, Peter S.
Electricity: measuring and testing
Electrolyte properties
324432, G01N 2742
Patent
active
061665479
ABSTRACT:
A line card circuit to prevent false off-hook signals resulting from the permanent loss of battery voltage at a line card. In the battery present condition, the 5V operating voltage is connected to the collector lead of an NPN transistor, which also supplies the output signal of the system. The emitter lead of the transistor is connected to ground. The -48V battery voltage is connected to the transistor base lead and biases the base negative with respect to the emitter, maintaining the 5V logic "1" output signal on the collector lead. There is a resistor and capacitor in series, forming an RC circuit, across the 5V collector lead and the -48V base lead. In the battery present condition, there is a significant charge across the capacitor. In the battery absent condition, the -48V battery voltage is lost and the voltage on the base lead rises to a positive voltage in a time interval governed by the discharge time of the RC circuit, thus causing the system output signal to drop to logic "0".
REFERENCES:
patent: 5214369 (1993-05-01), McCrea
patent: 5444777 (1995-08-01), Condon et al.
patent: 5684384 (1997-11-01), Barkat et al.
patent: 5933010 (1999-08-01), Moreno
De La Rosa Cesar Covarrubias
Sciabica Frank
AG Communication Systems Corporation
Luk Lawrence
Wong Peter S.
Zwick David J.
LandOfFree
Line card loss of battery detector does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Line card loss of battery detector, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Line card loss of battery detector will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-998906