The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 24, 2001
Filed:
Mar. 01, 2000
Mathew Arthur Nieberger, Rocklin, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
An apparatus for controlling the illumination of two diode indicator lights with a single control line. The apparatus includes a circuit adapted to selectively provide one of high, low and medium voltage levels on a control output line responsive to combinations of high and low DATA and ENABLE signals. A first indicator is provided having a first diode with an anode and a cathode, the cathode being operatively connected to ground. A second indicator is provided having a second diode with an anode and a cathode, the cathode being operatively connected to a source of medium level voltage. A current limiting resistor is provided having a first end operatively connected to the anode of each of the first and second diodes, the opposite end thereof being connected to the control output line. Moreover, a pull-up resistor is provided having one end connected to the control output line and an opposite end connected to the medium level voltage source. The first diode indicator is switched on when the output line voltage level is medium, both of the first and second diode indicators are switched on when the voltage level is high and neither of the diode indicators are switched on when the voltage level is low.