Robust gauge driving circuit with pulse modulated input
摘要
An input circuit for an automotive gauge driver receives a pulse width modulated or pulse frequency signal having a duty cycle representing a parameter to be displayed. A switching transistor controls an RC filter to develop an analog voltage proportional to the parameter. The input circuit biases the transistor to correctly respond to the input signal over a large range of supply voltage and where the ground potential differs from that of the source of the input signal. An output transistor means (or two) in series with a gauge coil (or two) is controlled by the analog voltage to provide coil current to effect linear gauge operation. Diodes in the input circuit limit the analog voltage range to end values which match the turn-on characteristics of the transistor means.
申请公布号
US5698974(A)
申请公布日期
1997.12.16
申请号
US19950387991
申请日期
1995.02.13
申请人
DELCO ELECTRONICS CORPORATION
发明人
VAN DYKE, AARON ROGER;SHEPARD, JEFFREY LYNN;ATHERTON, FRANK J.;PHALEN, MICHAEL DENNIS;LIPPMANN, RAYMOND;MEJEUR, JAMES CARY;ROSS, DAVID ALAN