US 11,705,922 B2
Apparatus and system for a programmable resistance circuit
Kenneth T. Myers, Clarkston, MI (US)
Assigned to Joyson Safety Systems Acquisition LLC, Auburn Hills, MI (US)
Filed by Joyson Safety Systems Acquisition LLC, Auburn Hills, MI (US)
Filed on Jun. 3, 2021, as Appl. No. 17/338,635.
Claims priority of provisional application 63/034,362, filed on Jun. 3, 2020.
Prior Publication US 2021/0384915 A1, Dec. 9, 2021
Int. Cl. H03M 1/78 (2006.01); B60K 35/00 (2006.01); H03K 5/08 (2006.01); H03K 17/74 (2006.01)
CPC H03M 1/785 (2013.01) [B60K 35/00 (2013.01); H03K 5/08 (2013.01); H03K 17/74 (2013.01); H03M 1/78 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A programmable resistance circuit for configuring a reference resistor to exhibit a plurality of resistance values and providing a respective resistance value from a source connection relative to a return circuit connecting a return signal to at least one external electronic control module, the programmable resistance circuit comprising:
a transistor configured for connecting to the reference resistor, the transistor being connected to an analog return line from the programmable resistance circuit;
a modulated voltage source connected to a local ground and the transistor, wherein the modulated voltage source biases the transistor between a first state allowing forward current flow to the analog return line and a second state exhibiting a high impedance to the forward current flow to the analog return line,
wherein the first state and the second state respectively emulate turning the reference resistor off and on to establish the average respective resistance value to the at least one external electronic control module and to establish an average output voltage across the programmable resistance circuit;
wherein the analog return line connects to a remote ground of the at least one external electronic circuit module such that the analog return line is isolated from the local ground of the programmable resistance circuit.