US 11,888,310 B1
Methods and apparatus for precharge monitoring of high voltage circuits
Venkatesh Prasad Hanglur Narasimha, San Mateo, CA (US); and James Michael Castelaz, Alameda, CA (US)
Assigned to Motiv Power Systems, Inc., Foster City, CA (US)
Filed by Motiv Power Systems, Inc., Foster City, CA (US)
Filed on Aug. 25, 2021, as Appl. No. 17/412,017.
Claims priority of provisional application 63/069,959, filed on Aug. 25, 2020.
Int. Cl. H02H 9/00 (2006.01); H02H 9/04 (2006.01)
CPC H02H 9/001 (2013.01) [H02H 9/045 (2013.01)] 23 Claims
OG exemplary drawing
 
1. An apparatus comprising:
a precharge switch that selectively enables or disables precharge current from a Direct Current (DC) source to a capacitor;
a comparison circuit that generates a switch control signal to continuously control the precharge switch, wherein the switch control signal is generated based on a comparison between a scaled version of a circuit voltage and a reference voltage; and
a reference circuit that receives a precharge command signal and generates the reference voltage, wherein the precharge switch changes state in response to the precharge command signal changing state.