Texas Instruments Corporation

David H Elwart, Ii

Baher S Haroun

Rakesh Raja

Anuj Jain

Christopher Michael Graves

Sudhir Nagaraj

Vikas Suma Vinay

A system and method for a decay lock loop for time varying current regulation in electric motors determines if a predetermined electrical current regulation level for an electric motor has been obtained within a tuning control time window. A coarse control loop increases or decreases a fast current decay, in response to a determination that the predetermined electrical current regulation level has not been obtained within the tuning control time window, until the predetermined electrical current regulation level falls within the tuning control time window. A fine control loop increments or decrements an amount of fast current decay during a total decay time, in response to a determination that the predetermined electrical current regulation level has been obtained within the tuning control time window, until a predetermined timing of the predetermined electrical current regulation level has been obtained.

Decay lock loop for time varying current regulation in electric motors

Self-grounded circuitry () includes a signal channel conducting an output voltage (V). A charge pump () powered by a reference voltage (V) produces a control voltage (V). The control signal is at a low level if the reference voltage is low and is boosted to a high level if the reference voltage is high. A ground switch circuit () includes a depletion mode transistor (MP) having a source coupled to the output voltage, a gate coupled to the control voltage, and a drain coupled to ground. The transistor includes a well region (-) and a parasitic substrate diode (D-). A negative voltage protection circuit (-) includes a depletion mode first protection transistor (MP-) having a drain coupled to the well region, a source coupled to a source of a depletion mode second protection transistor (MP-) having a drain coupled to the output voltage, the first and second protection transistors each having a gate coupled to the control voltage, and also includes a diode (MN) coupled to charge the well region from the control voltage conductor to prevent distortion of the output voltage.

Negative audio signal voltage protection circuit and method for audio ground circuits

Growing community of inventors

Sachse, TX, United States of America

David H Elwart, Ii