US 12,438,538 B2
Motor driver circuit
Suzunosuke Kimura, Kyoto (JP); Kosuke Yasuji, Kyoto (JP); and Hiroki Sugamoto, Kyoto (JP)
Assigned to ROHM CO., LTD., Kyoto-shoi (JP)
Filed by ROHM CO., LTD., Kyoto (JP)
Filed on Mar. 26, 2024, as Appl. No. 18/616,703.
Claims priority of application No. 2023-052366 (JP), filed on Mar. 28, 2023.
Prior Publication US 2024/0333280 A1, Oct. 3, 2024
Int. Cl. H03K 17/30 (2006.01); H02M 3/07 (2006.01); H03K 17/041 (2006.01)
CPC H03K 17/302 (2013.01) [H02M 3/07 (2013.01); H03K 17/04106 (2013.01); H03K 2217/0063 (2013.01); H03K 2217/0072 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A motor driver circuit, comprising:
a logic circuit, configured to generate a control signal that instructs a high-side transistor to turn on or off; and
a high-side driver, configured to drive the high-side transistor according to the control signal, wherein
the high-side driver includes:
a voltage monitoring circuit, configured to
compare a detection voltage with a threshold value, wherein the detection voltage is a gate voltage or a gate-source voltage of the high-side transistor, and
assert a detection signal when the detection voltage becomes lower than the threshold value;
a timer circuit, configured to start measuring a predetermined time in response to the control signal changing to an on state that the high side transistor is instructed to turn on, or in response to assertion of the detection signal when the control signal is in the on state;
a charge pump circuit, configured to
be active when the timer circuit measures the predetermined time,
generate a boosted voltage in response to a clock signal, and
supply the boosted voltage to a gate of the high-side transistor; and
a turn-off circuit, configured to reduce a voltage at the gate of the high-side transistor when the control signal instructs the high-side transistor to turn off.