US 12,278,476 B2
Under voltage protection circuit and device
Wenqing Wang, Shenzhen (CN); and Jing Liu, Shenzhen (CN)
Assigned to BYD SEMICONDUCTOR COMPANY LIMITED, Shenzhen (CN)
Filed by BYD SEMICONDUCTOR COMPANY LIMITED, Shenzhen (CN)
Filed on Dec. 22, 2022, as Appl. No. 18/145,216.
Application 18/145,216 is a continuation of application No. PCT/CN2021/102906, filed on Jun. 29, 2021.
Claims priority of application No. 202010610382.5 (CN), filed on Jun. 30, 2020.
Prior Publication US 2023/0117084 A1, Apr. 20, 2023
Int. Cl. H02H 3/24 (2006.01); H02H 1/00 (2006.01)
CPC H02H 3/24 (2013.01) [H02H 1/0007 (2013.01)] 10 Claims
OG exemplary drawing
 
1. An under voltage protection circuit, comprising:
a primary-side input module, and a secondary-side output module,
wherein the primary-side input module is connected with the secondary-side output module, and the secondary-side output module comprises:
an under voltage determination unit, configured to compare a voltage of the secondary-side output module with a preset voltage, wherein a first control signal is outputted when the voltage of the secondary-side output module is greater than or equal to the preset voltage; and a second control signal is outputted when the voltage of the secondary-side output module is less than a preset voltage;
a pulse signal generation unit, configured to transmit a periodic first pulse signal according to the first control signal and transmit a second pulse signal according to the second control signal, wherein a pulse width of the second pulse signal is greater than a pulse width of the first pulse signal,
wherein:
the under voltage determination unit is connected with the pulse signal generation unit; and
the primary-side input module is configured to determine, according to the first pulse signal, that the secondary-side output module is in a non-under voltage state and determine, according to the second pulse signal, that the secondary-side output module is in an under voltage protection state.