US 12,339,301 B2
AC/DC voltage detection circuit
Ning Zhu, Wuxi (CN)
Assigned to Hypower Microelectronics (Wuxi) Co., Ltd., Wuxi (CN)
Filed by Hypower Microelectronics (Wuxi) Co., Ltd., Wuxi (CN)
Filed on Oct. 13, 2023, as Appl. No. 18/380,151.
Application 18/380,151 is a continuation of application No. 17/467,464, filed on Sep. 7, 2021, granted, now 11,828,777.
Claims priority of application No. 202110690635 (CN), filed on Jun. 22, 2021.
Prior Publication US 2024/0103050 A1, Mar. 28, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. H03K 5/24 (2006.01); G01R 19/25 (2006.01)
CPC G01R 19/2509 (2013.01) [H03K 5/24 (2013.01)] 13 Claims
OG exemplary drawing
 
1. An alternating current (AC)/direct current (DC) voltage detection circuit, comprising:
a voltage divider circuit to generate an operation voltage from a high voltage;
a rising edge trigger circuit, including an input terminal and an output terminal, wherein
the rising edge trigger circuit samples the operation voltage received by the input terminal with a preset clock period,
the clock period is configured to enable the rising edge trigger circuit to sample M times to an AC voltage of a rated frequency at its rising edge, wherein M is a natural number, and
when an increase of the operating voltage at the rising edge of the operating voltage within the preset clock period is greater than a preset bias voltage, an output signal of the output terminal undergoes at least one target flip between a high level and a low level,
a detection and output circuit, connected to the output terminal of the rising edge trigger circuit, and configured to detect a change of the operating voltage and the target flip, wherein when the detection and output circuit detects that the output signal of the rising edge trigger circuit undergoes preset m target flips in M consecutive clock periods, the detection and output circuit generates an AC determination signal, when the detection and output circuit detects that the output signal of the output terminal undergoes less than m target flips at the rising edge of the operating voltage, the detection and output circuit generates a DC determination signal, where m is a natural number; and
a determination circuit to determine whether the operating voltage is higher than a preset voltage, wherein when the operating voltage is higher than the preset voltage, the determination circuit activates the detection and output circuit to detect the change of the operating voltage and the target flip.