US 12,288,981 B2
Surge protection circuit
Chih-Yun Lin, New Taipei (TW); and Chih-Hsing Chen, New Taipei (TW)
Assigned to POWERTECH INDUSTRIAL CO., LTD., New Taipei (TW)
Filed by POWERTECH INDUSTRIAL CO., LTD., New Taipei (TW)
Filed on Jan. 29, 2023, as Appl. No. 18/161,081.
Claims priority of application No. 111208140 (TW), filed on Jul. 29, 2022.
Prior Publication US 2024/0039396 A1, Feb. 1, 2024
Int. Cl. H02H 9/04 (2006.01); H02H 9/00 (2006.01); H02M 7/06 (2006.01)
CPC H02H 9/04 (2013.01) [H02H 9/005 (2013.01); H02M 7/062 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A surge protection circuit, comprising:
a first stage filter circuit connected to an alternating current (AC) source, and configured to filter an AC input signal provided by the AC source to output an initial filtered signal;
a surge detection driver circuit connected to the first stage filter circuit, configured to detect the initial filtered signal, and configured to output a detection driving signal when the surge detection driver circuit determines that the initial filtered signal has a surge wave;
a surge suppressor circuit, including:
a plurality of snubber circuits, including:
a first snubber circuit connected to the AC source, and configured to attenuate the AC input signal from the AC source to output a first snubber signal; and
a second snubber circuit configured to attenuate a first filtered signal to output a second snubber signal; and
a plurality of power switches, including:
a first power switch, wherein a first terminal of the first power switch is connected to the first snubber circuit, a control terminal of the first power switch is connected to the surge detection driver circuit, and the first power switch operates to output a first surge suppressed signal according to the detection driving signal and the first snubber signal; and
a second power switch, wherein a first terminal of the second power switch is connected to the second snubber circuit, a second terminal of the second power switch is connected to an output terminal of the surge protecting circuit, a control terminal of the second power switch is connected to the surge detection driver circuit, and the second power switch operates to output a second surge suppressed signal as an AC output signal of the surge protecting circuit according to the detection driving signal and the second snubber signal; and
a multi-stage filter circuit connected to a second terminal of the first power switch and the second snubber circuit, and configured to filter the first surge suppressed signal from the second terminal of the first power switch to output the first filtered signal to the second snubber circuit.