Disclosed are a novel anti-lightning and over-voltage protection circuit and a protection apparatus. The protection circuit comprises a first piezo-resistor, a second piezo-resistor, a transient voltage suppressor diode, a positive temperature coefficient thermistor, a gas discharge tube and lead-out terminals, wherein the first piezo-resistor is in a series connection with the gas discharge tube, and the positive temperature coefficient thermistor is in a series connection with the transient voltage suppressor diode; and the two serial branches are connected in parallel, and then are connected to the second piezo-resistor in series to form a single-port combination circuit, wherein the performance of electric surge impact tolerance of the first piezo-resistor and the gas discharge tube is higher than the performance of electric surge impact tolerance of the second piezo-resistor; at least one of the two lead-out terminals of the single-port combination circuit is a low-thermal-resistance heat conduction terminal, and the positive temperature coefficient thermistor and/or the second piezo-resistor are/is respectively thermally coupled to the low-thermal-resistance heat conduction terminal; and the transient voltage suppressor diode can be replaced by a Zener diode or a voltage switch-type element.
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