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1. An origin location detection circuit in an encoder, the encoder including a scale on which an origin pattern indicating an origin is provided and a detection head relatively displaceable with respect to the scale, the origin location detection circuit comprising:
a comparator configured to generate an origin signal indicating a location of the origin from an output voltage signal, which is output from a detector of the detection head and has been affected by the origin pattern; a DC voltage detection circuit comprising a low-pass filter, the low-pass filter comprising a resistor directly coupled to the detector, the resistor allowing the output voltage signal to pass, the DC voltage detection circuit configured to smooth the output voltage signal; and a differential amplifier circuit configured to perform differential amplification of the output voltage signal and a DC voltage signal output from the DC voltage detection circuit, wherein the comparator is further configured to receive a differential amplifier signal of the differential amplifier circuit.
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