Disclosed is a signal transmission circuit, comprising: a common interface, a first switch, a second switch, and an interference-resistant branch; the common interface is configured to, receive a digital signal through the first switch when the first switch is closed, or to receive an analog signal through the second switch when the second switch is closed; the interference-resistant branch is configured to eliminate an interference of the second switch on the digital signal; a signal input of the interference-resistant branch is configured to receive the digital signal, and a signal output of the interference-resistant branch is connected to a signal input of the first switch; and/or, the signal input of the interference-resistant branch is connected to a signal output of the second switch, and the signal output of the interference-resistant branch is connected to a signal input of the common interface.