Current signal precision sampling module of transmitter for electrical exploration

A current signal precision sampling module of a transmitter for electrical exploration includes a DC/DC converter U2 and U3, an isolation amplifier U4, a program control amplifier U5 and a sampling resistor U6; a pin 1 and a pin 2 at the power input terminal of two DC/DC converters U2 and U3 are connected; a positive power output from a pin 6, a negative power output from a pin 4 and a power ground output from a pin 5 of the DC/DC converter U2 are respectively connected with pins 1, 2 and 28 of the isolation amplifier U4; the positive power output from the pin 6, the negative power output from the pin 4 and the power ground output from the pin 5 of the DC/DC converter U3 are respectively connected with pins 15, 16 and 14 of the isolation amplifier U4; the positive power output from the pin 6, the negative power output from the pin 4 and the power ground output from the pin 5 of the DC/DC converter U3 are respectively connected with pins 13, 8 and 4 of the isolation amplifier U5; the sampling resistor U6 is connected with pins 27 and 28 at the sampling signal input terminal of the isolation amplifier U4; and pins 13 and 14 at the signal output terminal of the isolation amplifier U4 are in signal connection with the pin 5 signal input terminal and the pin 4 of the program control amplifier U5. The utility model could simultaneously measure the heavy current and the small current in a precise way and has low power consumption.