Current detection circuit for large current

The utility model belongs to the field of integrated circuit design and motor driving chips, and particularly relates to a current detection circuit for large current. The circuit is composed of a bias circuit, a low common mode input amplifier circuit, a current mirror circuit and an H-bridge circuit. Wherein the first PMOS tube M1, the second PMOS tube M2, the third PMOS tube M3, the fourth PMOS tube M4, the fifth PMOS tube M6, the fourth PMOS tube M5 and the eighth PMOS tube M9 are 5V PMOS tubes; the first NMOS tube M5 and the second NMOS tube M10 are NMOS tubes of 5V; a third NMOS (N-channel Metal Oxide Semiconductor) tube M11 and a fourth NMOS tube M12 are 40V NMOS tubes; the voltage VM of a power supply electrode in the internal circuit of the H bridge is 40V, the inductor L1 is an adjustable inductor, and the fifth NMOS tube M13, the sixth NMOS tube M14, the seventh NMOS tube M15 and the eighth NMOS tube M16 are 40V withstand voltage NMOS tubes. According to the design, after the voltage withstanding c