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The transient electromagnetic method (TEM) is an effective tool for investigating the subsurface resistivity structure. An important requirement for accurate investigation of the shallow depth is a transmitter current with the steep and linear falling-edge. We present a scheme for fast turning off the bipolar pulse current of low-power TEM transmitter. The scheme exploits the passive voltage-clamp circuit and the divided transmitter loop. The moment the current is switched off, the transmitter loop is divided into two equal parts. Synchronously, the inverse constant high voltage is added to each loop parts by the voltage-clamp circuit. We evaluate the effect of proposed scheme by using the equations of fall time and linearity. Simulation and experimental results show that the transmitter current has a short fall time and a highly linear falling-edge, which is especially useful for mine or shallow TEM surveys.