In order to enhance the security and reliability of the signal transmission in the harsh electrical noisy environment, an isolated communication chip was proposed and designed to realize the remote control of the equipment by SPI data link. The advantages and disadvantages of two current SPI isolation schemes were analyzed. Considering the isolation method, circuit complexity, cost, reliability, and other factors, the chip uses the “balanced” two-wire technology and encodes the four SPI signals into DC-free pulse that can be coupled by a transformer, which can improve the accuracy of data transmission and system reliability. The chip was designed and fabricated in GSMC 0.18 μm CMOS standard process, with a total chip area of 1.33×1.45 mm2. Test results show that the chip can reach a bit error ratio of 10-9 at 1 Mbps. The maximum cable length supported at a data rate of 0.5 Mbps can be up to 50 meters. It achieves the flexible network configuration of the remote controlled device. Compared with other similar isolation schemes, the designed chip is a low-cost, highly reliable and structural optimization solution for remote control.