Research and design of a high-precision analog multiplier

Bandwidth, power consumption and accuracy are the three main indicators for measuring the performance of analog multipliers. At present, the accuracy of low-power and high-bandwidth analog multipliers which are implemented by floating gate transistors and other methods is only about 1%, but the precision of the traditional Gilbert cell design can reach 0.5%. Therefore, in order to solve the problem of low precision of analog multiplier, a high-precision analog multiplier is designed by using the Gilbert unit. Firstly, the inverse hyperbolic tangent function circuit is used to compensate for the nonlinearity of the Gilbert unit to improve the system precision. Secondly, the linear transconductance structure is used to increase the input range of the circuit, so that it can be widely used. Then, a two-stage operational amplifier connected by negative feedback is designed to improve the load capacity of the system, using the negative feedback structure, not only the Z terminal can be introduced for addition, but also the precision and stability of the system can be improved. Finally, a current reference circuit with better thermal stability is designed to provide appropriate bias for each module. According to Cadence simulation verification, the working voltage of the circuit in this article is ±15 V, the input range of each terminal is -9 V to 9V, the precision can reach 0.08%, and the -3 dB bandwidth can reach 14.99 MHz. In addition, compared with several other classic circuits, the proposed circuit has better performance advantages because of the higher precision, lower power consumption, wider input range, and improved -3 dB bandwidth.