A 1.8V 5-bit Segmented Current Steering Digital-to-Analog Converter

This paper presents the current steering Digital-to-Analog Converter (DAC). A segmented architecture has been implemented in this paper. A 5-bit DAC has been designed to convert the binary inputs to their equivalent analog current. The segmentation is done in such a way that the three most significant bits use binary-weighted current sources and the two least significant bits use unary-weighted current sources. The two least significant bits are converted to thermometric code as 2^N-1 current sources of unary weight are used. A cascoded current reference circuit is designed to bias the arrays of the current mirror circuit. A thermometric encoder is designed to code the two least significant bits of digital input to thermometer code. The DAC architecture using different types of switches is simulated and optimized to obtain better results. The maximum Integral Non-Linearity is 0.1498 LSB and the maximum Differential Non-Linearity is 0.1256 LSB.