Precision DACs include general purpose (General Purpose) and bipolar (Bipolar), which are divided according to the VREF input range and bandwidth. Generally speaking, general purpose DACs use a resistor string (R-String) structure. Across the positive and negative power supplies, usually in a narrow range, such as about 2.5V, and the bandwidth is narrow, generally below 1MHz; the VREF range of the bipolar DAC spans the positive and negative power supplies, including ground level; the bandwidth of VREF is wide , It can even reach 10MHz under some codewords, and the amplitude can reach ±18V. We are used to calling this type of bipolar DAC a multiplier type (Multiplying) DAC or MDAC. Because of its flexible use, simple operation, and excellent precision, MDAC is widely used in the industry, and multiplier-type DACs often appear in college students' electronic design competitions.
