Achieving the best linearity and DC specifications requires a precision reference. The LTC275x DAC can accept a reference voltage between ±15V. Analog Devices offers the choice of many different references that match up with the LTC275x, depending on the need for accuracy, low temperature drift, or low noise. Table 6 from the LTC2757’s datasheet lists five different base part numbers. The dash option at the end of the part number represents the reference output voltage. The 5V LTC6655-5 is an ultra-stable voltage reference with an unequaled noise level of only 625nVp-p (0.25ppmp-p) from 0.1Hz to 10Hz.