# Digital to Analog converter [[Digital-Analog Interfaces]] ## DACs we know something about - [[AD9744]] - [[AD9208]] - [[Analog Devices DAC selection table]] ## Types of DAC ### Binary Weighted Resistor - Multiple values of resistors - Each bit corresponds to the current flow through one resistor - Somewhat high thermal dissipation - more bits means much high value resistors - High value resistors are more prone to error ![[Pasted image 20221106003516.png]] ### [[R-2R Ladder Circuit DAC]] ### [[PWM]] DAC This is probably the most common DAC method because you get it for free with most digital microcontrollers. [[Sigma Delta DAC]] ## Linearity Measured in [[LSB]], Least Significant Bit Linearity of 1 -> Within one LSB of the actual value ex: 8 bits -> 1111111==1== = 2^8 = 256 LSB = 0000000==1== = 1 Precision = 1/256 ## Monotonic https://www.planetanalog.com/dac-non-linearity-non-monotonicity-and-midpoint-glitches/ Going from one step to the next step - if it off by +1 LSB, then by -1 LSB, the output will dip even though the input has been increasing. ![[monotonic.jpg|lg]] ## Settling Time https://www.planetanalog.com/dac-basics-part-1-finding-a-home-for-your-dac/ ![[Screenshot 2023-03-18 at 4.05.39 PM.jpg]]