Add plots

README.md

@@ -36,6 +36,10 @@ At a build quantity of 10, BOM cost is around $3.00 + $0.67 n, where n is the
 number of output channels up to 8. This gets you a full 15 bits! Also, most
 parts are quite generic and can be easily substituted if hit by part shortages.
 
+Here, have some plots:
+
+![Plot of DNL and INL vs DAC code](doc/2022-12-26_18.51.48-inldnl.png)
+
 ## Why you shouldn't use it
 
 The design has some drawbacks, as does any DAC. Here are some reasons TIMDAC