PCF8591 I²C ADC + DAC Lab

Add four analog inputs and one analog output to any MCU over a two-wire bus with one tiny NXP chip.

Difficulty: Through-hole. Estimated build time: about 35 minutes. Estimated parts cost: about US$4.00. 5-part bill of materials with live supplier pricing. An I²C analog-conversion peripheral built from the NXP PCF8591, an 8-bit chip that gives any MCU four single-ended ADC inputs and one DAC output in a single SOIC-16 package.