ADC Selection for Potentiometers
Recommendation: MCP3208
For potentiometer inputs in a 3.3-5 V MIDI controller, the Microchip MCP3208 is the preferred ADC.
Requirements
- 16 analog inputs total
- ≥10-bit resolution
- 3.3 V operation
- Good availability from major distributors and LCSC
- Widely used / unlikely to become difficult to source
- Simple interface and easy firmware implementation
- Good Arduino, ESP and general hobbyist support
- Suitable for an open/hackable hardware platform
Candidates Evaluated
| ADC | Channels | Resolution | Interface | Assessment |
|---|---|---|---|---|
| MCP3208 | 8 | 12-bit | SPI | Best overall |
| ADC128S102 | 8 | 12-bit | SPI | Strong alternative |
| ADS7953 | 16 | 12-bit | SPI | More complex than necessary |
| MCP3008 | 8 | 10-bit | SPI | Excellent ecosystem, but lower resolution |
MCP3208 — Recommended
Two MCP3208s provide the required 16 inputs.
Key advantages:
- 12-bit resolution (4096 levels)
- Simple SPI protocol
- Operates from 2.7–5.5 V
- External VREF works particularly well for ratiometric potentiometer measurement
- Very widely available
- Long-established and popular part
- Multiple Arduino libraries and implementations
- Good ESP32/ESP8266 support
- Large amount of community knowledge and troubleshooting information
- Straightforward enough to drive directly without a library
- Available in convenient SOIC-16 packages
Its combination of availability, simplicity, resolution, community adoption and hackability makes it the strongest choice.