12-bit SAR ADC in a SOT-23-8 — what the specs mean for your board
The Maxim MAX1286EKA+T is a 12-bit successive-approximation-register (SAR) analog-to-digital converter with a single-ended input configuration, two input channels, and a 1:1 sample-and-hold to ADC ratio. It samples at 150k samples per second over the SPI bus, making it a compact choice for embedded data acquisition where board area is tight. The 5V analog and digital supply rails are shared — both run on the same 5V rail, so there is no separate AVDD/DVDD split to manage. The SOT-23-8 package (also listed as Supplier Device Package SOT-23-8) keeps the footprint small. Operating temperature spans -40°C to 85°C, the industrial grade.
150k samples per second — where it fits and where it doesn't
At 150k samples per second, this ADC handles slow-to-moderate signals: temperature, pressure, current sense, potentiometer feedback, and general-purpose analog monitoring. It will not capture audio bandwidth or fast transient events — those need a higher sample rate or a pipelined architecture. The SAR architecture gives cycle-by-cycle conversion with no pipeline delay, so each sample is a fresh measurement. That matters for multiplexed inputs where you need a settled reading per channel without waiting for a pipeline flush. The SPI data interface runs at whatever clock rate the master provides, up to the ADC's maximum. No parallel bus, no extra I/O pins — just three or four wires (SCLK, DIN, DOUT, /CS) to the microcontroller.
Supply and reference — the 5V constraint
Both analog and digital supplies are 5V. The digital supply powers the SPI interface logic, so the SPI output levels are 5V CMOS. The reference is external (Reference Type: External), so the full-scale range is set by the voltage applied to the REF pin.
Lifecycle and sourcing
The MAX1286EKA+T carries an Active product status and is ROHS3 compliant. For a BOM line, this is a low-risk fit for both prototype builds and production runs.