12-bit SAR ADC with 8-channel multiplexer — 200k SPS throughput
The Texas Instruments ADC128S022CIMT/NOPB is a 12-bit successive-approximation-register (SAR) ADC with an integrated 8-channel multiplexer and sample-and-hold, sampling at 200k samples per second. The SAR architecture delivers a deterministic conversion time with no pipeline delay — every sample is ready one clock cycle after the start bit, making it predictable for real-time control loops. The 8 single-ended inputs let one ADC serve up to eight analog channels — think thermistor strings, potentiometer banks, or multi-sensor analog front-ends — without an external mux. The internal MUX-S/H-ADC configuration means the sample-and-hold capacitor shares the mux output, so channel-to-channel skew is limited to the mux settling time, not the ADC acquisition time.
Supply flexibility and interface — single-rail operation, SPI or DSP
No external reference IC is needed, which saves board area and BOM cost, but the ADC's accuracy tracks the supply tolerance: a 1 % supply ripple translates directly into a 1 % gain error. The data interface supports SPI or DSP-compatible framing — a 4-wire SPI bus (SCLK, CS, DOUT, DIN) or a 3-wire DSP mode where the chip select doubles as the frame sync.
The SAR architecture is inherently monotonic over temperature — no missing codes at the endpoints — so the resolution stays valid across the full range.
