8-bit SAR ADC with MUX — 50k SPS throughput for multiplexed signals
The MAX1112EAP+ is an 8-bit SAR ADC from Analog Devices, sampling at 50k samples per second through an internal multiplexer that accepts either 4 differential or 8 single-ended inputs. The MUX-S/H-ADC architecture means the single converter is shared across all channels, so the per-channel throughput drops as you enable more inputs — at 8 single-ended channels, each sees roughly 6.25k SPS. Both analog and digital supply rails are 5V, eliminating the need for a separate I/O voltage rail when interfacing with a 5V-tolerant SPI bus. The SPI data interface keeps the pin count low and the layout simple — four wires (SCLK, DIN, DOUT, CS) handle all communication.
Package and board-fit — 20-SSOP with 0.209-inch body width
The 20-SSOP footprint is common and well-supported by standard land patterns — no exotic pad geometry required. The 1:1 S/H-to-ADC ratio means the sample-and-hold capacitor is dedicated to the active channel, so there is no charge-sharing penalty when switching between inputs — the acquisition time is consistent regardless of which MUX channel is selected.