12-bit SAR ADC for extended-temperature data acquisition
The Maxim Integrated MAX11666AUB/V+ is a 12-bit successive-approximation-register (SAR) ADC with a 2-channel multiplexer, single-ended inputs, and a 1:1 S/H-to-ADC ratio. It samples at 500 ksps over an SPI interface and operates from a single 2.2 V to 3.6 V supply for both analog and digital rails.
At 500 ksps the ADC can digitize a 250 kHz full-scale sine wave with adequate margin for Nyquist sampling. For multiplexed systems switching between the two single-ended inputs, the 1:1 S/H ratio means the acquisition time is shared across channels — budget 2 µs per conversion plus settling. The SAR architecture delivers no pipeline delay, so each sample corresponds to a single conversion result, which simplifies control loops in motor-drive or power-inverter current sensing.
Supply-rail flexibility and reference
The reference type is supply-based (VDD), so the full-scale range tracks the analog supply. For a 3.3 V rail the LSB is 806 µV; at 2.5 V it drops to 610 µV.
The 10-uMAX-EP (exposed pad) package measures 3.00 mm × 3.00 mm (0.118" width) and requires a thermal-land pattern on the PCB.
It is ROHS3 compliant. For volume or long-term programs, confirm lead time and allocate buffer stock through the RFQ process.
