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. The part is packaged in a 10-uMAX-EP (exposed pad) and rated for -40°C to +125°C, making it suitable for industrial and automotive sensor interfaces, motor-control feedback, and battery-monitoring systems where wide temperature range and moderate throughput are required.
500 ksps throughput — what it means for the signal chain
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. This eliminates the need for a separate reference IC, but it also ties ADC accuracy to the regulation of the supply — a low-noise LDO on the analog rail is recommended if the digital supply carries switching ripple.
Package and thermal management
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. The exposed pad must be soldered to a ground plane with thermal vias to keep junction temperature within limits, especially when operating at 125°C ambient and 500 ksps continuous conversion. The tube shipping medium is typical for prototype and small-run quantities; reel options for production volume are available through the supply chain.
Lifecycle and compliance
It is ROHS3 compliant. No official successor or pin-compatible second source is listed in the available records, so the part is single-sourced from Maxim Integrated (now part of Analog Devices). For volume or long-term programs, confirm lead time and allocate buffer stock through the RFQ process.