AD7667ASTZ vs AD7663ASTZ

Both are 16-bit, 1 MSPS successive-approximation ADCs from Analog Devices in a 48-lead LQFP package, but they differ in input architecture and interface. The AD7663ASTZ provides a differential input with a flexible parallel or serial interface, while the AD7667ASTZ offers a unipolar single-ended input with a parallel interface. The AD7667ASTZ also integrates an internal reference buffer configuration optimized for single-ended signal chains, whereas the AD7663ASTZ is designed for differential signal acquisition.

Both devices are offered in the same 48-lead LQFP (STZ) package, but pin compatibility must be confirmed against the respective Analog Devices datasheets. The analog input pins and reference pins differ in function between the differential AD7663ASTZ and the single-ended AD7667ASTZ, so a direct drop-in replacement on an existing PCB is not guaranteed without verifying the pin functions and external component connections.

Yes. Both the AD7663ASTZ and AD7667ASTZ are specified as 16-bit successive-approximation ADCs with a maximum throughput of 1 MSPS, per Analog Devices datasheets. Both achieve their full 16-bit no-missing-code performance at that rate, making them suitable for high-resolution data acquisition in instrumentation, medical, and industrial systems.

The AD7663ASTZ supports a fully differential analog input, which is beneficial for rejecting common-mode noise and improving dynamic performance in differential signal chains. The AD7667ASTZ supports a single-ended unipolar input, simplifying interface to single-ended sensors and signal conditioning. The choice between them depends on whether the application requires differential or single-ended signal acquisition.

The AD7663ASTZ provides both a parallel interface and a serial interface, giving flexibility in connecting to microcontrollers, DSPs, or FPGAs. The AD7667ASTZ provides a parallel interface for host connection. Designers should confirm the specific interface mode and timing requirements in the respective Analog Devices datasheets before finalizing the digital interface design.

Both devices operate from a 5 V analog supply with a separate digital supply (typically 2.7 V to 5.25 V) for the interface, per Analog Devices documentation. Because the analog input architecture differs, the reference and input amplifier requirements differ, so the surrounding analog circuitry should be reviewed against each datasheet rather than assuming identical supply and reference configurations.

The AD7663ASTZ is the appropriate choice for differential sensor applications because its analog input is fully differential, allowing direct connection to differential signal sources and improved common-mode rejection. The AD7667ASTZ, with its single-ended input, is better suited to single-ended sensors or where a differential-to-single-ended conversion stage already exists in the signal chain.

Analog Devices provides evaluation boards and reference documentation for its 16-bit SAR ADC families, and designers should consult the official Analog Devices product pages for the AD7663 and AD7667 to confirm the specific evaluation board part numbers and available reference designs. Verified evaluation hardware and layout guidance should be obtained directly from Analog Devices or authorized distributors such as DigiKey or Mouser.