AD7849ANZ

Overview

The AD7849ANZ is a 14-bit/16-bit serial input multiplying digital-to-analog converter (DAC) manufactured by Analog Devices. It features a resistor string architecture ensuring monotonicity to 14 bits for the A grade and 16 bits for other grades. The device operates with analog supplies of ±14.25 V to ±15.75 V and a digital supply of 4.75 V to 5.25 V. Key electrical parameters include a settling time of 7 μs to 0.006% FSR, a maximum power dissipation of 100 mW, and an external reference requirement. It is housed in a 20-lead PDIP package.

Feature Summary

• Guaranteed monotonicity: 14 bits for A grade, 16 bits for B/C grades over temperature.
• Versatile serial interface supporting standalone and daisy-chain modes via SDIN/SCLK/SDOUT.
• Output clamped to 0 V during power-up/down sequences via internal voltage monitor.
• Configurable output coding via BIN/COMP pin for binary or two's complement formats.

Applications

• Industrial process controls
• PC analog I/O boards
• Instrumentation systems

Procurement Notes

Verify the specific grade suffix (A, B, or C) as resolution and accuracy specifications vary between 14-bit and 16-bit performance. Confirm the package type matches the design requirements, as the AD7849 series includes both SOIC and PDIP options. Ensure power supply rails meet the specified ranges for proper operation of the multiplying DAC architecture.

Selection Notes

Select the AD7849ANZ when a 14-bit resolution is sufficient, as this grade offers tighter linearity specifications compared to higher grades at lower costs. Consider the external reference requirement and the need for bipolar or unipolar output configurations. Evaluate the serial interface compatibility with the host microprocessor, noting the support for daisy-chaining multiple devices.

Part Context

The AD7849 belongs to the AD7849 family of serial input DACs from Analog Devices. This family includes variants such as AD7849AR, AD7849BRZ, and AD7849CRZ, which differ primarily in resolution grades (14-bit vs. 16-bit), packaging (SOIC vs. PDIP), and shipping formats. The ANZ designation specifically indicates the A-grade version in a 20-lead PDIP package.

Replacement Considerations

Direct replacements within the same family include AD7849BNZ (16-bit, PDIP) and AD7849CNZ (16-bit, PDIP). For PCB footprint compatibility, ensure the replacement maintains the 20-lead PDIP outline dimensions. Note that switching grades may alter linearity and accuracy specifications.