AD2S80AAD

Overview

The AD2S80AAD is a monolithic resolver-to-digital converter manufactured using BiMOS II technology, housed in a 40-lead DIP package. It provides user-selectable resolution of 10, 12, 14, or 16 bits via SC1 and SC2 pins. The device operates with ±12 V analog supplies and +5 V logic supply, supporting reference frequencies from 50 Hz to 20,000 Hz. Angular accuracy is specified at ±8 arc minutes for the A-grade variant. Maximum tracking rates vary by resolution: 1040 rps at 10-bit, 260 rps at 12-bit, 65 rps at 14-bit, and 16.25 rps at 16-bit. It features a parallel natural binary output, an analog velocity signal, and industrial temperature range operation (-40°C to +85°C).

Feature Summary

• User-selectable resolution (10, 12, 14, or 16 bits) controlled by SC1/SC2 logic inputs.
• Ratiometric tracking conversion providing high noise immunity and tolerance to lead length.
• Analog velocity output proportional to rotation speed, linear to typically one percent.
• Industrial temperature grade (-40°C to +85°C) with ESD Class 2 protection.

Applications

• DC Brushless and AC Motor Control
• Process Control Systems
• Numerical Control of Machine Tools
• Robotics Axis Control
• Military Servo Control

Procurement Notes

Verify the suffix 'AD' confirms the industrial temperature range (-40°C to +85°C). Confirm the package type matches the required 40-lead DIP configuration. Ensure power supply rails are within ±10% of nominal ±12 V for analog supplies and ±10% of +5 V for logic. Check datasheet for specific angular accuracy grades (A, B, J, K, etc.) if precision requirements exceed standard specifications.

Selection Notes

Select external components R4 and R6 based on the chosen resolution and desired maximum tracking rate. Ensure the ratio of reference frequency to closed-loop bandwidth adheres to guidelines (e.g., 7.5:1 for 16-bit resolution). Use preferred value resistors and capacitors with 5% tolerance. Connect SIN/COS signals using individually screened twisted pairs to minimize coupling between sine and cosine channels.

Part Context

The AD2S80A belongs to the AD2S8X series of variable resolution resolver-to-digital converters. It is designed to replace discrete solutions by integrating phase-sensitive detection, integration, and digital counting on a single chip. The AD2S80AAD specifically denotes the industrial temperature variant of this family, suitable for environments requiring wider thermal stability than commercial grades.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. The AD2S80AJD and AD2S80ABD are variants differing primarily in temperature range and accuracy grade rather than functional pinout or electrical performance.

FAQ

How is the resolution of the AD2S80AAD configured?

Resolution is set by the logic states of the SC1 and SC2 pins: 0/0 for 10-bit, 0/1 for 12-bit, 1/0 for 14-bit, and 1/1 for 16-bit.

What is the maximum tracking rate at 16-bit resolution?

At 16-bit resolution, the maximum tracking rate is 16.25 revolutions per second (rps).

Can the AD2S80AAD replace a tachogenerator?

Yes, the device provides an analog velocity output signal proportional to the rate of change of the input angle, which can be used in place of a conventional tachogenerator.