AEAS-7000 Datasheet, PDF (1/8 Pages) Agilent(Hewlett-Packard) – Plug and Play Ultra-Precision Absolute Encoder 16-bit Gray Code

AEAS-7000
Ultra-precision 16 bit Gray Code
Absolute Encoder Module
Data Sheet
Description
The encoder IC consists of 13 signal photo diode
channels and 1 monitor photo diode channel and is
used for the optical reading of rotary carriers (i.e., discs).
The photodiodes are accompanied with precision
amplifiers plus additional circuitry.
The monitor channel is used to drive a constant current
source for the highly collimated IR illumination system.
Functional Description
Background
The 13 signal channels are set up as:
1. Two precision defining signals (A0, A09), which are
two 90° electrical shifted sine, cosine signals. These
signals are conditioned to be compensated for offset
and gain errors. After conditioning they are on chip
interpolated
2. 11 analog (A1-A11) channels which are directly
digitized by precision comparators with hysterisis
tracking. The digitized signals are called D1-D11.
An internal correction and synchronization module
allows the composition of a true 16 bit Gray code by
merging the data bits of (1) and (2) by still keeping the
code monotonic.
There is a Gray code correction feature for this encoder.
This Gray code correction can be disabled/enabled by
the pin KORR.
The gain and offset conditioning value of the sine and
cosine signals are preloaded on-chip by factory. This
will compensate for mechanical sensor misalignment
error.
Features
• Minimum mechanical alignment during installation
• Two Sine/Cosine true differential outputs with 1024
periods for unit alignment
• Integrated highly collimated illumination system
• 11 digital tracks plus 2 sin/cos tracks generate
precise 16 bit Gray code
• Ultra fast, 1 µs cycle for serial data output word
equals 16 MHz
• On-chip interpolation and code correction
• MSB can be inverted for changing the counting
direction
• Internally built-in monitor track for tracking the light
level of the LED.
• Watch dog with alarm output
• –25°C to +85°C operating temperature
Applications
• Rotary application up to 16 bit/360° absolute
position
• Linear positioning system
• Cost effective solution for direct integration into
OEM systems