IC-MN_16 Datasheet, PDF (2/62 Pages) IC-Haus GmbH – 25-BIT NONIUS ENCODER WITH 3-CH. SAMPLING 13-BIT Sin/D INTERPOLATION

iC-MN 25-BIT NONIUS ENCODER
WITH 3-CH. SAMPLING 13-BIT Sin/D INTERPOLATION
Rev F2, Page 2/62
DESCRIPTION
Encoder device iC-MN is a 3-channel, simultaneous
sampling sine-to-digital converter which interpolates
sine/cosine sensor signals using a high precision SAR
converter with a selectable resolution of up to 13 bits.
Each input has a separate sample-and-hold stage
which halts the track signal for the subsequent se-
quential digitization. Various 2- and 3-track Vernier
scale computations (after Nonius) can be configured
for the calculation of high resolution angle positions;
these computations permit angle resolutions of up to
25 bits.
The absolute angle position is output via the serial
Interface with clock rates of up to 4 Mbit/s (SSI com-
patible; up to 10 Mbit/s with BiSS C protocol). The
RS422 transceiver required to this end is integrated
on the chip and has both a differential clock input and
a differential line driver for data output.
Programmable instrumentation amplifiers with a se-
lectable gain and offset and phase correction can be
adjusted separately for each channel; these allow dif-
ferential or single-ended input signals. At the same
time the inputs can either be set to high impedance for
voltage signals from magneto resistor sensor bridges,
for example, or to low impedance for adaptation and
use with photosensors which provide current signals,
for instance. This enables the device to be directly
connected up to a number of different optical and
magnetic sensors.
For the purpose of input signal stabilization the con-
ditioned signals are fed into signal level controllers
featuring current source outputs of up to 50 mA (mas-
ter channel) and of up to 10 mA (for the nonius and
segment channels each). These ACOx source pins
either power the LEDs of an optical encoder or the
magneto resistor bridges of a magnetic encoder. If the
control thresholds are reached this event can be re-
leased for alarm messaging using the serial interface
or the NERR output.
Both major chip functions and sensor errors are also
monitored and can be enabled for alarm indication. In
this manner typical sensor errors, such as signal loss
due to wire breakage, short circuiting, dirt or aging,
for example, can be signaled by alarms.
The device features further digital encoder functions
covering the correction of phase errors between the
tracks, for example, or the zeroing or presetting of a
specific position offset for data output. Using the SSI
master also integrated on the chip position data from
multiturn sensors, provided by a second iC-MN, for
example, can be read in and synchronized.
iC-MN is protected against a reversed power supply
voltage; the integrated supply switch for loads of up
to 20 mA extends this protection to cover the over-
all system. The device is configured via an external
EEPROM.
The device described here is a multifunctional iC that contains
integrated BiSS C interface components. The BiSS C process is
protected by patent DE 10310622 B4 owned by iC-Haus GmbH
and its application requires the conclusion of a license (free of
charge).
Download the license at
www.biss-interface.com/bua