IC-MN Datasheet, PDF (31/59 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 D1, Page 31/59
4. Transmission of the synchronized position value.
The transmitted NON_CTR counts as part of the
current conversion.
MODE_ST Codes 0x05, 0x06, 0x7
The processing time is low as "old" data is transmitted,
the time of sampling is, however, known (NB: The data
from the first readout is invalid following a SOFT_RES).
The conversion procedure is as follows:
1. With a data readout: immediate transmission of
the data from the last readout cycle including the
relevant NON_CTR
2. With a data readout: start of a new conversion
and providing of data for the next data readout
cycle. NON_CTR is output directly at the NERR
pin.
Principle PPR And Bit Length Dependencies
With a nonius system with three tracks UBL_M must be
set so that it is at least as large as the maximum value
of MAX(UBL_S+SBL_S, UBL_N+SBL_N). If only two
tracks are used, UBL_S and SBL_S must be set to
zero. UBL_M must then at least match the maximal
value of MAX(UBL_N+SBL_N).
The necessary number of signal periods per revolution
for the individual tracks is then determined by the se-
lected used bit lengths:
Track
Master
Segment
Nonius
Required signal periods
2^UBL_S+UBL_N
2^UBL_S+UBL_N − 2^UBL_N
2^UBL_S+UBL_N − 1
MODE_ST Codes 0x08, 0x09, 0xA
The processing time is low and the time of sampling
not precisely known. The conversion procedure is as
follows:
1. Regardless of the data readout: permanent
background conversion
2. With a data readout: transmission of current
data. Each NON_CTR is output directly at the
NERR pin. In data transmission a NON_CTR er-
ror is only signaled when the error occurs during
the relevant nonius calculation.
MODE_ST Code 0x0B
This mode can be used in systems in which sampling
must be synchronized to a frequency determined ex-
ternally and independent of the data readout cycles.
The conversion procedure is as follows:
1. A conversion with nonius synchronization is trig-
gered via pin T3. NON_CTR is output directly at
the NERR pin.
2. With a data readout the most recent conversion
data triggered by pin T3 is transmitted including
the relevant NON_CTR.
The following tables show the possible settings and
required number of signal periods. The total physi-
cal angle resolution in nonius mode is obtained from
the sum of UBL_M+UBL_S+UBL_N. At the same time
the bit lengths set for synchronization determine a limit
up to which a nonius calculation is possible. This limit
is given in Table 45 as the maximum tolerable phase
deviation which may occur between the segment and
master track or nonius and master track (with reference
to the electrical 360° period of the master signal).
Bits/Track
Signal periods/Turn
Physical
resolution ^a)
UBL_S UBL_N Master Segm. Nonius min ^b) max
2
2
16
12
15
2+2+4 2+2+13
3
2
32
28
31
2+3+5 2+3+13
3
3
64
56
63
3+3+5 3+3+13
4
3
128 120 127 3+4+6 3+4+13
4
4
256 240 255 4+4+6 4+4+13
5
4
512 496 511 4+5+7 4+5+13
5
5
1024 992 1023 5+5+7 5+5+13
6
5
2048 2016 2047 5+6+8 5+6+13
6
6
4096 4032 4095 6+6+8 6+6+13
a_{) For configuration of the output data length, see Table 51}
b_{) For the minimum data length SBL_x = 0x02 is assumed}
Table 43: Settings for 3-track nonius mode
Bits/Track Signal periods/Turn Physical resolution ^a)
UBL_N Master Nonius min ^b)
max
4
16
15
4+6
4+13
5
32
31
5+7
5+13
6
64
63
6+8
6+13
a_{) For configuration of the output data length, see Table 51}
b_{) For the minimum data length SBL_x = 0x02 is assumed}
Table 44: Settings for 2-track nonius mode