IC-MHL200 Datasheet, PDF (27/33 Pages) IC-Haus GmbH – 12-BIT LINEAR / ROTARY POSITION HALL ENCODER

iC-MHL200
12-BIT LINEAR / ROTARY POSITION HALL ENCODER
Rev C1, Page 27/33
In the SSI mode the absolute position is output with 13
bits according to the SSI standard. However, in the SSI
mode it is not possible to vary the parameter set. The
data is transmitted as reduced Gray code, e.g. after
converting into binary code, the data range is symmet-
rical to the center of the number string. For example,
with a set resolution of 360 data values between 76 and
435 are transmitted.
0x43 contains the three least significant bits of the multi-
turn resolution, what is here always 000 and five bits of
the singleturn resolution as is the data length DLEN of
the transmitted sensor data in accordance with the set
resolution. The sensor data is transmitted right-justified
and filled with preceding zeros on smaller resolutions
than 12 bit. The following table shows the data length
according to the resolution.
Figure 28: SSI protocol, data GRAY-coded
The register range 0x00 to 0x0F is equivalent to the set-
tings with which the IC can be parameterized. The set-
tings directly affect the corresponding switching parts.
It is important to note that test register 0x0E can only be
written to when pin VZAP is connected to VPD. When
VPD > 6 V, write access to the test register is ignored.
Register 0x0F can be configured at potentials V(VZAP)
> Vt(VZAP)hi.
The range 0x10 to 0x1F is read-only and reflects the
contents of the integrated zapping diodes. Following
programming the data can be verified via these ad-
dresses. After the supply voltage is connected, the
contents of the zapping diodes are copied to the RAM
area 0x00 to 0x0F. Then the settings can be overwrit-
ten via the BiSS interface. Overwriting is not possible if
the CFGPROT bit is set.
Errors in the module are signaled via the error message
output NERR. This open-drain output signals an error if
the output is pulled against VND. If the error condition
no longer exists, then the pin is released again after
a waiting time of approximately 1 ms. If the integrated
pull-up resistor is deactivated with DPU = 1, then an
external resistor must be provided. With DPU = 0 it
brings the pin up to the high level again.
DPU
Value
0x0
0x1
Addr. 0x04; bit 6
Function
Pull-up activated
Pull-up deactivated
Table 30: Activation of NERR pull-up
With the BiSS profile ID, the data format of the sensor
can be requested. Reading the BiSS profile ID results
0x2C in address 0x43, which identifies BiSS Profile
BP1 and two most significant bits of the multiturn res-
olution, what is here always 00. Reading the register
DLEN
Value
0
1
2
3
4
5
6
7
8
9
10
11
12
Addr. 0x43; bit 3:0
Length
n/a
n/a
CFGRES = 00000000, 4
CFGRES = 00000001, 8
CFGRES = 0000001x, 12 to 16
CFGRES = 000001xx, 20 to 32
CFGRES = 00001xxx, 36 to 64
CFGRES = 0001xxxx, 68 to 128
CFGRES = 001xxxxx, 132 to 256
CFGRES = 01xxxxxx, 260 to 512
CFGRES = 10000000, 1 024
CFGRES = 10000001, 2 048
CFGRES = 10000010, 4 096
Table 31: Data length
Note: With CFGRES = 10000010, 4 096 and using
BiSS protocol the device provides a BiSS Profile ID
0x2C 0x0C (0x2C in address 0x42 and 0x0C in ad-
dress 0x43) that is "BiSS Profile BP1 Standard Rotary
Encoder" conform.
The status register provides information on the status
of the module. There are 5 different errors that can
be signaled. Following unsuccessful programming of
the zapping diodes, the bit PROGERR is set. If an
attempt is made to read the current position via the
BiSS interface during the start-up phase, an error is sig-
naled with ERRSDATA, as the actual position is not yet
known. The ERRAMAX bit is output to signal that the
amplitude is too high, while the ERRAMIN bit signals
an amplitude which is too low, caused, for example, by
too great a distance to the magnet. If the NERR pin
is pulled against VND outside the module, this error is
also signaled via the BiSS interface. The ERREXT bit
is then equal to 1. The error bits are reset again after
the status register is read out at the address 0x77. The
error bit in the data word is then also read in the next
cycle as 0.