IC-HF Datasheet, PDF (11/36 Pages) IC-Haus GmbH – 6-CH. ENCODER LINK, RS-422 DRIVER/RECEIVER

iC-HF
preliminary
6-CH. ENCODER LINK, RS-422 DRIVER/RECEIVER
FUNCTION DESCRIPTION
Rev C1, Page 11/36
iC-HF has 4 function modes. Each function mode com-
bines the unidirectional and bidirectional channels with
a specific configuration. iC-HF can be operated as a
six channel line driver, as a 6 lines transceiver with
BiSS/SSI connectivity or as a bus capable BiSS slave
transceiver inserted in a BiSS bus structure. The 4
function modes are the following:
• A/B/Z and U/V/W
• A/B/Z and BiSS/SSI
• BiSS bus structure
• BiSS bus loopback
Selection of iC-HF’s function mode is set by the pins
FMSEL2 and FMSEL1:
FMSEL2
0
0
1
1
FMSEL1
0
1
1
0
MODE
A/B/Z and U/V/W
A/B/Z and BiSS/SSI
BiSS bus structure
BiSS bus loopback
Table 4: Mode Configurations
FMSELx pins include pull-down resistors. When there
is no external connection to FMSELx pins, A/B/Z and
U/V/W is the default selected mode.
A/B/Z and U/V/W Mode
If FMSEL2 = 0 and FMSEL1 = 0, iC-HF is configured
in A/B/Z and U/V/W mode. A/B/Z and U/V/W mode
is the default mode. In this mode all 6 channels work
as line drivers. Single ended input signals at pins X1
to X6 are converted into differential output signals at
pins Q1/NQ1 to Q6/NQ6. Output signals follow RS-422
standard.
Output Enable pin ”OEN” must be set hi to enable differ-
ential output signals. When working as 6-channel line
driver, pins NX1 to NX3 are disabled. An example of
iC-HF working as a 6-channel line driver is presented
in figure 8.
VDDS
1 μF
GNDS
VDD
3..5.5V
REVERSE POLARITY PROTECTION GND
1 μF
X1
NX1
X2
NX2
X3
NX3
X4
X5
X6
PTC
ECM
OEN
FMSEL1
FMSEL2
NERRI
BYP EBIS TRI
CONTROL
LOGIC
OVT
PoDo
1
RS422 Output
Q1
TRI
NQ1
Q2
RS422 Output
NQ2
Q3
RS422 Output
NQ3
Q4
RS422 Output
NQ4
Q5
RS422 Output
NQ5
Q6
RS422 Output
NQ6
BYPR
ENCODER LINK
REQUEST
DETECTION
OVT
PoDo
OVERTEMP
POWER DOWN
Q1
NQ1
NERR
iC-HF
gether, 9 lines are available in A/B/Z and U/V/W mode
in Encoder Link State.
To enter Encoder Link State, ECM pin must be set hi
and two signals must be input at pins Q1 and NQ1
following a specific timing sequence. This timing se-
quence is called Encoder Link Sequence. More infor-
mation about entering Encoder Link State on page 20.
VDDS
1 μF
GNDS
X1
NX1
VDD
3..5.5V
REVERSE POLARITY PROTECTION GND
1 μF
Encoder Link
Q1
NQ1
X2
Encoder Link
Q2
NX2
NQ2
X3
Encoder Link
Q3
NX3
NQ3
X4
X5
X6
PTC
ECM
OEN
FMSEL1
FMSEL2
NERRI
BYP EBIS TRI
CONTROL
LOGIC
OVT
PoDo
1
Encoder Link
Q4
NQ4
Encoder Link _Q5
NQ5
Encoder Link
Q6
NQ6
BYPR
ENCODER LINK
REQUEST
DETECTION
OVT
PoDo
OVERTEMP
POWER DOWN
Q1
NQ1
NERR
iC-HF
Figure 9: A/B/Z and U/V/W mode, 9 lines in Encoder
Link State
Figure 8: A/B/Z and U/V/W mode, 6 channel line
driver
In A/B/Z and U/V/W mode it is possible to enter En-
coder Link State. If Encoder Link State in this mode
is entered, signals at pins X1 to X6 are directly linked
to output pins Q1 to Q6. Input signals at pins NX1 to
NX3 are also linked to output pins NQ1 to NQ3. Alto-
A/B/Z and BiSS/SSI mode
If FMSEL2 = 0 and FMSEL1 = 1, iC-HF is configured
in A/B/Z and BiSS/SSI mode. In A/B/Z and BiSS/SSI
Mode channels 1, 2 and 3 work as line drivers, similar
to A/B/Z and U/V/W mode.
Channels 4, 5 and 6 are used for implementing
BiSS/SSI communication in RS-422. This allows com-