3.2 I/O Signal Connections
3.2.3 I/O Circuits
3-8
3.2.3
I/O Circuits
Sequence Input Circuits
This section describes CN1 connector terminals 15-14 (Homing Deceleration Switch Input).
The output circuit for the Homing Deceleration Switch signal from the host controller can be
either line-driver output or open-collector output. These are shown below for each type.
The wiring specifications for CN1 connector terminals 15-14 and 40 to 47 are different.
Wire the terminals according to the information described in this section (Sequence Input Cir-
cuits).
The SERVOPACK may fail if the terminals are wired incorrectly.
Line-Driver Output Circuit
Open-Collector Output Circuits
(12-V Power Supply in SERVOPACK)
•
Precaution When Host Controller Uses Open-Collector Output with User-Supplied Power Sup-
ply
The SERVOPACK may fail depending on the relationship between the pull-up voltage (Vcc) and
the pull-up resistance (R1). Before you wire the circuits, confirm that the specifications of the
host controller satisfy the values shown in the following table.
Important
150
Ω
4.7 k
Ω
Applicable Line Driver:
S
N75AL
S
174 from Texa
s
In
s
trument
s
or equivalent
Ho
s
t controller
S
ERVOPACK
2.8 V ≤ (High level − Low level) ≤
3
.7 V
If the above formula i
s
not
s
ati
s
fied, the input
s
to the
S
ERVOPACK will be un
s
table, and the Home Deceleration
S
witch Input may be identified a
s
ON even though the
s
witch ha
s
not been turned ON.
S
ERVOPACK
Ho
s
t controller
PL
3
terminal
0 V
+12 V
4.7 k
Ω
150
Ω
ON:
1.5 V max.
Approx.
9 mA
Important
Pull-Up Voltage (Vcc)
Pull-Up Resistance (R1)
Output Current (i)
24 V
1.8 k
Ω
to 2.7 k
Ω
20 mA max.
12 V max.
820
Ω
to 1.5 k
Ω
5 V max.
180
Ω
to 470
Ω
Circuit Example for Open-Collector Outputs
S
ERVOPACK
VF = 1.5 V to 1.8 V
Vcc
Tr1
VF
R1
i
Ho
s
t controller
150
Ω
4.7 k
Ω
Pull-up
