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31.07.13 TB
22.10.14 TB
LTR-1200
User Manual
3.2.5 RS485
3.2.5.1
Pinout
RS485 Label Half-Duplex Connection
A
A
B
B
Y
Z
GND
3.2.5.2
Characteristic
Symbol Parameter
Comments
Min
Typ
Max Units
Digital Isolator Characteristics
V
ISO
Isolation Voltage
1
-
2.5
kV
Speed
Communication Speed (Baud Rate)
Software Setting
4800
1M
bps
V
PP
ESD Protection
Human Body Model
+-15 kV
Input Characteristics (Receiver)
V
TH
Differential Input Threshold Voltage
-200 -125 -30
mV
V
HYS
Input Voltage Hysteresis
15
mV
R
IN
Line Input Resistance
96
kΩ
Output Characteristics (Driver)
V
OD1
Differential Output Voltage, Loaded
R
L
= 100Ω (RS422)
2.0
3.6
V
V
OD2
Differential Output Voltage, Loaded
R
L
= 54Ω (RS485)
1.5
3.6
V
3.2.6 RS232
3.2.6.1
Pinout
Pin
Function
2
TxD (Data from LTR)
3
RxD (Data to LTR)
5
Signal Ground (GND)
other Not Connected
3.2.6.2
Characteristic
Symbol Parameter
Comments
Min
Typ
Max Units
Protection Characteristics
V
ISO
Isolation Voltage
1
-
2.5
kV
V
PP
ESD Protection
Human Body Model
+/-15 kV
Electrical Characteristics
Speed
Communication Speed (Baud Rate)
Software Setting
4800
1M
bps
V
OH
High-level Output Voltage
TxD at R
L
= 3kΩ to GND 5
5.5
V
V
OL
Low-level Output voltage
TxD at R
L
= 3kΩ to GND -5
-5.4
V
V
IT+
Positive Input Threshold Voltage
1.5
2.4
V
V
IT-
Negative Input Threshold Voltage
0.6
1.2
V
Summary of Contents for LTR-1200
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