17
Rev. 1.0
8/26/2015
STM11 Hardware Manual
3.3.3 X3/EN & X4/AR Digital Inputs
The diagram below shows how to connect the X3/En & X4/AR Inputs to commonly used device.
Note: X3/EN & X4/AR inputs have been internally pulled up to logical 3.3 VDC
Note: If the input voltage is between 5-24 VDC, or the input is not connected, the logic
state of that input is HIGH. If the input voltage is below 1 VDC, the logic state of that input
is LOW.
DSP
GND
GND
10K
+
3.3V
10pF
50K
X3/EN
Inside drive
X4/AR
STM11
EN
Connecting to Controller with Sinking Outputs
Note: Souring Outputs are not compatible to inputs X3/EN and X4/AR
Connecting to NPN type Proximity Sensor
Note: PNP type Proximity Sensor is not compatible to inputs X3/EN and X4/AR
AR
GND
X3/EN
X4/AR
V-
STM11
OUT
OUT
GND
X3/EN
X4/AR
V-
5-24VDC
NPN
Sensor
5-24VDC
NPN
Sensor
STM11
X4/AR
X3/EN
+
-
15 to 30V
Power
Supply
Using Mechanical Switches
V+
