SkyWave IDP-680 - Digital Output; Figure 13 Digital Output

IDP 600 Terminal Series - Hardware Guide
T200, Version 02 14 © SkyWave Proprietary
3.3.2 Digital Output
Figure 13 shows a schematic of the I/O when configured as a digital output. It must be
noted that I/O 04 is the only I/O with built-in short circuit protection for open drain
outputs.
Figure 13 Digital Output
Push-pull
S1 = Open
Open drain
S1 = Closed (Low Impedance)
S1 = Open (High Impedance)
The following tables describe the output specifications.
Push-pull
In the push-pull configuration the output is driven directly from the microprocessor.
Parameter
Minimum
Typical
Maximum
Units
Output high voltage - open circuit
2.85
3.0
3.15
V
Output high voltage (sourcing 25 µA)
2.80
-
-
V
Output low voltage (sinking 25 µA)
-
-
0.05
V
Open Drain (I/O 01 to I/O 03)
Parameter
Minimum
Typical
Maximum
Units
Sink current (do not exceed)
-
-
250
mA
Voltage (active drawing at 250 mA)
-
-
2.56
V
Protected Open Drain (I/O 04 only)
Parameter
Minimum
Typical
Maximum
Units
Sink current (current limited)
-
-
300
mA
Voltage at 250 mA
-
-
3.09
V
I/O4
2R
S1
I/O1
1M
1k
3V
1nF
3V 3V
ARM PROCESSOR
OUTPUT
DIGITAL
I/O2
I/O3
1k
3V
LIMITER