SkyWave IDP-680, Руководство по оборудованию

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IDP 600 Terminal Series - Hardware Guide
© SkyWave Proprietary 13 T200, Version 02
3.3.1 Digital Input
Figure 12 shows a schematic of the I/O when configured as a digital input.
Figure 12 Digital Input
Input Type S1 S2
With weak pull-down Open Open
With pull-down Open Closed
With pull-up Closed Open
The input specifications are provided in the table below.
Parameter Minimum Typical Maximum Units
Input low range -10 - 1.05 V
Input high range 1.95 - 150 V
Input current with weak pull-down
(weak 1 MΩ pull-down still in place);
V
in
= 3.0 V
- 3 - µA
Input source current with pull-up
(V
in
= 0.0 V)
- 75 - µA
Input sink current with pull-down
(V
in
= 3 to 150 V)
- 80 - µA
INPUT
DIGITAL
1k
3V
ARM PROCESSOR
1M
3V
1nF
1k
3V
LIMITER
3V
S1
40k
S2
40k