Opto Isolated System Outputs - STA...STD
There are four digital isolated output ports on both external and internal system connectors. The ports are named STA, STB, STC, and STB.
Opto isolated system outputs
Each port exposes two pins named respectively STx+ and STx-; with x = {A, B, C, D}.
The pins STx+ and STx- are connected respectively to the collector and the emitter of the NPN phototransistor of the opto coupler. When turned ON, the current flows from pin STx+ to pin STx- via the transistor.
The opto-coupler turn off time is enhanced by an external circuit.This output port emulates a potential free polarized solid-state contact. The contact remains in the open state during board initialization procedure.
DC characteristics
Parameter |
Test condition |
Min |
Typ. |
Max |
Units |
Maximum open contact voltage |
- |
|
|
60 |
V |
Close - current range |
- |
0,3 |
|
6 |
mA |
Close - voltage drop |
Iin= 1 mA |
|
|
0,71 |
V |
Iin = 6mA |
|
|
0,85 |
V |
|
Open - Leakage current |
Vin = 10V |
|
|
5 |
µA |
Rise time |
1 mA < Iin < 6 mA |
|
|
3.8 |
µs |
Fall time |
|
|
3 |
µs |
|
Isolation voltage |
|
|
|
500 |
V |