Digital Output Wiring

Digital Output Wiring¶

Digital output has an open collector switching transistor with common IO Ground.
In most cases a power source for external device must be provided.

Connecting Digital OUTPUT to a NPN-compatible PLC device input (biased)¶

Output State	Output switch state	Input state
ON	Sourcing current	Pull up (energized)
OFF	Relaxing	Not energized

Figure 1. - Connecting Digital OUTPUT to a NPN-compatible PLC device input (biased)

Important Note:
If using this configuration take into account that Common Ground pole is biased by power supply also for Digital Input!

Connecting Digital OUTPUT to a NPN-compatible PLC device input¶

This type of connection is possible only when opto-isolated input is used (bidirectional in some cases) or when only one general opto-isolated input is used.

Output State	Output switch state	Input state
ON	Sourcing current	Pull down (energized)
OFF	Relaxing	Not energized

Figure 2. - Connecting Digital OUTPUT to a NPN-compatible PLC device input - more bidirectional inputs used

NOTE:
In this case bidirectional opto-isolated input must be used

Figure 3. - Connecting Digital OUTPUT to a NPN-compatible PLC device - single input

Connecting Digital OUTPUT to a PNP-compatible device¶

Output State	Output switch state	Input state
ON	Sinking current	Not energized
OFF	Relaxing	Pull up (energized)

Figure 4. - Connecting Digital OUTPUT to a PNP-compatible device

Pull up resistor might be calculated as follow:
R=(Vpsu - Vinput) / Iinput

Where:
Vpsu - power supply voltage. Must be higher than required input amplitude
Vinput - required input amplitude
Iinput - input driving current (corresponding to input amplitude)

NOTE:
Take care about appropriate resistor power rating P(R)>(Vpsu - Vinput) * Iinput

Output Wiring Example: LED Driving¶

LED might be driven directly by camera digital output.
Only series resistor must be used to set LED current.

Figure 5. - LED Driving

LED series resistor might be calculated by following equation:

R=(Vpsu - Voutput - Vled) / Iled

Where:
Vpsu - power supply voltage (5V to 24V)
Voutput - voltage across digital output pins (see.Output transfer characteristic)

Vled - LED forward voltage (see table below)
Iled - LED current

NOTE:
Take care about appropriate resistor power rating P(RES)=Iled*Iled*R

Typical LED forward voltage

LED Colour	Vled (typ.)	Vled (max.)	Note
Standard Red	1.7V	2.1V
Super Bright Red	1.85V	2.5V
Low power Red	1.7V	2.0V
Orange	2.0V	2.1V
Yellow	2.1V	2.2V
Green	1.9V	2.5V
Emerald Green	2.1V	2.7V
Blue	2.5V	3.7V
White	2.8V	3.8V
Infra-Red	1.3V	1.8V	Optocoupler

Output Wiring Example: Inductive load (Relay) Driving¶

Do not connect inductive load RL directly to Camera Digital Output.
Transistor has to be used to prevent damage of output.
See image below for possible inductive load driving.
Resistor R can be connected to Digital Outputs and power supply to provide necessary bias current for transistor.
You should also use external diode to protect transistor from over voltage while disconnecting inductive load.
Keep in mind that this connection has an inverted logic.
Current will flow through load at start of camera.

Figure 6. - Inductive load (Relay) Driving (inverted logic)

To get positive logic you can use second bipolar transistor.

Figure 7. - Inductive load (Relay) Driving (non-inverted logic)

Output Wiring Example: Driving trigger input of strobe controller¶

Digital output might be used to drive strobe controller according table below.

Driving trigger input of strobe controller

Trigger polarity	Opto-isolated controller input	Output delay	Wiring	Description
Positive edge	Yes	0.5us	Figure 1
Negative edge	Yes	0.5us	Figure 3
Positive edge	No	155us	Figure 4	Not recommended in cases when short delay time is required. Output delay is much longer than in other wiring examples. Use external pull up in case that no pull at controller input is used.
Negative edge	No	0.5us	Figure 4	Note that external pull up is not used in this case. Assume that internal pull up at the controller input is used.