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I/O Interface
ConnectorTrigger input
Optocoupler interface
Optically isolated inputs and outputs.
Optocoupler basics
 Diagram of basic optocoupler function | An optocoupler is a device using optical path to transfer an electronic signal between two circuits. It basically consists of a photodiode beween pin 1 and 2 converting the input signal to light and a phototransistor converting the light again to electronic signal at pin 3 and 4. The optocoupler is useful in situations where one part of the circuit needs to be galvanically isolated from the other part to prevent damage or unwanted interference. It is used to prevent ground loops or to block voltage spikes. For effective use of the optocoupler it is important to control it using an independent power supply. When the external circuit is galvanically connected to the camera (eg. when reusing the camera's power to control the optocoupler), the optocoupler's protective function is eliminated. |
Optocoupler inputs
The iam camera camera is equipped with four optically isolated input lines. One input optocoupler is fully independent, the other three are connected with a common cathode (Section “I/O connector”) due to limited number of pins on the I/O connector. Each input line is protected by a current limiter circuit.
The optocoupler input's logical state is understood as logical 0 if no current is flowing through the optocoupler diode, logical 1 if current is flowing through the diode.
The optocoupler is guaranteed to be switched on (logical 1 status) when the voltage applied to the input is within range of 3.3 - 30V (tolerance 10%). It is guaranteed to be switched off (logical 0) when the applied voltage is under 2.0 V. The input status is undefined between 2V and 3 V,the input voltage must not exceed the 30V limit!
The input lines are using fast optocouplers: the propagation time is under 125 ns, for both rising and falling signal edge (assuming input signal with strongly steep edge). The exact switching speed may vary with temperature and the used input voltage level - the listed specifications are the worst case values.
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The optocoupler inputs have no protection against wrong polarity. Be sure to connect them always with correct polarity according to the documented wiring diagrams and connector pinouts. |
The optocoupler inputs are TTL compatible provided that the signal source is capable of supplying the input current of 7.5 mA.
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The optocoupler input lines are equipped with a debouncer to prevent generating unwanted input signals. |
Optocoupler outputs
The iam camera is equipped with three optically isolated output lines. One output optocoupler is fully independent, the other two are connected with a common collector (Section “I/O connector”) due to limited number of pins on the I/O connector.
After power up, the optocoupler outputs are in high impedance state and they remain in that state until reconfigured from the software interface. Whenever the optocoupler output is disconnected in the SW interface, it gets in high impedance status.
- optocoppler high impedance state: ist das so schon? Andreas Kramer | NET GmbHmartin.winterer (Unlicensed)
The optocoupler output's logical state is understood as logical 0 when its output transistor is in high impedance, logical 1 if it is in low impedance mode.
The rising edge (switching to logical 1) propagation time is 750 ns, the falling edge propagation time is under 25 µs. The exact switching speed may vary with temperature and the used input voltage level — the listed specifications are the worst case values.
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The optocoupler output work with operating voltage range of 3.3-30 V. The maximal switched output current is 100 mA per optocoupler, higher current could damage the optocoupler output circuit. |
Optocoupler parameters summary
Parameter | INPUT Value | Output Value | |
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Operating voltage | 3.3 - 30 V | 3.3 - 30 V |  |
Input current | 7.5 mA | < 100mA | |
External resistor requirement | No | Yes, output current must be limited to 100 mA | |
ON voltage level | > 4.5 V | ||
OFF voltage level | < 1.5 V | ||
OFF to ON delay | < 125 ns | 750 ns | |
OFF to ON rise time (10 to 90%) | 1.0-4.0 µs | ||
ON to OFF delay | < 125 ns | 2.4 – 25 µs | |
ON to OFF fall time (90 to 10%) | 9.0 – 140 µs | ||
OFF to ON jitter | ± 5 ns | ± 20 ns | |
ON to OFF jitter | ± 5 ns | ± 0.1 µs |
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Connector and cable description
14-pin DLP (dual-inline-pin) connector for digital i/o and power input. An adapter cable is available (see Section “Accessories”).
Connector Pinout TFM-107-02-L-DH.pdf | Mates Pinnout SFSD-07-XXX-G-XX.XX-SR |  | |
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Pinnout
Pin # | Signal | Schematic Name | note | FPGA | linux |
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1 | AUX_POWER | auxiliary power supply voltage | |||
2 | GND_P | auxiliary power supply Ground | |||
3 | IN_TRIGGER+ | Trigger +IN | ext_trigger_i | emio[0] (416)Optocoupler Input TRIGGER Anode | |
4 | IN_TRIGGER- | Optocoupler Input TRIGGER Cathode | |||
5 | IN_ENC1+ | ext_gpi0_i | emio[4] (420) | Optocoupler Input 1 Anode | |
6 | IN_ENC2+ | ext_gpi1_i | emio[5] (421) | Optocoupler Input 2 Anode | |
7 | IN_ENC3+ | direction by assembly option | ext_gpio0_i | emio[6] (422) | Optocoupler Output 3 Anode |
8 | IN_ENC_GND | Optocoupler 1-3 Input Cathode | |||
9 | OUT_GP1+ | ext_gpo1_o | emio[8] (424) | Optocoupler Output 1 Collector | |
10 | OUT_GP2+ | ext_gpo0_o | emio[7] (423)Optocoupler Output 2 Collector | ||
11 | OUT_GP_GND | Optocoupler Output 1-2 Emitter | |||
12 | OUT_STROBE+ | ext_strobe_o | emio[3] (419) | Optocoupler Output STROBE Collector | |
13 | OUT_STROBE- | Optocoupler Output STROBE Emitter | |||
14 | SGND_IO | Cable Shield |
Accessoires
Break-Out-Boards
Cable Assemblies
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