USB Digital Output Module – Solid State, Open Collector, Relay

USB Analog and Digital IO Modules

LucidControl USB IO Modules

  • Data acquisition and control

  • Cost effective and flexible

  • Platform independent

  • Windows® and Linux

  • Compatible with RPi and Beagle Bone

  • Clippable on DIN-Rail

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  • Industrial & home automation

USB Digital Input Module

USB Digital Input Module

LucidControl Product Series

  • 4 digital inputs

  • 3 voltage level options

  • Opto insulated contacts

  • Counters and edge detectors

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USB Digital Output Module

USB Digital Output Module

LucidControl Product Series

  • Opto insulated option

  • 4 digital outputs

  • Relay module option

  • Pulse width modulation and timers

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  • Switching and power control applications

USB Analog Input Module

USB Analog Input Module

LucidControl Product Series

  • Measurement range options

  • 4 analog inputs

  • e.g. 0 ~ 10 V or -10 ~ 10 V

  • 14 bit resolution

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  • Acquisition of sensor signals

USB Analog Output Module

USB Analog Output Module

LucidControl Product Series

  • 4 analog outputs

  • Output range options

  • e.g. 0 - 10 V or 4 - 20 mA

  • 12 bit resolution

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  • 4 - 20 mA current interfaces

USB RTD Input Module

USB RTD Input Module

LucidControl Product Series

  • 4 Pt1000 / Pt100 RTD inputs

  • Temperature range: -180 ~ 180 °C

  • 0.1 °C resolution

  • Heat control applications

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  • Logging of temperatures

Types of Digital Output Devices

Digital outputs are used for many purposes and because of this they are carried out in different manners. The following selection guide describes the 3 options which are available for LucidControl USB digital output modules.

Solid State Relays

LucidControl DO4-I - Principle of Solid State Outputs

For most applications solid state relays (SSR) are the best option since they are optical and potential insulated and allow fast and continuous switching which is e.g. necessary when a pump has to be controlled in order to regulate the water flow through a hydraulic system. Pumps are controlled this way very often while a pulse width modulation is used i.e. the portion of switched on and switched off time is changed.

The figure beside shows the DO4-I module with it 4 solid state relay outputs. The power consumers are shown as lamps.

Solid state relays are preferable because they insulate the load to switch and the USB device including the host computer optically giving a higher protection of the computer. Moreover all outputs of the DO4-I module are completely independent and there are no common contacts and polarity of the signal does not play a role.

All outputs of the LucidControl DO4-I module are rated with 0.7A and 30V DC

Mechanical Relays (SPDT Switch)


The pictures beside show the principle of mechanical SPDT “single pole double throw” relays. These relays allow switching of power consumers as well as of signals. Since the lifetime of mechanical relays is limited regarding switching cycles they are not suited for continuous switching.

SPDT relays are insulated and potential free. Any output can be seen as a complete independent unit.

One of the advantages of SPDT relays is the fact that they are real mechanical switches and it is possible to switch measurement signals like RTD sensors without distortion.

Moreover the picture shows that the DO4-S module has a 12 pin IO-Connector. The reason for this is that all outputs provide 3 terminals. The common contact is toggled between the normally opened (NO) and the normally closed (NC) contact. This makes it possible to select one out of two signals.

Open Collector Outputs


open collector

Open collector outputs use a transistor which connects a terminal to ground. These switches have a single ground connection common for all 4 outputs of the DO4-O module and they do not provide an optical insulation like the two other options do.

Beside of these drawbacks open collector outputs have one important advantage – they are very fast. This makes them a great option e.g. for dimming lamps and LEDs. For this purpose the DO4-I module is not fast enough, since the solid state relays are limited in timing which would result in detectable flickering of the light.

By using the DO4-O module LEDs and lamps can be switched on and for only a few microseconds which avoids flickering.