Line driver is a converter of digital signals into a differential signal. The device is mostly used for retrofitting machines equipped with encoders or linear scales with OC, PP HTL output while a motion controller requires a differential signal. The line driver helps with devices not related to measuring systems. It is necessary in the situations when fast sending of 5V or 24V signals to a considerable distance in an environment filled with heavy distortion is required.
How does it work?
The fundamental task of a line driver is to change digital signals TTL/OC into a differential signal TTL. To further explain the process, it is better to explain each element separately.
- TTL digital signal
TTL digital signal, so Transistor-Transistor Logic, is made of bipolar transistors, defines digital 1 as when signal voltage is between 1.5 and 5V, and digital 0 as when a signal voltage is between 0V and 0.7V.
- OC digital signal
OC digital signal, so Optical Carrier transmission rates, are a standardized set of specifications of transmission bandwidth for digital signals that can be carried on Synchronous Optical Networking (SONET) fiber optic networks.
- Differential signal TTL
Differential signal TTL employs two complementary voltage signals in order to transmit one information signal (one information signal requires a pair of conductors; one carries the signal and the other carries the inverted signal).
Line driver has the exact opposite function to the line receiver, which is used to convert the differential signals TTL into digital signals TTL/OC. Matching both the systems – line driver and line receiver – allows the user to send 5V or 24V signals over long distances using the differential signal that is highly resistant to interference.
Examples of use
Line driver can be used to:
- Change of encoder’s signal that has OC (open collector) output type into the differential signal.
- Change of encoder’s signal that has Push-Pull output type into the differential signal.
Look also at:
Line Receiver – Universal converter of differential signals [TTL] into digital signals TTL or OC – a system that has exactly opposite functions – to change differential signal into TTL (5V) signal or OC (open collector) signal (GND control).
Matching both the systems (Line Driver + Line Receiver) you can send 5V or 24V signals over long distances using the differential signal which is highly resistant to interference.
