What is the current loop?
In the communication circuits, the current loop is an electrical signaling diagram that uses the power source and the current receiver. The voltage signal systems use the current converter to the voltage and the remote current receiver to send high -speed data over more distances. The current loop can use different current levels for analog and digital communication. The analog current loop usually uses a signaling level of 4- to 20 million (MA), which corresponds to the analog value. Integrated circuits on the printed circuit board Use a powered voltage scheme that is suitable for very short distances inside the circuit board. In the circuit controlled voltage, the receiver senses the voltage, which is very simple because there is a minimal distributed inductance and capacity that can limit the transmission of signal. When the voltage driver has to send to a remote location, which is more than a few meters away, the signal requires time to get to the receiver, and in some cases they may not even get to comeMači. Current levels for digital signals due to the nature of wire loops - "brand/space" or "you and zeros" - are usually twisted polarity. When compared, serial bus can use differential voltage units that use a twisted pair to send one bity at a time, and two wires in double end or balanced output will be used to send one bits.
The current loop in a similar application sends the current level proportional to the signal voltage and does not send the voltage directly. Any voltage at the end of the voltage transmitter will have to deal with several factors. These include the output impedance of the perimeter of the driver, distributed inductance and capacity and external electromagnetic noise.
The current driver in the current loop is able to compensate for wire performance and external noise. For example, if the current loop transmitter must send 12 mA to a remote receiver to indicate analog value will be inReceiver available at the same 12 mA, even if the wire resistance has changed. The reason is the principle of the control of the controlled current, in which the source intends to send 12 mA. If the loop characteristics change even quite quickly, the resulting current is still the same, as the source of the controlled current adapts accordingly.