20-151-0178 Rabbit Semiconductor, 20-151-0178 Datasheet - Page 61

• Manufacturer Part Number: 20-151-0178
• Description: CABLE CONVERTER RS-232 TO USB
• Manufacturer: Rabbit Semiconductor

Specifications of 20-151-0178

• Accessory Type: USB to RS232 Adapter
• Product: Microcontroller Accessories
• For Use With/related Products: Rabbit-based Boards
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 20-151-0178; 316-1181

4.3.13.3 Analog Input 4-20 mA
This section presents the circuit schematic and the characteristics for the 4-20 mA analog input.
This analog input provides a simple interface for industry standard 4-20 mA devices. It is a passive input
and the device must either supply the loop current or be wired in series with a supply to operate correctly.
The loop is formed by using the input pin as the SIG+ line and the ground pin as the SIG- or signal return.
A design consideration for choosing the appropriate ADC circuit for your application is the fact that cur-
rent is preferred over voltage in noisy industrial/control environments where the transmission of low-
amplitude, low-frequency signals must travel significant distances. This is because the current stays con-
stant over the length of the cable.
Figure 4-27 Analog Input 4-20 mA Circuit Schematic
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Table 4-23. ADC 4-20 mA Characteristics
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