XTR115：XTR115第8引脚输出驱动电流

dong.liu

Prodigy 10 points

Part Number: XTR115
Other Parts Discussed in Thread: XTR117, XTR116

请XTR115第8引脚输出驱动电流是多大？

over 1 year ago

0 Clemens Ladisch over 1 year ago

Guru 298820 points

The typical short-circuit current is 12 mA, so your current should be much lower than that.

The curve at the bottom of p. 4 does not go beyond 4 mA. The first paragraph on p. 6 says that you should not go above 3.7 mA if you want to be able to reach the minimum loop current of 4 mA.

+1 Raymond Zhang1 over 1 year ago

TI__Guru 63291 points

Hi Dong,

Thanks for Clements reply!

dong.liu said:
请XTR115第8引脚输出驱动电流是多大？

Please follow Clements suggestions. XTR115/XTR116/XTR117 are all part of 2-wire 4-20mA current loop transmitters, where the input signals are required to "float" and referenced to IRet pins only in a design.

Only one true GND node is allowed in the 2-wire, 4-20mA current loop transmitter architecture, typically the GND is allocated at the Vloop or Vsupply power source side (floating Vloop supply will cost more). All other onboard voltage references and input signals are referenced to pin3 or Iret node. The sum of all current branches within the loop can not exceed 3.7mA at pin4, when the total current exits from the node at Vin = 0V input signals w.r.t. Iret pin. Typically, the Vin is configured from 0V to 5V (w.r.t. Iret), the output current is converted from Vin (DC or AC) --> 4mA to 20mA (DC or AC signal) which are linearly proportional of the V-to-I converter.