Interpreting circuit correctly 1

[culloekee]

14V source to a 5k resistor to ground also goes to input of line driver. With 5k connected to ground is input to driver 0V and does that input go to 14V if the ground is removed?

 

[MacGyverS2000]

If 14V is applied, the input is 14V (assuming you can supply enough current).

Dan - Owner

http://www.Hi-TecDesigns.com

 

[zappedagain]

14V / 5K = 2.8 mA. As long as your source can provide 2.8mA of current, you will have 14V on your line driver input. If it can't you will have a lower voltage. 5k * 1mA = 1V for example.

If you disconnect the source you will have 0V on your input. Without the 5k you would have a floating input that can easily pick up noise and give you lots of random data (chatter) on your line driver output. Unless your line driver has internal circuitry to make sure this doesn't happen.

Grounds are very important. If you 'lose' the ground connection at your line driver there is a good chance your line driver may be damaged. I know of one junior engineer who powered up a custom ASIC before making ground connections; the device was damaged beyond repair.

Z