Using an LM2917 freq to dc converter: (https://www.electro-tech-online.com/custompdfs/2008/11/LM2907PDF.pdf). (2917 IS ALSO COVERED IN THIS FILE) Converting pulses to dc voltage, then outputing that dc volatge to a TLC0831 analog to digital converter (https://www.electro-tech-online.com/custompdfs/2008/11/tlc0831.pdf). Output from A/D is then read and stored in a Parallax BS2 microcontroller, which uses a PIC16C57C as its main chip.
Using an oscilloscope, I've noticed that the output from the LM2917 is not very steady, it comes out in waves that slope upward and downward at about the same rate as the input pulses, which are less than 100pps.
How can I make the 2917 output smoother?
A filter capacitor somewhere?
I tried putting a 10MFd cap. across the output, and I think I ruined the 2917 by doing so. Now I get nice square wave pulses as an output. Perhaps I shouldn't have done that.![Eek! :eek: :eek:](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
Patrick
Using an oscilloscope, I've noticed that the output from the LM2917 is not very steady, it comes out in waves that slope upward and downward at about the same rate as the input pulses, which are less than 100pps.
How can I make the 2917 output smoother?
A filter capacitor somewhere?
I tried putting a 10MFd cap. across the output, and I think I ruined the 2917 by doing so. Now I get nice square wave pulses as an output. Perhaps I shouldn't have done that.
Patrick