Jan 23, 2005 #1 E extraord Member level 4 Joined Mar 5, 2004 Messages 68 Helped 8 Reputation 16 Reaction score 2 Trophy points 1,288 Activity points 553 the input signal frequency is very low, and the SNR is 10db.
Jan 23, 2005 #2 VVV Advanced Member level 5 Joined Nov 26, 2004 Messages 1,575 Helped 384 Reputation 768 Reaction score 88 Trophy points 1,328 Activity points 19,971 I don't know if this is similar to what you are looking for, but take a look at my replies to this post:
I don't know if this is similar to what you are looking for, but take a look at my replies to this post:
Jan 23, 2005 #3 FoxyRick Advanced Member level 4 Joined Jan 8, 2004 Messages 1,249 Helped 321 Reputation 640 Reaction score 277 Trophy points 1,373 Location England, UK Activity points 12,979 Some good info in the links given by VVV, also: 1. Make sure to use guard tracks/rings on the PCB around your signal input to minimise current leakage 2. Maybe look at circuits used to measure air ionisation - these work with very low currents FoxyRick.
Some good info in the links given by VVV, also: 1. Make sure to use guard tracks/rings on the PCB around your signal input to minimise current leakage 2. Maybe look at circuits used to measure air ionisation - these work with very low currents FoxyRick.
Jan 24, 2005 #4 J JPR Full Member level 1 Joined Aug 12, 2004 Messages 96 Helped 26 Reputation 52 Reaction score 11 Trophy points 1,288 Activity points 1,929 If you are looking for an instrument, try the keithley 6485 picoammeter.
Jun 13, 2005 #5 W windman Junior Member level 3 Joined Sep 13, 2004 Messages 26 Helped 0 Reputation 0 Reaction score 0 Trophy points 1,281 Activity points 282 You can use high imput impedance and low input leakage instrument OA to do that.
Jun 13, 2005 #6 V vdaniel Full Member level 4 Joined Oct 8, 2004 Messages 204 Helped 8 Reputation 16 Reaction score 0 Trophy points 1,296 Activity points 2,157 There is a great difference between "sensing" and "measurement". In the first case one needs to define what threshold he needs, in the second the tolerance. Varuzhan
There is a great difference between "sensing" and "measurement". In the first case one needs to define what threshold he needs, in the second the tolerance. Varuzhan