Search found 2 matches
- Wed Mar 26, 2014 4:12 pm
- Forum: Test Equipment
- Topic: Hobby Components USB 8CH 24MHz Logic Analyser (HCTEST0006)
- Replies: 102
- Views: 171336
Re: Hobby Components USB 8CH 24MHz Logic Analyser (HCTEST000
The Input circuit is an HC245 but it is powered from 3.3 V not 5V. The input circuit has 100 ohm resistors in series with each input and 100K bias resistors between each 245 input and 3.3 V. I presume they are there to stop open circuit inputs from damaging the 245. The 100 ohm resistors would appea...
- Tue Mar 25, 2014 11:59 am
- Forum: Test Equipment
- Topic: Hobby Components USB 8CH 24MHz Logic Analyser (HCTEST0006)
- Replies: 102
- Views: 171336
Re: Hobby Components USB 8CH 24MHz Logic Analyser (HCTEST000
Just bought one of these. I would like to know what the threshold and safe positive and negative input levels are for this device.