Test Products International 460 - Manual (Page 22)

Glitch Capture
The tpi Scope Plus 460 incorporates this feature for capturing intermittent or single event voltage
spikes occurring in a circuit. The spike is automatically detected, captured, and displayed for
analysis on the screen.
To perform this task as a test, you will need a signal generator with a spike or glitch generating
capability, or a means of imposing a glitch onto an otherwise stable signal.
With Channel A on the 460 active, connect the Common and Probe Lead A to a signal source
(Sine Wave preferred), and proceed with the following steps:
1. Click SCOPE, then select A=DCU, Mode=Glitch, B=Off. Then select ENTER
2. Use the up and down keys to center, or lower the waveform (-the spike will usually be
positive in test cases). Then introduce the spike (-this is usually a button on many test
signal generators).
3. If the 460 is performing correctly, you should now have the glitch on your screen,
complete with leading and trailing edges so that rise time as well as other parameters
can be measured.
4. Exit the glitch condition by selecting SCOPE, then change MODE = NORM, then press
ENTER.
Saving Screens
You can save any screen capture from Channel A, Channel B, or two instances of both channels
simultaneously. They can be recalled to the screen, or made available to your computer if you
also have the RS232 software option.
As an example of simultaneous capture, connect the Common and Probe Lead Ch A to one signal
source, then the Probe lead Ch B to a different signal source, and proceed with the following
steps:
1. Click SCOPE, then select A=ACU, Mode=Glitch, B=ACU. Then select ENTER
2. Use the up and down keys in conjunction with the A & B Move boxes at the base of the
screen to position both waveforms
3. Press the SAVE key, select SCREEN 1, and then select ENTER
460 User s Guide Advanced Functions
C4-2