Agilent Technologies 54624A, 54621D, 54622D, 54622A, 54621A Threshold Accuracy Voltage Test Settings

Testing Performance

To verify digital channel threshold accuracy

7Press the oscilloscope User softkey, then turn the Entry knob ( ) on the front panel on the oscilloscope to set the threshold test settings as shown in Table 3-3.

Table 3-3	Threshold Accuracy Voltage Test Settings
	Threshold voltage setting	DC offset voltage setting	Limits
	(in oscilloscpe User softkey)	(on oscilloscope calibrator)
	+5.00 V	+5.250 V ±1 mV dc	Lower limit = +4.750 V
			Upper limit = +5.250 V
	–5.00 V	–4.750 V ±1 mV dc	Lower limit = –5.250 V
			Upper limit = –4.750 V
	0.00 V	+100m V ±1 mV dc	Upper limt = +100 mV
			Lower limit = –100 mV

8Do the following steps for each of the threshold voltage levels shown in Table 3-3.

a Set the threshold voltage shown in the User softkey using the Entry knob on the oscilloscope.

b Enter the corresponding DC offset voltage on the oscilloscope calibrator front panel. Then use the multimeter to verify the voltage.

Digital channel activity indicators are displayed on the status line at the top of the oscilloscope display. The activity indicators for D7-D0 should show all of the channels at digital high levels.

cUse the knob on the oscilloscope calibrator to decrease the offset voltage, in increments of 10 mV, until the activity indicators for digital channels

D7-D0 are all at digital low levels. Record the oscilloscope calibrator voltage in the performance test record.

dUse the knob on the oscilloscope calibrator to increase the offset voltage, in increments of 10 mV, until the activity indicators for digital channels D7-D0 are all at digital high levels. Record the oscilloscope calibrator voltage in the performance test record.

Before proceeding to the next step, make sure that you have recorded the oscilloscope calibrator voltage levels for each of the threshold settings shown in Table 3-3.

9Use the 8-by-2 test connector or the Agilent 01660-63801 Test Fixture to connect digital channels D15-D8 to the output of the oscilloscope calibrator. Then connect the D15-D8 ground lead to the ground side of the 8-by-2 connector.

10Repeat this procedure for digital channels D15-D8 to verify threshold accuracy and record the threshold levels in the Performance Test Record.

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