LeCroy DA18000, Instruction Manual

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Performance Verification
DA18000-OM-E Rev A
7-5
l. Record the measured 20-80% rise time as “Source rise time” (t
source
) in the Test
Record (Figure 7-4).
Only the positive edge is measured. The difference in rise time between the positive
edge and the negative edge of the STD-20 TDR is less than 1 ps.
m. To measure the amplifier’s rise time, disconnect the coaxial cable and PLPA-K adapter
from Channel 1 of the SDA 18000 and connect the cable only to the + input of the
DA18000 amplifier. Connect the cable from Channel 2 TDR to the – input of the ampli-
fier.
n. Measure the 20-80% rise time and record the measurement as “System rise time”
(t
system
) in the Test Record.
o. Calculate the amplifier’s rise time:
Figure 7-4. Rise Time Measurement
p. Record the calculated rise time as “Amplifier Rise Time” in the Test Record.
q. Verify that the calculated rise time for the DA18000 is less than 19 ps.
This concludes the Performance Verification Procedure.
2. Voltage Gain Accuracy
a. Set the scope Aux output equal to a 50 Hz, 250 mV.
b. Connect the Aux output to a scope channel through an adapter that allows the voltage
to be simultaneously measured with a DMM.
Amplifier Rise Time, t
r
t
system
( )
2
t
source
( )
2
– =