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FAST TRANSITION-TIME
MODULES
OPTION 04A: 100 ps RISETIME
OPTION 04B: 100 ps FALLTIME
OPTION 04C: BIAS TEE
INTRODUCTION
Available as options for the Digital Delay /
Pulse Generator, these modules will enhance the
leading or trailing edge pulse transition times by
a factor of 20. Applications include time domain
reflectometry measurements, recording the pulse
response of fast amplifiers, checking high speed
digital circuits or use as a low jitter trigger
source in high EMI environments.
The devices consist of a step recovery diode and
matching network mounted in an in-line package
with BNC type connectors. The units provide a fast,
low distortion step into a 50
Ω
line with adjustable
amplitudes from 0.5 V to 2.0 V. There is a fixed
negative offset of -0.8 VDC for the fast risetime
model, and +0.8 VDC for the fast falltime model.
These units can provide step amplitudes of up to 3.7
V with some increase in distortion, and up to 15 V
when used with option 02 (rear panel outputs) and
option 04C (bias tee).
OPERATION
For step amplitudes of less than 3.7 V the fast
transition time units should be attached directly to
the front panel of the DG535.
SPECIFICATIONS
When used on front panel with 50
Ω
load.
OPTION 04A: FAST RISETIME
OPTION 04B: FAST FALLTIME
Output Amplitude1
0.5 to 2.0 VDC
Output Amplitude1
-0.5 to -2.0 VDC
Output Offset
-.8 VDC, typ.
Output Offset
+0.8 VDC, typ.
Transition Time
Transition Time
Rise (20/80%)
100 ps, max.
Rise (20/80%)
2500 ps, max.
Fall (20/80%)
2000 ps, max.
Fall (20/80%)
100 ps, max.
Pulse Aberrations
Pulse Aberrations
Foot
4%, typ.
Foot
4%, typ.
Ring
±5%, typ.
Ring
±5%, typ.
Warranty: One year parts and labor on materials and workmanship.
Note1: Amplitudes up to 3.7 Volts are obtainable with some increase in distortion. Amplitudes up to 15 Volts are
available using DG535 option 02, rear panel ouputs and option 04C, bias tee.
