Tektronix TDS 420A, Service Manual, Page: 30 / 288

Nominal Traits
1- 8
TDS 420A, TDS 430A & TDS 460A Service Manual
Table 1- 3: Nominal Traits — Signal Acquisition System (Cont.)
Name Description
Rise Time
4
Volts/Div Setting Rise Time
(TDS420A)
5 mV/div--10 V/div 1.75 ns
2 mV/div--4.98 mV/div 2.33 ns
1 mV/div--1.99 mV/div 3.68 ns
Rise Time
4
Volts/Div Setting Rise Time
(TDS 430A and TDS 460A)
5 mV/div--10 V/div 875 ps
2 mV/div--4.98 mV/div 1.4 ns
1 mV/div--1.99 mV/div 3.5 ns
1
Displayed vertically with 25 digitization levels (DLs) per division and 10.24 divisions dynamic range with zoom off. A DL
is the smallest voltage level change resolved by the 8-bit A-D Converter with the input scaled to the volts/division setting
of the channel used. Expressed as a voltage, a DL is equal to 1/25 of a division times the volts/division setting.
2
GND input coupling disconnects the input connector from the attenuator and connects a ground reference to the input of
the attenuator.
3
The sensitivity ranges from 1 mV/div to 10 V/div in a 1 - 2 - 5 sequence of coarse settings. Between consecutive
coarse settings, the sensitivity can be finely adjusted with a resolution of 1% of the more sensitive setting. For
example, between 50 mV/div and 100 mV/div, the volts/division can be set with 0.5 mV resolution.
4
Rise time is defined by the following formula:
Rise Time
(
ns
)
=
420
BW
(
MHz
)