Texas TSW1100, Быстрый старт

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4.1 Information
4.2 Setting up Remote Control of Instruments
4.3 Select the ADC Under Evaluation
4.4 Configure the Input Waveform (A
IN
) Conditions
4.5 Configure the ADC Sampling Frequency (Fs) conditions
4.6 Configure the TSW1100 Capture
Chapter 4
SLAU155 – August 2005
Performing a Dual Channel Capture
This section allows you to perform a dual-channel capture from a dual channel ADC, perform an FFT, plot
the results and display the performance of the ADC under evaluation.
For the best performance Texas Instruments recommends using an Agilent 8644 for both the signal
source and the clock source with the appropriate filters. The TSW1100 software automatically controls
these instruments if they hooked up using GPIB and the Remote Control of Lab Instruments is turned on
in the Equipment Setup tab. You may also change the GPIB address for both the signal generator and
clock generator.
In the top left-hand corner of the user controls, find the pulldown control labeled Texas Instruments Chip.
Select the appropriate EVM from the list. Based off this selection, the software will automatically update
the ADC characteristic indicators: Number of Bits and 2's Compliment.
Find the control labeled Desired Frequency and change it to the sinusoidal frequency you would like to
provide to the ADC analog input. In it's default state and for the best ADC performance, the software
calculates a coherent bin based off of a prime integer and it displays it in the Frequency indicator. If you
are not using the Remote Control of Lab Instruments feature, then manually set your signal source output
frequency to coincide with the displayed Frequency indicator. You also have control over the amplitude of
the signal source. Texas Instruments recommends that you set this to be -1 dBFS of the device under
evaluation.
Find the control labeled Sampling Frequency and set this to the value at which you want to clock the ADC.
For the best performance, do not set this above the recommended device operating frequency. Set the
clock amplitude by varying the clock amplitude control.
Use the Capture control to select which Chan 1 + Chan 2. Select the depth of capture by selecting the
acquisition size in the Number of Points control. Texas Instruments recommends that you set this to
16384 for sinusoidal input evaluation.
SLAU155 – August 2005 Performing a Dual Channel Capture 11