THS3215 Datasheet, PDF (24/71 Pages) Texas Instruments – THS3215 650-MHz, Differential to Single-Ended DAC Output Amplifier

THS3215
SBOS780A – MARCH 2016 – REVISED APRIL 2016
www.ti.com
8.3 Harmonic Distortion Measurement
The distortion plots for all stages used a filtered high-frequency function generator to generate a very low-
distortion input signal. The LMH3401 interface was used when testing the D2S and the full-signal path (D2S +
OPS) harmonic distortion performance. Running the filtered signal through the LMH3401, as shown in Figure 70,
provided adequate input signal purity because of the approximately –100-dBc harmonic distortion performance
through 100 MHz provided by the LMH3401. In order to test the harmonic-distortion performance of the OPS and
midscale buffer, the configuration shown in Figure 71 was used.
Function
Generator
- ^<>
Output
50
Low-Pass Filter
LMH3401EVM
+_
±⁺
THS3215EVM
IN+ ₊
±
IN-
I Input
Q Input
Ext Trig
Spectrum
Analyzer
RF
Input
50
High-Pass Filter
20-dB
Attenuator
Figure 70. Harmonic-Distortion Measurement: D2S and Full-Path (D2S + OPS) Circuit Configurations
Function
Generator
- ^<>
Output
50
Low-Pass Filter
THS3215EVM
+
±
I Input
Q Input
Spectrum
Analyzer
Ext Trig
RF
Input
50
High-Pass Filter
20-dB
Attenuator
Figure 71. Harmonic-Distortion Measurement: OPS Inverting and Noninverting and Midscale Buffer
Circuit Configurations
24
Submit Documentation Feedback
Product Folder Links: THS3215
Copyright © 2016, Texas Instruments Incorporated