Design World – Power Transmission Reference Guide June 2019

eeworldonline.com | designworldonline.com 6 • 2019 DESIGN WORLD — EE NETWORK 39

Tektronix AWG5200

https://www.tek.com/arbitrary-waveform-generator/awg5200

After importing a data sequence, the pattern generation tool

allows for receiver margin testing. Before compiling the waveform,

users first select the desired data-rates for margin testing. By

selecting a low and high data rate, and by specifying the step

increment, the software creates a sequence of waveforms that run

the digital pattern through a stepped range of data rates.

Alternatively, margin testing with skew, jitter, amplitude, and

offset adjustments can be realized with individual signal parameter

selections. It’s also possible to adjust the amplitude, as well as add

skew and periodic jitter. Offset can be adjusted in the AWG after

signals are assigned to a given output.

PUSH THE LIMITS

Despite the emergence of wireless and fiber optic transmissions,

plenty of data transmissions still go through good old-fashioned

copper using LVDS signaling. With its combination of high

performance, low power consumption and immunity to EMI, LVDS

continues to serve in wide range of high-performance applications.

True margin and stress testing of LVDS devices involves the use

of complex waveforms such as bio signals for medical applications,

automotive test bus signal simulations and telecommunications

network testing as well as the need to add a range of impairments.

The recent availability of high-channel count AWGs coupled with

pattern generation software significantly simplifies the task of

thoroughly testing LVDS devices.

For LVDS environmental testing, an

AWG such as the Tektronix AWG5200

generates a known clean signal that

is sent to DUT and evaluated by an

oscilloscope under varying conditions.

TESTING LVDS

Temperature chamber

DUT

Generate known,

clean signal

8-channel AWG

8-channel oscilloscope

Typical LVDS test setup

Tektronix — Test and Measurement HB 06-19.indd 39 6/10/19 8:32 AM