USB Power Delivery Test Equipment
The USB-PDT is a Power
Delivery Compliance tester. It is pictured here fitted
with the PDT-BT2-CON1 plug-in for testing on C-Type
connector equipped Units Under Test
In this form it is
capable of performing the complete suite of USB-IF
Power Delivery Compliance Tests for both Cable E-Marker
and PD Devices.
The USB-PDT is intended
for use by compliance test houses and USB-IF workshops,
and will also be found to be of great value to developers
of Power Delivery Devices and E-markers, as it can
save its cost many times over in potential failure
of compliance testing done for the purpose of certification.
The USB-PDT Tester
is equipped with the following resources:
Test Suite runs automatically
with minimal intervention
A device with no issues can
typically be tested in around 10 minutes
BMC Transmitter and Receiver
employing 250Ms/s digital signal processing
Capability of Displaying BMC
signal Eye Diagram with approximately 15 bit resolution
Capability of generating signal
distortions for running the specified Interference
Rejection tests required.
100W PD VBUS Generator, automatically
controlled by the tester
100W PD VBUS Load, automatically
controlled by the tester
VBUS Voltage and Current Measurement.
Voltages are effectively made at the UUT end of
the calibrated test cable supplied
A comprehensive Power Delivery
Engine to allow the tester to behave as any knind
of appropriate Port Partner during testing, and
also to apply unusual test conditions to the Unit
Automatic Analyser Capture During
External Power Supply Provided
An Exerciser capablity is currently
The digital signal
processing nature of the USB-PDT receiver allows it
to display an eye diagram plotted using the exact
algorithm specified in the USB PD Compliance Plan.
Around 15-bit resolution ensures an accurate and clean
eye diagram; very important during compliance.
During testing, the
entire sequence of PD messages is captured and displayed.
Each event is analysed in the Details pane. Every
bit field is analysed, described and any potential
non-compliances are highlighted.SOP', SOP'', SOP'_debug
and SOP''_debug messages are also displayed. The locations
of the packets and the scope captures, together with
voltage and current, are shown in the zoomable timeline.
VBUS scope captures
are made at appropriate points in the testing, and
these can be displayed, along with the related message
positions. Each scope capture has a mask added to
illustrate the adherence or otherwise of the waveforms
to the specification.
Plug-ins for Packet-Master
The USB-PDT uses a
plug-in module to allow simpler hardware upgrades.
The current version of the plug-in is the PDT-BT3,
which was specially designed to meet the test requirements
of the PD Specification Rev 3 compliance test.
The C-Type connector
is mounted on a mini-board to make it user-replaceable.
This is a huge advantage if the connector becomes
worn or damaged.
Extended Power Range Provision
The USB-PDT has now been
replaced by the PDT-EPR (the USB-PDT is now longer available).
PDT-EPR v Original USB-PDT
Reason for New Design
The USB-IF has introduced
new requirements in the Power Delivery Specification,
which involve higher voltages and power levels in a
PD product. Consequently they also require that Testers
for such products should be able to cover these new
Detail of Changes Required
Essentially a Tester is now required to provide voltages
of up to 48V, instead of the previous 20V, and load
testing is required to sink 240W instead of the previous
100W. This has required a re-design of the USB-PDT,
involving three new PCBs, a new higher powered external
power supply, a new higher voltage Test Cable, and more
efficient cooling arrangements.
It is now necessary to use a
Tester with the higher capability, in order to be able
to satisfy Compliance Requirements.
Even UUTs not implementing the higher voltages need
to be tested with the new Tester Specification.
PDT-EPR v USB-PDT Comparison Table
|VBUS Generator Voltage Range
|VBUS Settable Current Limit
||Tester as PPS Source
||0 5A 100W
||0 5A 240W
||EPR and SPR
|VBUS Voltage Measurement Range
||Custom 20V/5A Cable
||Custom 50V/5A Cable
|External Power Supply
We have arranged that the new capabilities can be accommodated
in the existing box size, to allow the possibility of
upgrading existing units. The following table describes
the possible upgrade paths.
||Complete Power Delivery
Compliance Tester with support for EPR, including
BT3 and permanent registration for CTS software.
||Upgrade of existing
USB-PDT to support EPR, including permanent registration
for CTS software. Does not include BT3.
||Upgrade of existing
USB-PDT to support EPR, for customers who already
have permanent registration for CTS software. Does
not include BT3.
Comparison Sheet (PDT-EPR v PDT)