Sifos Technologies PowerSync PSA100, Technical Reference Manual, Page: 14 / 147

PowerSync Analyzer Reference Manual
March 9, 2010 Sifos Technologies page 14
2.3. System Hardware Overview
The diagram below shows a block diagram of a single PowerSync Analyzer (PSA) test port. Each PSA test blade (or
PSA100 instrument) contains two of these measurement circuits, which are electrically isolated from each other and
from the chassis control circuitry.
The PSE input connector is connected to a PSE device under test. The DC power and related common mode control
and classification signals are tapped off and fed to the measurement subsystems. The DC voltage and very low
frequency, common mode PoE signals are not visible at the output port. The data signal is passed directly to the output
connector, and can be used for data-related measurements with other test equipment.
At the front end of the test port, there are two sets of switches. These are implemented with electro-mechanical relays.
The ALT-A/B switch selects which wire pair is connected to the PSA test resources. The Polarity switch selects the
polarity of the power supplied by the device under test. ALT-A/B and Polarity settings will depend upon the
characteristics of the equipment being tested. Incorrect settings of either switch will not damage the instrument.
The paragraphs that follow will cover each test subsystem in greater detail.
2.3.1. Port Switch and Detection Subsystem
The Port Switch and Detection Passives subsystem provides the detection loading required for a PSE under test to
recognize a Powered Device (PD) “signature” so that it can turn on and supply power. It also provides an AC Maintain
Power Signature (MPS) resistive loading that is visible to a powered-up PSE. This load value is at the top of the range
where PSE’s must interpret a valid load signature.
The Port switch is used to connect the passive detection loads to the PSE under test. On initial power-up of the PSA-
1200, this switch is typically in the open (or “isolated”) position. This switch closes and opens under software control,
and within all PowerSync Analyzers
excluding
the PSA-PL, may be used as a triggering event for many single-shot
measurements of detection and MPS behaviors.
The Detection Passives are affected by an internal disconnect feature that is dependent only upon the PSE voltage level.
When the PSE voltage reaches approximately 11 volts, the passive R-C Detection signature is removed and the MPS
signature R-C circuit is inserted thus presenting a valid AC MPS signature following PSE power-up for as long as the
Port Switch is closed (or connected).
PSA1200 Test Port Resources
PSE IN DATA Out
Resistance
9 – 39 K
Ω
Capacitance
.1, 4.8, 6.9,
11.6, 47*, 52*,
54*, 58* uF
AC MPS R
24 K
Ω,
11 V
Activation
Port
Switch
Trig1, Trig2
•
Rising
•
Falling
•
0 – 64 V
•
.25V Res.
Static Load
•
0 – 510 mA,
•
0.5 mA Res.
•
15V Activate
2-Step Trans.
•
200 msec –
1 sec/step
•
0 – 510 mA
•
Opt. 2
nd
step
“hold”
•
Triggers
Volt & Current
•
Average
•
Min. Peak
•
Max. Peak
•
Trace
Meas. Period
•
10msec–10sec
Triggers
•
Immediate
•
Trig1
•
Ext. Trigger
Low Band
•
16Hz – 5KHz
•
4Vpp full scale
•
10msec – 5sec
High Band
•
5KHz – 300KHz
•
1Vpp full scale
•
10msec – 5 sec
Meas. Period
•
10msec – 5sec
Load
Current
*
“Type 2” or “Type 3” PSA Test Blades Only
ALT A/B Select
Polarity Select
Detection and
MPS Passives
Triggers Active Load DC Meters TI Meter AC P-P Meter
Time Interval
•
20
μ
sec – 6.5
sec range
•
1 msec or
1
μ
sec Res.
Start Trigger
•
Trig1
•
External
Stop Trigger
•
Trig2
PSA1200 Test Port Resources
PSE IN DATA Out
Resistance
9 – 39 K
Ω
Capacitance
.1, 4.8, 6.9,
11.6, 47*, 52*,
54*, 58* uF
AC MPS R
24 K
Ω,
11 V
Activation
Port
Switch
Trig1, Trig2
•
Rising
•
Falling
•
0 – 64 V
•
.25V Res.
Static Load
•
0 – 510 mA,
•
0.5 mA Res.
•
15V Activate
2-Step Trans.
•
200 msec –
1 sec/step
•
0 – 510 mA
•
Opt. 2
nd
step
“hold”
•
Triggers
Volt & Current
•
Average
•
Min. Peak
•
Max. Peak
•
Trace
Meas. Period
•
10msec–10sec
Triggers
•
Immediate
•
Trig1
•
Ext. Trigger
Low Band
•
16Hz – 5KHz
•
4Vpp full scale
•
10msec – 5sec
High Band
•
5KHz – 300KHz
•
1Vpp full scale
•
10msec – 5 sec
Meas. Period
•
10msec – 5sec
Load
Current
*
“Type 2” or “Type 3” PSA Test Blades Only
ALT A/B Select
Polarity Select
Detection and
MPS Passives
Triggers Active Load DC Meters TI Meter AC P-P Meter
Time Interval
•
20
μ
sec – 6.5
sec range
•
1 msec or
1
μ
sec Res.
Start Trigger
•
Trig1
•
External
Stop Trigger
•
Trig2
Figure 2.6
PSA Test Port Resources