Sifos Technologies PowerSync PSA100, Technical Reference Manual, Page: 125 / 147

PowerSync Analyzer Reference Manual
March 9, 2010 Sifos Technologies page 125
8.1.3. Time-Interlacing of Tests Across Ports
Test scripts written for the PowerSync Analyzer can readily take advantage of the measurement “state machine”
behavior of each test port as described earlier in Section 3.1.9 (Triggered Measurements). Two factors that routinely
affect measurement times during testing on a specific test port are:
•
Time for PSE to produce the signal or behavior of interest
•
Measurement time (or aperture) for the measurement to complete
The concept of time-interlacing tests across ports essentially
means that while one or more ports are waiting for triggering
events and/or completing measurements, other ports can be
configured for similar or different measurements.
There are numerous ways to apply this concept in the development
of a high speed test script, so this section will provide just a couple
of examples to demonstrate the concept and quantify the test speed
improvements. Note that the examples in this section will also
take advantage of the concepts of rapid port replication and
customizing test methods described in the previous sections.
In the first example, a script is developed to recover three
parameters from each of six test ports. These parameters are:
•
Vvalid(Max)
Peak detection voltage
•
Vport
Powered-up port voltage
•
Rgood(Max)
Validate a maximum signature threshold
One power-up per test port (or PSE port) is all that is required to recover all three parameters. Our test script,
psa_take_six
will accept six user-supplied test ports to be tested. The Vvalid(Max) measurement will be configured
and initiated on each port before it is completed on any ports. Vport will then be measured immediately following the
port power up given the detection load of Rgood(Max). If Vport shows the port not to be powered (i.e. < 44 V), then
Rgood(Max) will be inferred to be below the target value (28 K
Ω
) used in the test script.
# Initialize port to 15.1 Watts power
set Vport [lindex [ power_port 1,1 p 15.1] 1]
if { $Vport < 44 } {
puts "Port Power Capacity is below 15.1 Watts"
}
foreach power "15.4 15.7" {
# Calculate target current level
set current [expr round(1000.0 * $power / $Vport)]
# Establish the power level by increasing the current
iload 1,1 i $current
# Wait .5 seconds and assess port status, use pstatus command for speed
after 500
set status [lindex [
pstatus 1,1 stat] 3]
# If power is off, exit loop with pMax = previous power tested
if { $status == "OFF" } {
set pMax [expr $power - .3]
break
}
}
puts "Power_Capacity= $pMax Watts"
Pre-Configure
Port
Use Port Replication
Configure
Measurement
Use Port Replication
Sync Up ? Port N
Initiate Triggered
Measurement
Port N
Result
Ready
Configure Port Port N
Dead Time
Opportunity
To Sync, Configure,
And Initiate Triggered
Measurements on Other
Ports
Pre-Configure
Port
Use Port Replication
Configure
Measurement
Use Port Replication
Sync Up ? Port N
Initiate Triggered
Measurement
Port N
Result
Ready
Configure Port Port N
Dead Time
Opportunity
To Sync, Configure,
And Initiate Triggered
Measurements on Other
Ports
Figure 8.6
Multi-Port Command Interlacing