Model 8010 High Power Device Test Fixture User's Manual
Section 6: On-state characterization of a power MOSFET
8010-900-01 Rev. C / March 2017
6-11
smua.source.offmode = smua.OUTPUT_NORMAL
smua.source.offfunc = smua.OUTPUT_DCVOLTS
smua.source.offlimiti = 1e-3 -- Set off limit
-- SMU #1 will be a 0 V voltage source with 1mA limit when its
-- output is turned off. SMU #2 will be a 0 A current source with
-- a 10 V limit when the output is turned off. These settings keep
-- the parallel combination safe in case one SMU is turned off.
smua.source.rangei = math.max(math.abs(dstart / 2), math.abs(dstop / 2))
smua.source.leveli = 0 -- Sets the DC bias level
smua.source.limitv = 9 -- Sets the DC bias limit
-- SMU #2 will have a voltage limit of 10V. By setting the voltage
-- limit 10% lower than that of SMU #2, we can ensure that only
-- one of the two SMUs will ever go into compliance and become a
-- voltage source. This is desirable, because if both SMUs went
-- into compliance, there would be two voltage sources in parallel,
-- which is an unsafe condition.
smua.measure.nplc = 0.005
smua.measure.rangev = pulseLimit
smua.measure.autozero = smua.AUTOZERO_ONCE
smua.measure.delay =
pulseWidth - ((1 / localnode.linefreq) * smua.measure.nplc)) - 20e-6
-- Set the delay so that the measurement is near the end of the pulse
-- Prepare the reading buffers
smua.nvbuffer1.clear()
smua.nvbuffer1.collecttimestamps = 1
smua.nvbuffer1.collectsourcevalues = 1
smua.nvbuffer1.fillmode = smua.FILL_ONCE
smua.nvbuffer2.clear()
smua.nvbuffer2.collecttimestamps = 1
smua.nvbuffer2.collectsourcevalues = 1
smua.nvbuffer2.fillmode = smua.FILL_ONCE
-- Configure TSP-Link Trigger 1
tsplink.trigger[1].clear()
tsplink.trigger[1].mode = tsplink.TRIG_FALLING
tsplink.trigger[1].stimulus = trigger.timer[1].EVENT_ID
-- TSP-Link Trigger 1 signals 2651 #2 to pulse
-- Timer 1 controls the pulse period by triggering the pulse to begin
trigger.timer[1].count = dsteps - 1
trigger.timer[1].delay = pulsePeriod
trigger.timer[1].passthrough = true
trigger.timer[1].stimulus = smua.trigger.ARMED_EVENT_ID
trigger.timer[1].clear()
-- Timer 2 controls the pulse width
trigger.timer[2].count = 1
trigger.timer[2].delay = pulseWidth - 3e-6
trigger.timer[2].passthrough = false
trigger.timer[2].stimulus = smua.trigger.SOURCE_COMPLETE_EVENT_ID
trigger.timer[2].clear()