Operating Basics Table of Measurements and Options
Area
Option
Description
Signal Qualit
y C heck
Signal Rate Measures the i
nverse of the average bit-time that
gives the transmission rate of the Test_Packet
Signal Quality Check
Monotonic Pro
perty
Detects when the Signal is Monotonic i f and only
if data [i+1] ≥ data [i] in case of consistently
increasing (
rising slope), never decreasing data
[i+1] ≤ data [i] when consistently decreasing
(falling slope) and never increasing in value where
i ranges fro
m0ton
Signal Qual
ity Check
EOP Width Measures th
e width of the end-of-packet pattern of
a Test_Packet
Signal Quality Check
Rising Edg
eRate
Measures the Rising Edge/Slew rate in V/ μs and
is calculated using the Rise time as
Rising Ed
ge Rate = Amplitude / R ise Time
Where Amplitude is the peak-to-peak amplitude for
the corresponding signaling rate and the Rise time
is calcul
ated based on the high level of the inner
vertical eye height reference levels
Signal Quality Check
Falling
Edge Rate
Measures the Falling Edge/Slew rate in V/ μs and
is calculated using the Fall time as
Fallin
g Edge Rate = Amplitude / Fall Time
Where Amplitude is the peak-to-peak amplitude for
the corresponding signaling rate and the Fall time
is calc
ulated based on the lower level of the inner
vertical eye height reference levels
Inrush Current Check Inrush Current Measures the amount of electrical charge drawn
by a device as s oon as it is connected to a USB
netwo
rk
Droop Test Droop Test
Meas
ures the difference in the VBUS voltage when
the load switch is open to the lowest value of the
voltage and the load switch
Receiver Sensitivity Test Receiver Sensitivity Is an indicator o f Receiver Sensitivity. A High
Spe
ed capable device must indicate ’packet(Data)
not received’ (squelch) w hen the input of the
receiver falls below 100 mV differential amplitude.
Si
milarly the device must not indicate squelch if the
differential amplitude is greater than 150 mV
Chirp Test Chirp Checks a part of handshake that occurs during
Reset Protocol for high speed capable hubs and
d
evices. In this handshake, the hub/host and the
device are required to detect chirp J and K of a
specified minimum duration and amplitude
Suspend Test Suspend Measures the time between the end of the last
Start o f Frame (SO F) and the rising edge transition
to the Full Speed J state. The acceptable range
should be between 3 m s to 3.125 ms. This is
applicable if you have selected a Host, Device, or
a Hub-Upstream device
TDSUSB2 Universal Serial Bus Measurements Package 29
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