Datasheet

Datasheet
CT1/CT2. Current Probes with P6041 BNC Probe Cable.
Miniature Construction
The C T1 and CT2 detachable cable design e
nables one or more probes to
be locat ed on circuit boards or in other limited space areas.
The CT6 offers the smallest form factor available, for measureme nt on
ever-shrinking circuit boards and components. It is designed f or temporary
installation and does not incorporate removable cables, as the CT1 and
CT2 do.
Extendible Probe Length
Specified rise time and bandwidth are obtained when using the probe
cables provided: The P6041 cable used with the CT1 and CT2 is 42 inches
nominal. If additional length is required, the cables can be extended by
using high-quality 50 Ω cable an d suitable interface connectors. (Also see
Special Probe Cables, Optional Accessories.) Long cables may degrade
high-frequency response.
High Sensitivity
The CT1 and CT6 provide an output of 5 mV for each milliamp of input
current when terminated in 50 Ω. The CT2 provides 1 mV per milliamp when
terminated in 50 Ω.
Typical Systems
The CT1, CT2, and CT6 high-frequency current transformers are dynamic
(i.e., non-DC) curre nt measuring devices. They are typically used in
conjunction with compatible high-bandwidth oscilloscopes and other
instruments to observe and/or re cord high-frequency current waveforms.
The CT1, CT2, an
d CT6 normally operate directly into 50 Ω scopes and
other measuring device inputs.
The CT1 or CT2 ca
nbeusedwith1MΩ input systems; use the P6041
probe cable and terminate the output with a 50 Ω feed-through termination
(see Optional Accessories).
In all cases, the CT1, CT2, and CT6 must work into 50 Ωs to obtain
specified performance and sensitivity.
Typical Measu
rement Applications
Differentia
l Current Measurements
Most true-differential voltage amplifiers have a maximum bandwidth
of about 100 M
Hz. The CT1 or CT6 can make differential current
measurements to 1 GHz and 2 GHz, respectively, by passing two w ires
carrying opposing currents through the same core. The displayed result is
the difference current. The CT2 can perform the same function to 200 MHz.
In all cases, Derating with Frequency and Amp-second Product
(Current-time Product) g uidelines should n ot be exceeded. (See
Characteristics.)
Single-shot and Low Rep-rate Pulse Measurements
These common measurements are easy to make with the CT1, CT2, or CT6
provided that your signal fits within the Max Pulse C urrent and Amp-second
Product (Current-time Product) guidelines for the sp ecific current probe
characteri
stics.
For example, the CT2 is rated at 36 A peak, with an Amp-second Product
of 50 × 10
-6
s
econds (50 Amp-microseconds), therefore the CT2 can safely
handle a 36 A peak pulse with a maxim um width of 1.39 microseconds or
lower amplitude pulses for longer pulse widths. The CT1, CT2, and CT6
all have low-frequency roll-off characteristics. Low-frequency "droop" w ill
exhibit itself when the pulse width approaches the L/R time constant of the
specific transformer.
Propagation Delay Measurements
Two CT1 or CT2 C urrent Transformers with m atching probe cables can
be used to measure propagation delay (transit time) between the input
and outpu
t currents of high-frequency devices. The probe outputs are
connected to the inputs of dual-channel real-time or sampling scopes.
Verificat
ion of any Probe/Cable/Scope System mismatch can be obtained
by passing the same signal current through both probes and observing total
system delay difference, if any.
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