• Differential (A–B)
• A input (single-ended to ground)
• B input (single-ended to ground)
• Common-mode ((A+B)/2 to ground)
The probe input mode can also be selected using the oscilloscope Probe Setup configuration menu. The Probe Setup
configuration menu is also used to adjust the probe Differential offset, Common mode offset, A side offset and, B side offset
voltage settings. All other TDP7700 Series probe internal controls, such as vertical scaling, are handled automatically
through communication between the probe and oscilloscope.
CAUTION: To prevent damage to the probe, use care when handling the probe. Rough or careless use can
damage the probe.
LED indicators
There is a Status indicator LED located on the top plate of the probe comp box. This LED is normally green, but turns red
when any of the following conditions exist and remains red until the problem condition is cleared:
• Probe power-on self-test failure (clear by disconnecting and reconnecting the probe)
• Probe over-temperature detected (clear by disconnecting and reconnecting the probe, allowing time for probe to cool)
• Probe input over-voltage detected (reduce input over-voltage to clear)
• Probe over current detected (adjust V
term
or remove input signal to clear)
If the LED is red, disconnect and reconnect the probe to restart the power-on diagnostic sequence. If the symptoms
continue, connect the probe to another oscilloscope channel or oscilloscope. If the symptoms remain, return the probe to
Tektronix for repair.
Main interconnect cable
This cable assembly consists of a pair of matched, low-loss coaxial signal cables that carry the acquired signal from the
probe head to the probe comp box. The cable assembly includes an 8-conductor bundle of wires that supply probe tip head
power and control signals from the probe comp box through the TekFlex connector interface. Some of the wires carry
bidirectional data, such as queries and responses about the type of probe tip attached to the TekFlex connector, and other
probe tip-specific information.
TekFlex™ connector
The new TekFlex connector technology combines a high speed signal path with low speed control signaling in a single, easy
to connect accessory connector. The TekFlex connector has a pinch-to-open design that when open requires minimal force
to attach an accessory tip. When the TekFlex connector is closed, it provides a secure connection to the accessory to avoid
accidental disconnections.
The connector provides a light-weight electrical and mechanical interface between a TDP7700 Series probe and a TekFlex
active probe tip. It contains a spring-loaded set of electrical contacts that connect between the main cable wiring and
contact patterns on the attached probe tip. There is a differential, high-frequency contact pattern on the top of the probe tip
that connects the probe tip dual signal inputs and grounds to the probe main cable coaxial pair. There is also an eight-finger
contact pattern on the bottom of the probe tip that connects the probe tip power and control signals to a ribbon wire in the
main cable. The TekFlex connector provides mechanical alignment between a keyed hole pattern on the probe tip and a pair
of pins inside the spring loaded connector housing.
With the TekFlex connector, the TDP7700 series probes offer a set of active probe tips with the probe's buffer amplifier only
millimeters from the input connections. The short signal path enabled with the active tips provides high fidelity and a high
impedance input. It minimizes signal loss, capacitance, and additive noise.
Probe tips
The probe tips are automatically detected and displayed in the Probe Setup configuration menu.
Theory of operation
TDP7700 Series TriMode™ Probes Technical Reference
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