Switch card

This is not usually specified for a switch card, but the limitation is usually a function of the trace width and connector ratings .

End-of-life is generally considered to be the time when the total channel resistance exceeds the specifications for the switch card.

The contact resistance is the resistance across a closed pair of contacts on a switch card.

To measure the offset of a switch card, connect the output of the card to a pico ammeter or electrometer.

The contact potential or thermoelectric offset voltage is the key specification of a switch card designed for low voltage switching.

Contact potential is affected by changes in ambient temperature as well as by the presence of temperature gradients across a switch card.

Information about making connections to a particular switch card can be found in the card's manual.

However, this method is the least expensive because a general-purpose switch card or module can be used.

This may require using a high current switch card for sourcing and a low voltage switch card for measuring.

Even if all this is done to the switch card, external connectors and cables can still degrade performance.

The offset current specification of the switch card should be as low as possible for switching low current.

This section describes microwave switch types, RF switch card specifications, and RF switch design considerations.

Factors that affect the maximum current through the switch card include the traces on the board, the connectors, and the relays.

Switch card specifications are usually stated with a specific application in mind, such as low current or high voltage switching.

Furthermore, system hardware design contains the design of power card, vector driver card, and channel switch card.

Handle the switch card by the edges to avoid contaminating it with dirt, body oil, etc.

Then connect the voltmeter to the HI and LO output terminals of the switch card.

To prevent leakage current on the switch card, take special care when handling to prevent degradation of performance.

To avoid switch card damage, be particularly careful when switching voltages of ~200V or higher.

The connections to the switch card itself represent another source of thermally generated voltages.

power is routed to the handsets by the Model 7053 High Current Switch Card.

To ensure proper shielding, choose a switch card with shielded connectors, such as coax or triax connectors.

It can be found on the switch card, in the connecting cables, and in the test fixture.

Refer to the instruction manual for the switch card for isolation measurement procedures specific to that card;

Industry: Group Phone; Switch; Card; Communication cable; Communications equipment agent; IP telephone;