Frequently Asked Questions (FAQ)
for RF Switches |
1) What does the terminology “reflective”, “absorptive”, “self-terminating” mean? |
Reflective switch: Switch ports are high impedance (open) when turned off.
Absorptive switch: Switch ports are 50 Ohm when turned off.
Self-terminating switch: Switch ports are 50 Ohm when turned off.
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| 2) What does the terminology “N.O.” and “failsafe” mean? |
Normally Open (N.O.) switch: With no power applied, common port is connected to none of the output ports.
Failsafe switch: With no power applied, common port is connected to one of the output ports.
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| 3) What does the terminology “cold switch” and “hot switch” mean? |
Cold switch: No signal is applied to the switch while the switch is changing states.
Hot switch: The switch changes states while a signal is still being applied to the switch.
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| 4) What are the pro's and con's of solid-state versus relay RF switches? |
| Solid-State Pros | Relay Pros | | Typical MTBF = 250,000 hours | Wide frequency range (works at DC) | | Excellent insertion loss repeatability | Higher input power | | Switching speed (microseconds) | Low harmonic distortion | | Solid-State Cons | Relay Cons | | Increased harmonic distortion | Switching speed (milliseconds) | | Lower input power * | lifetime (1 million operation typical) | | *Solid-state switches will typically handle much less power than relay models. However, JFW has a line of high power solid-state switches that can hot switch up to 100 Watts and cold switch up to 250 Watts, depending on the model. |
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| 5) Are the RF switches attenuators bi-directional? |
All of JFW's RF switches are bi-directional unless noted differently on the specification sheet.
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| 6) I need a custom RF switch designed. How much are your typical NREs (non-recurring engineering charge)? |
JFW does not charge NREs. Please send your custom requirement to sales@jfwindustries.com.
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7) Are your 18GHz Electro-mechanical Switches available with indicators or as latching?
Typical options: Latching, Self-terminating, Indicators, TTL, RoHS, non-RoHS
Typical DC supply options: +12, +15, or +28 Vdc |
