Switches

An RF switch is a digitally-controlled component that connects one input port to one of several output ports (or vice versa). The single-pole-double-throw (SPDT) configuration is the workhorse: one common port plus two switched ports, controlled by a single digital line. Switches let a system reuse the same physical signal path for multiple purposes — transmit and receive on a TDD radio, two antennas on a diversity receiver, an amplification path versus a bypass path on an LNA-with-bypass, or different filter paths in a multi-band radio.

Selection comes down to four numbers: frequency range, insertion loss (the dB the through-path adds — lower is better), isolation (the dB of attenuation between an inactive port and the common port — higher is better, drives transmit-receive isolation in TDD systems), and switching speed (how fast the switch transitions, often sub-microsecond for TDD). Power handling and IIP3 also matter when the switch sees the transmit signal directly.

Typical applications include TDD cellular and DAS radios (transmit/receive switching), antenna diversity in MIMO receivers, band-select switching in multi-mode radios, signal routing inside calibration loops, and bypass-path routing inside complex amplifier modules.

The table below lists the active SPDT switch portfolio sorted by SKU, with frequency range, insertion loss, isolation, IIP3, supply, and package. Click any SKU for the full data sheet, S-parameters, and reference designs.