Thin-Film 3-dB Couplers Uncomplicate RF Design

Wireless applications that need quicker design options may benefit from a new group of thin-film 3-dB hybrid couplers. The miniature surface-mount components from AVX Corp. come in a wide range of frequencies, including 800 ± 30 MHz and 2325 ± 50 MHz and above (see the figure) .

The four-port coupler splits the input signal into two equal amplitude outputs with phases shifted by 90°. Insertion loss is in the 0.25- to 0.35-dB range. Typical return loss is 20 dB. The devices can operate at power levels up to 10 W continuous with a maximum phase balance of 3°.

These hybrid couplers, designated DB0805, suit virtually all mobile communications applications, including GSM, PCS, and WCDMA. Other uses include RF balanced amplifiers and signal distribution in basestations. Samples are available now. Lead time for volume orders is seven weeks. Typical prices are in the $0.75 range for 1000-unit quantities.