Balun-Filter Combinations

What is an RF balun-filter combination?

An RF balun-filter combination is an integrated passive component that combines balanced-to-unbalanced signal conversion with RF filtering. Johanson Technology’s balun-filter combinations are designed to simplify wireless front-end integration by performing both functions within one compact surface-mount component

What is the difference between a balun and a balun-filter combination?

A balun converts between balanced and unbalanced RF signals and may also provide impedance transformation. A balun-filter combination adds RF filtering to the balun function, helping attenuate unwanted out-of-band signals or harmonics. The integrated approach can replace several discrete components when its frequency, impedance, insertion-loss, and rejection characteristics meet the system requirements

What does harmonic filtering do in an RF front end?

Harmonic filtering attenuates unwanted frequency components outside the intended operating band. In an integrated balun-filter, this filtering is combined with balanced-to-unbalanced conversion to support a cleaner RF signal path and reduce the number of separate filtering components required in the front end

What wireless applications use balun-filter combinations?

Johanson Technology identifies Bluetooth, Zigbee, Wi-Fi, IoT, embedded wireless systems, smart-home products, wearable devices, and industrial wireless equipment as typical applications. Available components cover multiple operating bands and impedance configurations

What is a chipset-matched balun-filter?

A chipset-matched balun-filter is designed around the RF interface requirements of a specified wireless chipset or chipset family. Johanson’s current product table includes options identified for selected Texas Instruments devices, including CC1352P, CC1352P7, CC1354P10, CC1311P3, and CC1312P. Compatibility should be confirmed against the full part-number datasheet and the chipset manufacturer’s current design guidance

Why is insertion loss important when selecting a balun-filter?

Insertion loss represents the signal loss through the component within its operating band. Lower insertion loss generally preserves more of the available RF signal, but it must be evaluated together with impedance matching, phase balance, filtering, rejection, bandwidth, and other system requirements. Johanson lists insertion-loss values for individual balun-filter part numbers.

What does out-of-band rejection mean for a balun-filter?

Out-of-band rejection describes how effectively the filter attenuates signals outside its intended passband. The required rejection depends on the wireless standard, transmitter output, harmonic frequencies, receiver environment, antenna path, and applicable system requirements. Engineers should review the frequency-response data for the selected Johanson part rather than relying only on the nominal operating-frequency range.