
Mini-Circuits’ BBFCG-family of LTCC products that integrate a balun transformer and bandpass filter together in a single device has proven valuable in saving space and simplifying board layouts in a variety of applications, and they continue to gain popularity in customer designs.
Model BBFCG2-362+ was recently selected by a leading telecom customer for use in their 5G massive MIMO base station designs. Minimizing size is an essential requirement for 5G m-MIMO systems using 64/32 transmitter and 64/32 receiver channels in a compact antenna array. This product integrates two discrete components on the customer’s board into one and measures just 0.079″ x 0.049″ x 0.037” (2.01 x 1.24 x 0.94 mm), providing advantages of smaller size, lower cost and higher reliability.
The latest 5G system-on-chip devices have integrated high-speed A/D converters (ADCs) using differential input signals, which require a balun to convert the single-ended signals typically used in transmitter power amplifiers, receiver low noise amplifiers, and digital pre-distortion (DPD) feedback signals. They also require an anti-aliasing filter to eliminate noise and wideband spurs in the Nyquist zone of the ADC. BBFCG2-362+ has a passband from 3250 to 3950 MHz, ideal for 5G systems operating in the n48 (CBRS) and n78 frequency bands while combining the filtering and balun elements of the circuit into a tiny ceramic monolith. A simplified block diagram of the balun-filter in this architecture is shown below for reference.

The benefits of these products are far from exclusive to this use case. Additional models currently in stock span passbands from 960 to 5875 MHz, offering a range of options for designers developing telecom equipment for 5G and 4G/LTE network infrastructure interested in replacing discrete baluns and filters in their current designs. We’re developing new designs for all the primary 5G bands, and we can also develop customized models, so please reach out to apps@minicircuits.com if you’re looking for different passband frequencies.
You must be logged in to post a comment.