一、Characteristics
The main function of Barron filter is to do the conversion of balance and non-balance, and can suppress stray signals, improve the anti-interference ability of the system, filter out the play signal, and make the useful signal pass with low loss. Barron filter as a three-port device (one unbalanced input port, two balanced output ports), Barron filter can be unbalanced input port signal output from two balanced output ports, while the two output port signal amplitude is the same, phase difference of 180°, Barron filter can also be used as a balanced unbalanced converter.
Barron filter has the advantages of low differential loss, multiple impedance conversion, high out-of-band rejection, wide band and so on. In the production process, the LTCC wiring process is used to reduce the volume of Barron filter, and at the same time, the dielectric material with low dielectric constant (9.8) is used, whose size can be 1.6*0.8*0.6mm, and the insertion loss is less than 1.5dB in the frequency range of 1.85GHz~2.695GHz. The phase unbalance degree is less than ±10°, which can fully meet the needs of miniaturization of modern communication equipment, and is also an indispensable microwave component connecting the transmitter and receiver.
Barron filter
二、Electrical Characteristics
| LTCC Barron filter (low temperature co-fired ceramic Barron filter) model and parameter table |
| Part No | Frequency(MHz) | Insertion loss(dB) | Phase difference | Unbalanced impedance | Impedance(Ω) | Size(mm) | SPEC |
| LBF18M2450H1512-M32 | 2400 - 2500 | ≤ 2.1 | 180±5 deg
| 50Ω | Complex conjugate to nRF51822 & nRF51422 | 1.6*0.8*0.6 |  |
| LBF21M2450H127-M37 | 2400 - 2500 | ≤ 1.5 | 180±10 deg | / | Complex conjugate to AT86RF230/231 and ATmega 128RFA1 | 2.0*1.25*0.95 | |
LBF22M2595H132-M36
| 2500 - 2690 | ≤ 3.0 | 180±10 deg | 50Ω(25Ω+25Ω) | 50：50 | 2.5*2.0*1.2 | |
| Note: Due to many product models, only some representative models are listed in the table |
三、Application & attention
Barron filters can be widely used in antenna modules, mixers, phase shifters, Bluetooth, WiFi, wireless LAN and connecting RF front-end transmitters and receivers. In use, but pay attention to the grounding end is well grounded, otherwise it will affect the out-of-band suppression and flatness indicators, welding temperature should not be too high, the time should not be too long, recommended temperature. Do not use wave soldering. Products should be stored in the ambient temperature of -10℃~40℃, relative humidity is not more than 80%, the surrounding environment is not acidic, alkaline and other harmful gases in the warehouse. It is recommended to wipe with alcohol when cleaning.
The company can customize LTCC Barron filter, this kind of product is a strong customization of the product, once the product is made, it cannot be changed. Before ordering, the parameter requirements of the device should be clearly stated. For the parameter requirements beyond the physical limit of the material, the best indicators can be achieved through negotiation.
