一、产品特点及说明
The principle of the band-stop filter is that the input voltage is applied to the low-pass filter and high-pass filter at the same time, and then the output voltage of the two circuits is summed to obtain the band-stop filter. The function of the band-stop filter is to suppress the useless signal and noise in the band, so that the electromagnetic spectrum can be selected and allocated according to the application. The band-stop filter can limit the high-power transmitter to transmit signals in the specified frequency band and prevent the receiver from interference outside the operating frequency band. The principle of the ceramic band-stop filter is based on the characteristics of ceramic materials and resonance phenomenon, through the selection of appropriate ceramic materials and the design of reasonable resonator to achieve the filtering effect of specific signals.
Ceramic band-pass filter /Dielectric band-stop filter has a wide frequency range (300MHz-20GHz), input/output 50Ω (75Ω needs special description) impedance matching, input/output can be used interchangeably, easy to cascade use; Stable and reliable performance in the full temperature range, meeting the requirements of military working environment (-55℃ ~ +85℃); High near-end rejection, good phase consistency, small volume, high Q value, small standing wave, flat in-band amplitude-frequency characteristics, small insertion loss, high out-of-band rejection.
Dielectric band-stop filter
二、Model & Electrical characteristics
| Ceramic band-stop filter model and parameter table |
| Part No | Center frequency (MHz) | Band-stop Attenuation (dB) | Band-stop bandwidth (MHz) | Band resistance loss (dB) | Passband frequency (MHz) | Power (dBm) | Size(mm) |
| CMF33C1474F88A | 1474 | 21min | 1430~1518 | 1.0min | 600~1300 & 1670~3000 | 30 | 12*8.5*8.8 |
| QAF3R0363A | 1473.5 | 30min | 1468.5~1478.5 | 2.0min | 550~1429 & 1518~2750 | 3 | 12*12*3.9 |
| QAF3R0371A | 1795 | 20min | 1710~1880 | 3.0min | 3800~1582.5&2007.5~2500 | 3 | 12*12*3.9 |
| QAF3R0372A | 1542 | 20min | 1525~1559 | 3.5min | 380~1482.5 & 1601.5~2000 | 3 | 12*12*3.9 |
| Note: Due to many product models, only some representative models are listed in the table |
三、Application & attention
Dielectric band-stop filters are mainly used in aviation, aerospace, communications, electronic countermeasures, radar, radio and television and various electronic test equipment and high frequency systems. When using, it should be noted that the grounding end is well grounded, otherwise it will affect out-of-band suppression and flatness indicators. Do not use wave soldering during welding. If reflow welding is used, the recommended temperature is recommended. Do not soak when cleaning, it is recommended to wipe with alcohol. 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.
The ceramic band-stop filter design is flexible and can be customized according to customer requirements. The company has a variety of sizes of ceramic band-stop filter (dielectric band-stop filter) for users to choose. Because the indicators of microwave components are related to each other and sound to each other, the user needs to clearly state the indicator requirements before customization. This kind of product belongs to the relatively strong customization of the product, the product has been made, it cannot be changed. If there are indicators that exceed the physical limit of the material itself, the best indicators can be achieved through negotiation between the two parties.
