======================BALUN_TRANSFORMERS======================================= Insertion_Loss_dB Loss from primary dot port to secondary dot port and secondary port. Most balun transformers are symmetrical through their central horizontal axis, therefore, an input can be applied at the primary dot port or the primary port with differential outputs at the secondary dot and secondary ports. Amplitude_Balance_dB Measure of the difference in amplitude between the two differential outputs. Phase_Balance_degrees Measure of difference phase between two differential outputs, i.e. measured from ±180¡. Return_Loss_dB Loss due to reflection at any port. ---------------------------------------------------------------------------- Flux Coupled Balun Transformers The flux coupled balun transformer can provide a wide range of impedance ratios; 1:1, 4:1, 9:1 and 16:1 are most common. DC isolation from primary coil to secondary coil is also a feature of this device. It has a low loss and good balance over a broad frequency bandwidth. The ETC4-1-2 has an insertion loss of approximately 2.5 dB at 800 MHz and is an example of one of our most popular flux coupled balun transformers. _ _ _ ___ / \/ \/ \ ___ | |___________| () () |________| | |___| | |___| | _ _ _ | / \/ \/ \ | ____| () () |____ | | | ___ | | |___| | | | _ _ _ | |___| | | / \/ \/ \ | |__/|\___| () () |____| | | _ _ _ ___ | / \/ \/ \ ___ | |_____|____| () () |_______| | |___| |___| _____________ | _______ | | | _ | | _______|___|___|_|_|_|_____ | | | | | | ___|___|___|_______ | ___ _____| |___| | | | | |______________________| | | ____| |_______| | | | | | |___| | | __| |___________| | |________________ BALANCED | | | | | | | | | ___ | | |___________ |_________________/|\______| | | | | | | | | | | |___| | |___________ | ________| |__/|\___|____ ___ | | | | | | _____| |___| _|_ |__| | |___________ | | | | __| |______ /// |___| | |_|_|_|_____|__|__|_| | | UNBALANCED | | | | | | ___ |_______________|__|__|_____| |_________| | | | |_____| | | |___| | |__________| | |_______________| ---------------------------------------------------------------------------- Transmission Line Balun Transformers The transmission line balun transformer comes in two impedance ratios as outlined above, i.e. 4:1 and 1:1. It operates at higher frequencies and over a greater bandwidth than the flux coupled balun transformer. It cannot provide DC isolation from primary side to secondary side. The ETC1.6-4-2-3 is an example of one of our most popular 4:1 transmission line balun transformers with an optimum performance of 1 dB insertion loss at 900 MHz. ___ ___ | |__ ____| | |___| \ / |___| _ | | _ / \/ \/ \ \_/\ /\_/ _ | | _ ___ / \/ \/ \_| | \_/\ /\_/ |___| _ | | _ / \/ \/ \ \_/\ /\_/ ___ | | ___ | |___/ \____| | |___| |___|