SF2098H

Surface acoustic wave (SAW) filters are important components for RF (radio frequency) signal processing in communication systems. The SF2098H is a very popular SAW device whose application field and working principle are widely discussed in this paper.

SAW filters are employed in various application fields, ranging from mobile communication systems, satellite-based navigation systems, radar systems, as well as television broadcast industries. By allowing a signal to pass through its passband while blocking any frequency outside the passband, SAW filters are able to provide high-frequency selectivity and performance.

The SF2098H has an overall size of 2.5 x 1.6 millimeters and an insertion loss of 0.37 dB, resulting in excellent suppression of unwanted signals outside its operating frequency. The low profile of the device makes it highly suitable for use in space-limited applications such as on-chip and on-board integration.

The working principles of the SF2098H are based on the resonant vibrational characteristics of an acoustic waveguide, which is formed by a piezoelectric substrate and two close interdigital transducers (IDTs). The IDTs are engineered to behave as series of high-frequency and low-loss resonators, which perform frequency selection and filtering. When an input signal is applied to the IDT that has its lower electrode connected to a grounded path, a continuous wave of longitudinal acoustic energy travels through the piezoelectric substrate. This traveling acoustic wave reaches the second IDT at a certain frequency, which is then associated with the resonance frequency of a particular path due to its length. Hence, the SF2098H is able to suppress frequencies outside and provide high-frequency selectivity within its passband.

In conclusion, the SF2098H can is a popular SAW device, designed for use in space-limited applications. Its small size and high-frequency selectivity make it ideal for filtering various RF signals in communication systems, radar systems, navigation systems, and television broadcasts.