Integrated RF transmitter based on SAW oscillator

For the use in small, low power and low cost RF transmitters an oscillator ASIC in 1.2 my BICMOS technology operating at 433 MHz has been built. The ring oscillator topology with a phase shifter in the feedback loop provides as a novel feature also FM modulation. Integration of the osciallator ASIC together with the SAW resonator in a single package allows single device operation with very few external components.