The Si4720/21 is the first single chip FM radio transceiver. The proven and patented digital architecture of the Si4720/ 21 combines the functionality of the Si470x FM radio receiver with the Si471x FM transmitter, offering full FM receive and transmit capabilities in a single, ultra-small 3x3x0.55 mm QFN package. The device leverages Silicon Lab's highly successful and proven FM technology, and offers unmatched integration and performance allowing FM receive and transmit to be added to any portable device by using a single chip. As with the Si470x and Si471x products, the Si4720/21 offers industry leading size, performance, low power consumption, and ease of use. The Si4720/21's digital integration reduces the required external components of traditional offerings, resulting in a solution requiring only an external inductor and bypass capacitor, and a PCB space of approximately 15 mm2. The Si4720/21 is layout compatible with Silicon Laboratories' Si470x FM radio receivers, Si473x AM/FM radio receivers, and the Si471x FM radio transmitter solutions, allowing a single PCB layout to accommodate a variety of music features. High yield manufacturability, unmatched performance,