Rssi or received signal strength indication is a very popular circuit used in many radios to indicate the level of the received signal under various conditions. It typically consists of a series of limiting amplifiers followed by rectifiers and voltage to current converters that generate the rssi output signal. Recently Signal Processing Group Inc., released a rssi indicator IC that can work up to 450 Mhz.Its typical operation was tested at 70 Mhz and 300 Mhz and its rssi characteristic was published. This characteristic is reproduced below. Interested parties may contact us through our website for actual packaged silicon for purchase, design notes, application notes, IP etc.Modifications to the rssi design can be done as requested by interested customers and re-fabricated. The chip is designed in a 0.6 um BiCMOS process available from a popular foundry service.