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APPLICATION NOTE
APN2014: 6 Bit 63 dB RF Digital Attenuator Solution 500–2000 MHz
High dynamic range systems often require an attenuator with a very wide attenuation range. It is possible to achieve 63 dB attenuation range by cascading two low cost digital attenuators, AA101-80 and AA104-73. It is effectively impossible to achieve such high attenuation range with a single package device.
AA101-80 is a 5-bit attenuator with a 1 dB least significant bit (LSB). Full-scale attenuation for this attenuator is 31 dB. AA104-73 is a 1-bit digital attenuator that produces 32 dB attenuation. When these two attenuators are cascaded on a standard FR4 printed circuit board, 63 dB total attenuation range with 1 dB step size is produced within the frequency range 500 MHz to 2 GHz.