Analog Devices has developed the ADRF5476, a silicon-based, 2-bit digital step attenuator that operates over a frequency range from 1 to 72 GHz frequency. This attenuator has a 12 dB attenuation range with a 4 dB step size and bidirectional operation, allowing either RF port to be configured as the input or output. The attenuator is specified with insertion loss below 3.0 dB across the full frequency range, with typical values of 0.9 dB up to 18 GHz, 1.3 dB up to 40 GHz, 2.1 dB up to 67 GHz, and 3.0 dB at 72 GHz. The RF ports are designed to match a 50 Ω characteristic impedance. This 50 Ω matched attenuator has a step accuracy specified at ±0.50 dB up to 55 GHz and ±0.75 dB up to 72 GHz.
The ADRF5476 has an input P0.1 dB compression point greater than 24 dBm and a third-order intercept point (IP3) greater than 45 dBm. The RF ports support 24 dBm steady-state and 24 dBm hot-switching power handling across all attenuation states. This attenuator is specified with no low-frequency spurious signals, which is relevant for wideband and high-frequency RF systems.
It has a control that is provided through a parallel digital interface compatible with CMOS and LVTTL logic levels. This RF digital attenuator has an RF amplitude settling time of 55 ns, measured from a 50% control signal transition to within 0.1 dB of the final output level. It supports parallel-mode digital control for attenuation state selection.
The ADRF5476 operates from ±3.3 V supply rails, drawing approximately +124 µA from the positive supply and −528 µA from the negative supply, as specified in the electrical characteristics. This device is supplied as a 14-ball flip-chip bare die, measuring 1.940 mm × 1.160 mm, and is specified for operation over a −40 °C to +105 °C temperature range. Applications include test and measurement equipment, 5G mmWave infrastructure, microwave radios, VSAT systems, and military and aerospace platforms such as radar and electronic countermeasure systems.