A 1–28 dB Attenuator Loaded 0.5-2.0 GHz Receiver Front-end Detecting IEMI Signals in 65 nm CMOS

We present a highly linear, 0.5-2 GHz receiver front-end for detecting high power intentional electromagnetic interference in TSMC 65 nm CMOS process. First, a single-ended 1–28 dB tunable attenuator matched to antenna 50 Ω impedance drives an active balun with minimal gain and phase mismatch across the wide bandwidth (BW). Second, the output of balun is filtered and downconverted separately in eight sub-bands with 200 MHz bandwidth. Harmonic mixing and crosstalk are minimized during the simultaneous processing of eight sub-bands. The fabricated prototype operates with 1.2 V supply voltage and consumes 264mW, demonstrating a 5.4dBm IP1 and a maximum BW-to-carrier frequency ratio of 1.2 in measurements. The attenuator has a return loss <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{S}_{11}\leq-10\text{dB}$</tex> across BW and different attenuator settings while consuming negligible power. Later, the downconverted sub-bands are digitized and processed off-chip to retrieve the IEMI signal accurately.