A V-Band Power Amplifier With 1-dB Step Saturated Power Control for Multimode Radar Applications

This letter presents a V-band high-efficiency power amplifier (PA) with 1-dB step saturated output power (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${P} _{\mathbf {sat}}$ </tex-math></inline-formula>) control resolution to support different radar applications. The power control is accomplished by digitally programming the transistor width of the 6-bit power-stage <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${g} _{\mathbf {m}}$ </tex-math></inline-formula> arrays. The two-way current-combining technique improves the output power and efficiency with a compact area. The PA is fabricated in 65-nm CMOS and occupies a compact core area of 0.079 mm<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{\mathbf {2}}$ </tex-math></inline-formula>. It achieves a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${P} _{\mathbf {sat}}$ </tex-math></inline-formula> of 13.6 dBm with a 28.5% peak power-added efficiency (PAE) at 60.5 GHz. The measured <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${P} _{\mathbf {sat}}$ </tex-math></inline-formula> is >11.6 dBm at 55–67 GHz and has a 7-dB tuning range with a 1-dB step. The measured <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${P} _{\mathbf {sat}}$ </tex-math></inline-formula> control error is <0.21 dB with calibration.