A W-Band Low-Noise Amplifier With Resistor-Configured Temperature-Adaptive Biasing Achieving <1-dB Gain Fluctuation From −55 °C to 125 °C

This article presents a W-band low-noise amplifier (LNA) employing a resistor-configured temperature-adaptive biasing technique (RC-TABT), which ensures minimal gain fluctuation across a wide temperature range without requiring any external temperature sensing or digital calibration. An internal bias circuit, utilizing positive temperature-dependent transconductance (PTD-<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$g_{\text {m}}$</tex-math> </inline-formula>), is introduced to enhance the temperature stability of the LNA gain. By strategically combining resistors with different temperature coefficients (TCs), the circuit shapes the temperature response of the bias voltage, effectively mitigating temperature-induced gain variations. To evaluate the performance of the proposed method, a W-band LNA is fabricated using the IHP SG13G2 130-nm SiGe BiCMOS technology. Measurement results show that the LNA’s gain variation remains below 1 dB across the ultrawide temperature range of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$- 55~^{\circ }$</tex-math> </inline-formula>C to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$125~^{\circ }$</tex-math> </inline-formula>C, with a corresponding gain TC of 0.0056 dB/°C, significantly outperforming the 3-dB gain variation without the RC-TABT method. Under nominal operating conditions, the proposed LNA exhibits a peak gain of 12.46 dB, an average noise figure (NF) of 4.7 dB, and an output 1-dB compression point power (OP<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1dB</sub>) of 5.92 dBm. The LNA consumes 8.6 mW of power from a 3.3-V supply and occupies a compact core area of only 0.044 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>, with a RC-TABT unit occupying 0.0024 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>.