On-Chip Temperature Compensation for Small-Signal Gain Variation Reduction.

Area of Science:

• Electrical Engineering
• Semiconductor Device Physics
• Microwave Engineering

Background:

• Power amplifier (PA) performance, specifically small-signal gain (S21), is highly sensitive to temperature variations.
• Increasing temperatures typically lead to a decrease in PA's S21, degrading overall performance.
• Existing methods for temperature compensation may be complex or inefficient for high-frequency applications.

Purpose of the Study:

• To design and implement an effective on-chip temperature compensation circuit for power amplifiers.
• To mitigate the degradation of small-signal gain (S21) caused by temperature fluctuations.
• To validate the compensation circuit's performance in a differential stacked millimeter-wave wideband PA.

Main Methods:

• A novel compensation circuit comprising two diodes and four resistors was designed.
• This compensation circuit was integrated into a differential stacked millimeter-wave wideband power amplifier.
• The PA was designed and simulated using a 55 nm CMOS process.

Main Results:

• Post-layout simulations demonstrated a significant reduction in S21 fluctuation from 2.4 dB to 0.1 dB.
• This improvement was observed over an extensive temperature range of -40 °C to 125 °C.
• The compensation circuit maintained performance across the 25-40 GHz frequency band.

Conclusions:

• The proposed on-chip temperature compensation circuit effectively stabilizes PA small-signal gain over wide temperature variations.
• The circuit is suitable for high-frequency applications, including millimeter-wave and microwave power amplifiers.
• The compensation technique is applicable to multi-stage cascaded PA designs, offering broad utility.