Comparative analysis of CML and MOS differential Automatic Amplitude Level control regulators for built-in-self-test applications

This paper presents Automatic Amplitude Level Regulators (AALR) as a practical Built-In-Test (BIST) and demonstrates its application for on-chip testing and local Calibration of integrated RF blocks. The proposed circuit performs full-wave rectification and generates a dc voltage proportional to the amplitude of an RF signal over a wide frequency range. Both CML and MOS RF AALR are designed and fabricated using NXP-Semiconductors advanced BiCMOS technology process. Very low area occupation with low power consumption are demonstrated for a wide-range of RF input signal power. Digitally controlled bits are introduced for scalable amplitude-level adjustment and control. Measurements show that fabricated RF test devices demonstrate detection dynamic range of 21 dB from 25 MHz to 5 GHz. Advantages and limitations of designed CML and MOS RF regulators are drawn based on careful correlation analysis between simulations and measurement results.