Floating-G_m-based current sensors are effective in rejecting PWM common-mode voltage. But their linearity drops at high voltages due to substrate-current-induced body effect in LDMOS devices. To address this issue, this work introduces a DLL-assisted dynamic body biasing sensor in 0.18μm BCD, improving HD2 by 31dB and THD+N by 14dB. And a peak THD+N of -82.3dB is achieved in the meanwhile. It supports 60V common-mode, rejects PWM up to 2MHz, and enables high-linearity sensing for high power audio and motor-driver systems.

This paper presents a test structure for a 27 mΩ diffusion current sensing resistor, designed to analyze distortion caused by self-heating in audio power amplifiers. A parallel Kelvin connection minimizes parasitic effects, reducing resistance error to 0.4% and temperature coefficient error to 0.7%. A diode-based temperature sensor array enables accurate measurement of temperature variations, allowing the characterization of HD3 with an inaccuracy of