A Generic Test Board for the Electrical Characterization of ULP and ULV Fully-Differential Integrated Analog Circuits

Abstract

The characterization of ultra-low power (ULP) fully-differential/balanced amplifiers and active filters is challenging due to the incompatibility with the classical single-ended (SE) and 50 Ω 
impedance equipment. Interface circuits between the device under test (DUT) and the equipment are needed to perform the signal conversion and to work as voltage buffers. In this work, we propose a generic test circuits to be used in the characterization of ULP and ultra-low voltage (ULV) analog circuits. The test board includes balun transformers to the signal conversion, a high input impedance and low capacitance output driver and voltage regulators to provide the target DUT supply voltage. The characterization of the proposed PCB demonstrates a bandwidth of 30 MHz, output driver input impedance of 5 MΩ with 2.5 pF capacitance and low input-referred noise. The proposed circuit was applied to the electrical characterization of two fully-differential ULV and ULP analog integrated circuits.