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This paper presents an improved interface for eddy current displacement sensor for accurate displacement measurement of thin targets in harsh environment. Two recently proposed state-of-the-art interfaces are analyzed and experimentally verified. The experimental results confirm high level of performance: displacement measurement of a 100 um thin target; displacement range ±1.5 mm; 15 bits dynamic range; 1 kHz signal bandwidth; 18-mW power consumption. The most important application constraints of the two interfaces are discussed, which facilitates a correct choice when targeting a specific set of application requirements. A new interface, which demonstrates the above mentioned performance, and at the same time allows continuous time displacement measurement useful in control loops and servo systems, is presented and evaluated.