A 0.5-V, 440-µW frequency synthesizer for implantable medical devices

Abstract

This paper presents an ultra-low-power, low-voltage frequency synthesizer designed for medical implantable devices. Several design techniques are adopted to address the issues in ultra-low voltage design. The charge pump (CP) in the synthesizer utilizes dynamic threshold-voltage and switch-coupled techniques to provide a high driving current while maintaining a low standby current. The synthesizer adopts a ring-based voltagecontrolled oscillator (VCO) that utilizes a dual resistor-varactor tuning technique for compensating process-voltage-temperature (PVT) variations and the exponential voltage-to-current curve. Implemented in a 130-nm CMOS technology, the 0.5-V medicalband frequency synthesizer consumes 440 µW with a phase noise of -91.5 dBc/Hz at 1-MHz frequency offset.

A 0.5-V, 440-µW Frequency Synthesizer for Implantable Medical Devices

“…In this paper, we expand on the 0.5-V 440-W PLL design presented in [15]. An implantable device for radiation cancer therapy application utilized the proposed PLL, as discribed in [16].…”