title: A generic miniature multi-feature programmable wireless powering headstage ASIC for implantable biomedical systems.
abstract: Wireless powering holds immense promise to enable a variety of implantable biomedical measurement systems with different power supply and current budget requirements. Effective power management demands more functionality in the headstage design like power level detection for range estimation and power save modes for sleep-wake operation. This paper proposes a single chip ASIC solution that addresses these problems by incorporating digitally programmable features and thus has the potential to enable wireless powering for many implantable systems. The ASIC includes an RF rectifier which has a peak efficiency of 17.9% at 900 MHz and 11.0% at 2.4 GHz, a robust 1 V bandgap reference and LDO voltage regulator whose output can be programmed in the range of 1 V-1.5 V, and can drive upto 4 mA of load current. The input RF power level detector has a threshold of 1.6 V and the power management block can be programmed to give a 6%, 12.5% or 25% duty cycle power line to the transmitter resulting in upto 60% reduction in average power. The ASIC was fabricated using the TSMC 65 nm process, occupies 1mm(2) die area and the headstage consumes ~300 μA at 1.2V regulated supply.
authors.affiliation: Center for Implantable Devices, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47906-2032, USA. rchinnak@purdue.edu
authors.forename: Rajkumar
authors.initials: R
authors.lastname: Kubendran
authors.forename: Harish
authors.initials: H
authors.lastname: Krishnan
authors.forename: Bhupendra
authors.initials: B
authors.lastname: Manola
authors.forename: Simon W M
authors.initials: SW
authors.lastname: John
authors.forename: William J
authors.initials: WJ
authors.lastname: Chappell
authors.forename: Pedro P
authors.initials: PP
authors.lastname: Irazoqui
mesh_terms: D011211:Electric Power Supplies; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008904:Miniaturization; D019736:Prostheses and Implants; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D013686:Telemetry / Q000295:instrumentation*