A mixed-signal ASIC for triple-chamber cardiac pacemakers with heart resistance measurement

This paper presents a mixed-signal ASIC for triple-chamber pacemakers. The ASIC performs four major functionalities: 1) sensing of heartbeat signals; 2) measuring the heart resistance of three chambers independently to diagnose the attachment status of the electrodes and provide additional information about the pathological status of the patient's heart; 3) generating stimulus pulses with programmable magnitude and pulse width; 4) receiving commands and configuration data from MCU, and transferring register data to MCU through the SPI interface. The ASIC is fabricated in a 0.35-μm BCD technology with a chip area of 3.8×3.8 mm2. Measurement results show that the magnitude of the stimulus pulses can be programmed from 0. 1 to 7.4 V with 0.1-V step. Almost linear heart resistance measuring is achieved in the resistance range of 250 to 4000 Q. Average current consumption is 4 μA from a 2.8-V supply.

[1]  Refet Firat Yazicioglu,et al.  A 13 $\mu {\rm A}$ Analog Signal Processing IC for Accurate Recognition of Multiple Intra-Cardiac Signals , 2013, IEEE Transactions on Biomedical Circuits and Systems.

[2]  Wojciech Zareba,et al.  Cardiac-resynchronization therapy for the prevention of heart-failure events. , 2009, The New England journal of medicine.

[3]  Refet Firat Yazicioglu,et al.  A 680 nA ECG Acquisition IC for Leadless Pacemaker Applications , 2014, IEEE Transactions on Biomedical Circuits and Systems.

[4]  You-Yin Chen,et al.  A Programmable Implantable Microstimulator SoC With Wireless Telemetry: Application in Closed-Loop Endocardial Stimulation for Cardiac Pacemaker , 2011, IEEE Transactions on Biomedical Circuits and Systems.

[5]  L. Wong,et al.  A very low power CMOS mixed-signal IC for implantable pacemaker applications , 2004, 2004 IEEE International Solid-State Circuits Conference (IEEE Cat. No.04CH37519).

[6]  Howard Tang,et al.  A 5.8 nW 9.1-ENOB 1-kS/s Local Asynchronous Successive Approximation Register ADC for Implantable Medical Device , 2014, IEEE Transactions on Very Large Scale Integration (VLSI) Systems.