Implantable neuro-monito-stimulation system dedicated to enhance the bladder functions

Abstract

This paper concerns the design and implementation of a new implantable Neuro-Monito-Stimulation System (NMSS) for the urinary tract rehabilitation in paraplegics. In addition to selective stimulation for voluntary micturition and permanent stimulation for reduction of the detrusor overactivity, the NMSS includes telemetry capabilities of electrodes-tissues contact. Resistance up to 10kΩ could be measured with good linearity and sent wirelessly to an external controller at 1 kbps data transmission rate. With an embedded rechargeable battery, the implant lifetime is significantly extended up to 1000 cycles of 250 hours with nominal operating conditions. The NMSS design is described with the main system solutions and the preliminary experimental results.

Miniaturized SiP supply board based on TPVD charge pump ICs for high-voltage biomedical applications

“…Note that, given a concrete I L value, it is not possible to obtain regulated output voltage values (V out [1]REG, V out [2]REG ) greater than the values that would be obtained in an unregulated scenario (V out [1], V out [2] ). Hence, both unregulated V out[n] curves (Fig.…”

“…Thus, it can be stated that, ideally, the cascade connection of n ideal TPVD circuits with Vin[n] = Vout[n- 1] leads to a situation where Vout[n] = 2nVin [1]. Hence, theoretically, a 2-stage (n = 2) cascade connection of TPVD circuits using a 3.3 V battery as input voltage Vin [1] would provide an output voltage Vout [2] = 13.2 V. Actually, the real output voltage V out that can be obtained through the single-stage TPVD architecture depends on many design/application parameters and usually is lower than the result given by the ideal analysis. The size (W k /L k ) of the S k transistors, which is directly related to their on-resistance R dsk values and their parasitic capacitances, the values of C f and C L capacitors, the switching frequency f s = 1/T of CLK k clock signals, the input voltage V in , and the value of the active load R L (which sets the load current I L ) are parameters that have a direct influence in the unregulated steady-state V out value that is really obtained.…”

“…Figs. 2 and 3 shows a comparison between the results provided by the simulation of the model given by (1) with the ones obtained through SPICE-based simulations of a 2-stage unregulated TPVD circuit (Vin [2] = Vout [1], Vin[1] = 3.3 V) using two HV integration technologies, I 2 T100 BCD 0.7 ȝm from ON semiconductor and 0.8 ȝm 5/20V CMOS-DMOS from DALSA semiconductor, with the following design/aplication parameters: V in = 3.3 V, C f = C L = 1 ȝF, R L = variable, S k width W Sk = 10000 ȝm for PMOS type, S k width W Sk = 5000 ȝm for NMOS type, lenght L Sk(I2T100)min = 3.4 ȝm for PMOS and NMOS type, lenght L Sk (DALSA)min = 6 ȝm for PMOS and NMOS type, CLK switching frequency f s = 100 kHz. Vout [1] vs IL results (SPICE-based --♦--and model --Ɣ--data) showing the relative error of the between simulated and model data for 0.7μm I 2 T100 BCD technology from ON semiconductor.…”

“…Thus, for a 2-stage cascade configuration Vout [2]REG is given by (3) where Į [n] [n=1..2] is fixed by choosing R 1 , R 2 , R 3 , and R 4 values in the corresponding PSFR circuit. Note that, given a concrete I L value, it is not possible to obtain regulated output voltage values (V out [1]REG, V out [2]REG ) greater than the values that would be obtained in an unregulated scenario (V out [1], V out [2] ).…”

“…Biomedical devices are one of the hardware applications where HV I/Os driving capability is required. Pacemakers [1], implantable functional electric stimulators (FES) for bladder control [2], paralyzed muscle recovery systems [3], or intracortical nerve microstimulators [4], are examples of such devices where voltages between 9 and 13 V are required. All these HV systems are usually battery-powered devices which have small size and are implanted inside the human body.…”