Neurostimulation


Over the years, Microdul AG has gained experience in the field of medical applications, in particular neuromuscular stimulation. Two ASIC concepts for neurostimulation ASICs that can be implemented in different technologies are presented below.

The low voltage chip MS1031 is realized on Microdul's semicustom array MD500 and offers the possibility of monophasic and biphasic stimulation pulses in bipolar mode for voltages up to 8V. The amplitude of the pulses can be programmed up to 2.55mA with a resolution of 10µA. The programmable time sequences are realized with an internal or external oscillator of 100kHz.

The high voltage chip MS1032 can generate monophasic and biphasic stimulation pulses in monopolar mode for voltages up to 18V. Charge balancing can be realized with or without slow reversal (4:1). The amplitude of the pulses can be programmed up to 2.55mA with a resolution of 10uA. The programmable time sequences are realized with an internal or external oscillator of 100kHz. Overcurrent and undercurrent protection is part of the safety concept. The chip offers a switch matrix where the current sink/source channels and analog peripheral inputs can be flexibly assigned to the outputs of the switch matrix.

Feature Overview

Type MS1031 MS1032
Main feature 8-channel programmable current pulse generator 8-channel current sink/source for neuromuscular stimulation
Channel outputs 8 16
Pulse modes Monophasic
Biphasic
Monophasic
Biphasic
Biphasic with slow reversal (4:1)
Programable pulse parameters Timing Sequence Timing Sequence
Pulse polarity Anodic + Cathodic Anodic + Cathodic
Stimulation types Bipolar off / low / high
Max. stimulation current per channel
(* more channels can be connected in parallel for higher current output)
2.55mA 2.55mA
Programming resolution of the current 10uA 10uA
Current sink to source amplitude ratio 1:1 1:1
4:1
Output switch matrix no yes
Overcurrent and undercurrent protection no yes
Internal oscillator yes yes
External clock input yes yes
Voltage reference 1.25V 1.25V
Shutdown input (safety feature) yes yes
Cascading yes no
10 MHz SPI interface x yes
Operating voltage range 2.2V to 3.3V 1.8V to 4.5V
Operating temperature range +10°C to +50°C +10°C to +50°C
Packaging Various packaging options (die, flip-chip, packaged) Various packaging options (die, flip-chip, packaged)
Concept datasheet Link Link