近幾年來，人們致力於發展植入式腦機介面微系統，希望能結合記錄單元與刺激單元，藉由記錄單元偵測腦中異常訊號，透過類比數位轉換器(ADC)轉成數位訊號，經由數位訊號處理(DSP)後，來進行病情診斷，並利用刺激器提供相對應的電刺激訊號來進行神經訊號調整，以抑制腦部不正常放電。
對於植入型神經電刺激器，功率消耗(power consumption)是決定電池大小的關鍵因素，提升能量轉換效率能夠縮小電池的尺寸以及增加電池壽命，當裝置的尺寸變小以及使用時間變長時，對病患的安全跟舒適度都能大大提升，因此提升電刺激器的能量轉換效率是首要目標。
本論文在低電壓系統1.8V/3.5V中設計一個能應用於腦機介面，可提供深層腦部電刺激治療的電流可調式神經刺激器，能提供70uA到4mA(6 bit)的電流刺激，並能透過外接的電阻校正刺激電流，且利用動態調整供應電壓技術追蹤電極電壓，提升刺激效率。而升壓電路選擇效率較高的CCTS電荷幫浦，它能產生最高12V的電壓供刺激使用。為了提高刺激效率，此供應電壓能偵測電極上的電壓，並藉由回授系統調整輸出電壓，使用一個四位元的電壓數位類比轉換器改變刺激電壓，變動範圍從3.5V到12V。電荷幫浦本身使用級數控制電路技術，在較低輸出電壓時，能自動改變電荷幫浦級數，提高能量轉換效率。
本晶片透過台積電T18HVG2製程完成下線，而電荷幫浦有完成量測，並驗證晶片功能。

In recent years, people have devoted themselves to the development of implantable brain-computer interface microsystems, hoping to combine the recording the unit and the stimulation unit. They use the recording unit to detect abnormal signals in the brain, and convert them into digital signals through an analog-to-digital converter(ADC). And digital signals after being processed by the signal processing converter(DSP), the condition is diagnosed, and the stimulator is used to provide the corresponding electrical stimulation signal to perform DBS, so as to inhibit the abnormal discharge of the brain.
For implantable electrical neural stimulators, power consumption is a key factor in determining the size of the battery. Improving energy conversion efficiency can reduce the size of the battery and increase battery life. When the size of the device becomes smaller and the using time becomes longer, the safety and comfort of patients can be greatly improved, so improving the energy conversion efficiency of the electrical stimulator is the primary goal
This paper designs a current-tunable neural stimulator that can be applied to the brain-computer interface and provide deep brain electrical stimulation therapy in the low-voltage system 1.8V/3.5V. It can provide stimulation current from 70uA to 4mA (6 bit), this current can be calibrated through an external resistor. It also uses dynamic power supply technology to trace electrode voltage, improving stimulation efficiency. And the boosted circuit we select a CCTS charge pump, which can generate a maximum voltage of 12V for stimulation. For improving the efficiency of stimulation, the supply voltage can be detected from the electrode, and adjust the output voltage through the feedback system by a four-bit voltage digital-to-analog converter which is used to change the stimulation voltage (3.5V to 12V). The charge pump also uses the stage select circuit technology to improve the energy conversion efficiency, which can automatically change the charge pump stage when the output voltage is low.
This chip is taped-out in the TSMC T18HVG2 process. The charge pump has completed the measurement, and verified the function of the chip.

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