The present disclosure relates to a detection device. The detection device includes a power supply circuit, a convert circuit and a process circuit. The power supply circuit is configured to provide a first detection voltage and a second detection voltage, such that a specimen has current variation according to the first detection voltage and the second detection voltage. When the first detection voltage is switched to the second detection voltage, the convert circuit output a current variation signal according to the current variation of the specimen. The process circuit is coupled to the convert circuit and is configured to calculate a first correlation value of the specimen according to the current variation signal(e.g., HCT index).本揭示內容關於一種檢測裝置，包括一供電電路、一轉換電路及一處理電路，該供電電路用以提供連續之一第一檢測電壓及一第二檢測電壓，使得一檢體依據該第一檢測電壓及該第二檢測電壓具有電流變化；該轉換電路用以在該第一檢測電壓切換為該第二檢測電壓時，根據該檢體之電流變化輸出一電流變化訊號；該處理電路與該轉換電路電性連接，用以根據該電流變化訊號計算出該檢體之一第一相關數值（如：血球容積比指標）。
