PROBLEM TO BE SOLVED: To reduce the development man-hours of an electrocardiograph capable of measuring a plurality of leads and to develop and manufacture at low cost. SOLUTION: By using three or more electrodes, two or more 1-lead electrocardiographic measurement chips 110, and one power supply or battery 104, the 1-lead electrocardiographic measurement chips 110 respectively have a positive electrode 101 and a negative electrode 102 by electrodes. A biosignal can be input from the GND electrode 103, and an electrocardiographic signal can be output depending on the combination of the biosignals of the positive electrode 101, the negative electrode 102, and the GND electrode 103 that have been input. [Selection diagram] Fig. 1【課題】複数の誘導を測定できる心電計の開発工数を減らし、安価に開発・製造させる。【解決手段】３以上の電極と、２以上の１誘導心電測定チップ１１０と、１つの電源またはバッテリー１０４により、１誘導心電測定チップ１１０はそれぞれ、電極により正電極１０１と負電極１０２とＧＮＤ電極１０３とから生体信号を入力され、入力された正電極１０１と負電極１０２とＧＮＤ電極１０３の生体信号の組み合わせに応じて、それぞれ心電信号を出力することができる。【選択図】図１
