| 摘要 |
<p>The present invention detects the current cumulative value with extremely high accuracy while using an inexpensive AD converter having low resolution. A current detection circuit (1) is provided with: a current sensor (8) for detecting the current of a battery (3); an AD converter (9) for converting an analog signal detected by means of the current sensor (8) into a digital signal; a current counting circuit (11) for adding the current values converted into digital signals by means of the AD converter (9) and for computing the current cumulative value; and a noise generation circuit (10) for inputting a noise signal, which does not contain a signal of the integral multiple of a sampling frequency of the AD converter (9), to the input side of the AD converter (9). The voltage inputted into the AD converter (9) from the current sensor (8) by means of the noise generation circuit (10) functions as a current signal to which the noise signal was supplied. Said current signal is converted into a digital signal by means of the AD converter (9) and the digital signals outputted from the AD converter (9) are added by means of the current counting circuit (11), thereby detecting the cumulative value of the current circulating the battery (3).</p> |
