Ultra-low power wakeup circuit device

An ultra-low power wakeup circuit device, comprising:

• a keyboard with N scan lines, having a key installed in between every two scan lines, where N is an integer greater than one;
• a key scan circuit connected to the N scan lines for sequentially outputting scanning signals from first scan line to N-th scan line in a predetermined time, thereby acquiring N key scan data of the N scan lines when a specific key is pressed and two scan lines corresponding to the specific key are short-circuited, the key scan circuit processing the N key scan data to generate a current key scan data;
• a storage unit connected to the key scan circuit for temporarily storing the current key scan data as a previous key scan data;
• and
• a comparator unit connected to the key scan circuit and the storage unit for comparing the current key scan data with the previous key scan data and generating a wakeup signal when the current key scan data is different from the previous key scan data.