Calculator

The invention discloses a calculator which comprises a power supply, a display screen connected with the power supply and an operation circuit, and is characterized by further comprising a backlight control circuit which is connected with a touch panel electrically and used for controlling the backlight brightness of the display screen according to a touch signal; a charging circuit which comprises a charging control circuit and a peripheral auxiliary circuit and also comprises an anti-reverse charging circuit, an undervoltage lockout circuit, a thermal feedback circuit and a soft start circuit. The peripheral auxiliary circuit further comprises a safety circuit, a thermal regulation circuit, a charging mode detection circuit and a reverse polarity protection circuit. Compared with the prior art, the calculator has the beneficial effects that the backlight brightness of the display screen can be adjusted, power can be supplied to other electric appliances or from charging, in order toensure the stability of t