Abstract: A charge pump for a flash memory. The charge pump includes: a current-guiding circuit having a first, a second, and a third output; and a first, a second, and a third charge unit. The current-guiding circuit has two diode-connected transistors respectively connected between the first and the second outputs, and the second and the third outputs. Each of the charge units, for storing charge, has two ends. The first, the second, and the third charge units respectively have one end connected to the first, the second, and the third outputs, and the other end of the third charge unit is connected to the first output.