Flash memory and associated programming method

The invention provides flash memory which includes a program voltage generator, plural memory units, a current limiter, and a multi-bit program control unit. The program voltage generator is used for providing a constant program voltage during a detecting cycle and providing a dynamically-adjustable program voltage during a program cycle. The plural memory units receives the program voltage and output plural drain currents and plural data line voltages to plural data lines. The current limiter is connected to the plural data lines and receives a reference current and a reference voltage, thereby controlling the plural drain currents. The multi-bit program control unit is connected to the plural data lines. During the detecting cycle, a specified data line voltage of the plural data line voltages with the minimum voltage level is detected by the multi-bit program control unit. During the program cycle, the specified data line voltage is used as a feedback voltage and transmitted to the program voltage generator to generate the dynamically-adjustable program voltage.