Flash memory and associated programming method

A flash memory, comprising:

• a program voltage generator for providing a constant program voltage during a detecting cycle and providing a dynamically-adjustable program voltage during a program cycle;
• a plurality of memory units for receiving the constant program voltage or the dynamically-adjustable program voltage, and outputting plural drain currents and plural data line voltages to plural data lines;
• a current limiter connected to the plural data lines for receiving a reference current and a reference voltage, thereby controlling the plural drain currents;
• and
• a multi-bit program control unit connected to the plural data lines, wherein 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, wherein during the program cycle, the specified data line voltage is used as a feedback voltage, and the dynamically-adjustable program voltage is generated by the program voltage generator according to the feedback voltage.