Sense-amplifier circuit of memory and calibrating method thereof

A calibrating method for a sense-amplifier circuit, comprising steps of:

• providing the sense-amplifier circuit, comprising:
• a sense-amplifier unit constituted by a plurality of transistor switches and having a first connection terminal, a second connection terminal, a third connection terminal and a fourth connection terminal;
• a first switch unit configured to be parallel coupled between the first and second connection terminals of the sense-amplifier unit;
• a second switch unit configured to be parallel coupled between the third and fourth connection terminals of the sense-amplifier unit;
• and
• a control unit configured to electrically couple to the first and third connection terminals of the sense-amplifier unit thereby forming a first feedback path and a second feedback path, respectively, the control unit having a plurality of output terminals configured to electrically couple to the parallel-coupled transistor switches gate terminals of which in the first and second switch units with one to one correspondence;
• simultaneously supplying a same voltage signal to the first and third connection terminals of the sense-amplifier unit;
• detecting a voltage level at each of the first and third connection terminals of the sense-amplifier unit in a next clock sequence and determining whether or not the first and third connection terminals have a same voltage level;
• and
• outputting at least a control signal to the parallel-coupled transistor switches gate terminals of which from the control unit if the first connection terminal has a different voltage level from the third connection terminal, wherein the control signal selectively turns on at least a parallel-coupled transistor switch in the first or second switch units so as to calibrate a sensing range of the sense-amplifier unit.