Data slicer capable of automatically removing current mismatch between current pumps incorporated therein and its operating method

A data slicer comprising:

• a comparator for comparing an analog signal with a slice reference level to convert the analog signal into a digital signal;
• a counter electrically connected to the comparator for calculating a digital sum value during a predetermined period according to logic values carried by the digital signal;
• and
• a voltage-adjusting circuit electrically connected to the counter for adjusting the slice reference level, the voltage-adjusting circuit comprising:
• a first current pump for generating a first current:
• and a second current pump for generating a second current, wherein a first offset value and a second offset value are set according to the first current and the second current, and the voltage-adjusting circuit is configured to increase the slice reference level by the first offset value when the digital sum value is larger than an upper limit, and decrease the slice reference level by the second offset value when the digital sum value is smaller than a lower limit.