Power supply and display apparatus having the same

A power supply system, comprising:

• a control unit, comprising:
• a detecting and converting unit that is configured to generate a detected current based on a difference between a set voltage and a voltage representative of a current flow through an energy storage member;
• wherein the detecting and converting unit comprises:
• a voltage control unit that is configured to generate a reverse voltage responsive to the set voltage and the voltage representative of the current flow through the energy storage member, a magnitude of the reverse voltage being inversely correlated with a magnitude of the voltage representative of the current flow through the energy storage member;
• and
• a voltage-current converting unit that is configured to generate the detected current responsive to the reverse voltage, a magnitude of the detected current being inversely correlated with a magnitude of the reverse voltage.