Description
The SN71052 is a highly integrated solution for SMPS applications requiring a dual control loop to perform CV (constant voltage) and CC (constant current) regulation. The SN71052 integrates a voltage reference, Two Op-Amps (with OR-ed open-drain outputs), and a low-side current sensing circuit. The voltage reference, along with one Op-Amp, is the core of the voltage control loop; the current sensing circuit and the other Op-Amp make up the current control loop.

The external components needed to complete the two control loops are:
■ A resistor divider that senses the output of the power supply (adapter, battery charger) and fixes the voltage regulation set point at the specified value;
■ A sense resistor that feeds the current sensing circuit with a voltage proportional to the dc output current; this resistor determines the current regulation set point and must be adequately rated in terms of power dissipation;
■ Frequency compensation components (R-C networks) for both loops.

APPLICATION
◈ Battery chargers
◈ AC to DC adapters