SEA05L

SEA05L Advanced constant voltage and constant current controller with very efficient LED pilot-lamp driver Preliminary data Features ■ Constant voltage and constant current control ■ Very efficient LED pilot-lamp driver ■ Wide operating VCC range (3.5 V - 36 V) ■ Low quiescent consumption: 250 µA ■ Voltage reference: 2.5 V ■ Voltage control loop accuracy ± 0.5% ■ Current sense threshold: 50 mV ■ Current control loop accuracy ± 4% ■ Low external component count ■ Open-drain output stage ■ SOT23-6L package Applications ■ AC-DC adapter with LED pilot-lamp ■ Battery chargers with LED pilot-lamp ■ SMPS with LED pilot-lamp Description The device is a highly integrated solution for SMPS applications, with an LED pilot-lamp requiring a dual control loop to perform CV (constant voltage) and CC (constant current) regulation. The IC allows very efficient LED pilot-lamp driving which helps to reduce the standby consumption of the SMPS. It integrates a voltage reference, two op-amps (with OR-ed open-drain outputs), a lowside current sensing circuit and an LED pilot-lamp driver pin implemented with an open-drain mosfet driven by square waveform with 12.5% duty cycle at 1 kHz that allows reducing LED consumption. SOT23-6L (plastic package) Figure 1. Block diagram 1.23 V 2.5 V + - V CC 6 50mV + - 5 3 4 2 GND 1 OSC Isense Out Vctrl LD 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...