BL8503 series is a group of positive voltage output, low power consumption, low dropout voltage, three terminal regulator. It can provide 250mA output current when input / output voltage differential drops to 400mV（Vin =4.0V、Vout=3.0V）。The very low power consumption of BL8503 （Iq=3.0uA）can greatly improve natural life of batteries. BL8503 can provide output value in the range of 1.2V~6.0V in 0.1V steps. It also can customized on command. BL8503 includes high accuracy voltage reference, error amplifier, current limit circuit and output driver module. BL8503 has well load transient response and good temperature characteristic, which can assure the stability of chip and power system. And it uses trimming technique to guarantee output voltage accuracy within±2%. BL8503 is available in SOT-89-3、SOT- 23-3,TO-92 packages which is lead free，italso can available in these packages with lead.