This low drop out regulator presented in this electronic schematic is a low drop out regulator with high efficiency designed for portable applications like : cellular telephones , handheld equipment and other portable equipments .
This low drop out regulator circuit use the ADP3367 which is a low drop out high precision voltage regulator that can supply up to 300 mA output current.
Using the ADP3367 voltage regulator we can make a fixed +5 volts power supply without other external components .
Using two external resistors we can adjust the output voltage of power supply from +1.3 V to +16 V .
Fixed or adjustable mode can be selected via the SET input pin .
The ADP3367 accept a wide input voltage range from 2.5 V to 16.5 V .
The ADP3367 is to pin-compatible replacement with the MAX667 low dropout voltage regulator .
Main features of the ADP3367 voltage regulator are : Low Dropout, Low Power CMOS, Shutdown Mode: 0.2 mA Quiescent Current , 300 mA Output Current Guaranteed , Pin Compatible with MAX667 , Stable with 10 mF Load Capacitor , +2.5 V to +16.5 V Operating Range , Low Battery Detector , Fixed +5 V or Adjustable Output .
If we want to use another voltage than 5 volts we need to calculate the value of the resistors R1 and R2 .
To choose the value of resistors we can use these formula or we can chose a value for R1 and then calculate the R2 value ( the Vset value is 1.255volts ) .