Silvia,
This is for MCU, LCD, LED (Circle), power supply.
MCU + LCD --> 270mA
LED --> 20mA typical.
300mA max is OK.
What is need by smoothing capacitor for 10% ripple,
C = (5 * Io) / (Vs x F)
Where:
C = smoothing capacitance in farads (F)
Io = output current from the supply in amps (A)
Vs = supply voltage in volts (V), this is the peak value of the unsmoothed DC
f = frequency of the AC supply in hertz (Hz), 50Hz in the HK
Subsitute :
C = (5 * 0.3) / (9.33 * 50)
C = 3215uF. therefore choose 3300uF.
This is why I choose for 3300uF. Everything should have thoery and calculation support.
For the digital application, you can choose Rubycon MBZ series or Sanyo OS-CON for computer power supply.
Those components can be supplied by hififever if you need.
Any problem, please let me know. |