#!/usr/bin/perl -w


use strict;
use warnings FATAL => 'all';


#
# http://www.kpsec.freeuk.com/powersup.htm
#
# Smoothing capacitor for 10% ripple,
#
#            5 * Io
#   C  =  -----------
#           Vs * f
#
# 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 UK
#


my $current = shift || die 'Missing current';
my $voltage = shift || die 'Missing voltage';

printf "\nCurrent: %2s A\nVoltage: %2s V\n\n\nApproximate 10%% ripple electrolytic capacitor value:\n\n%.1f uF\n\n",
	$current,
	$voltage,
	(5 * $current) / ($voltage * 50) * 1000000;