I'm planning to use a 12v (20W) solar panel to power my Arduino Digispark. Since the Arduino doesn't need all that power, I have decided to use the remaining power to charge a USB power bank (5V 2A input). The Arduino only powers an LED ~20mA at the moment.
I came across 3 different types of cheap Chinese buck converters to convert 12V to 5V(LM2596, XL4005 and XL4015) , I do not know which one to choose and need your advice to decide which one should I buy. :confused:
Each module shows different switching frequency in their chip datasheet( I don't know anything about that ). LM2596 150KHz, XL4005 300KHz, XL4015 180KHz. Will this affect my project? Also each module has different max input current, LM2596 has 3A max and both the others have 5A max.
Also, Can these modules run without a heat sink in an enclosure without vents ( climate is tropical usually always above 30C and humidity above 70%)?