How can the R1501S120B-E2-FE (IC REG LINEAR 12V 1A 6HSOP) voltage regulator be rated at 1 amp when the max power dissipation is 1700mW? That makes it a 140mA regulator.
Welcome to the Technical Forum. The power dissipation of a voltage regulator is the difference between the input and output voltage. This would not be the same as the total wattage . You can see the charts for output voltage and current at different input voltages starting on page 10 of the data sheet. Here is the link from the website: https://www.nisshinbo-microdevices.co.jp/en/pdf/datasheet/r1501-ea.pdf
Power Dissipation is reflected as the formula
(Voltage_In - Voltage_Out) x Current_Out
It’s a way to reflect how the greater the voltage input is than the voltage out of a regulator the less it is able to produce the part’s specified maximum current output.
1700mW would be (13.7Vin - 12Vout) x 1A
Which means going by that formula (16Vin - 12Vout) x 425mA would give you 1700mW
The closer the input voltage is to maximum input voltage the less current you can expect the voltage regulator to be able to put out. An increase in ambient temperature also derates this specification.
You can increase the 1700mW to a higher wattage if you go with a 4 layer board with a lot of copper dedicated to thermal transfer. Page 25 of the datasheet goes over how board layout plays into consideration.
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