Other Parts Discussed in Thread: LMZM33606, , LMZ35003
Hi
My goal is to design a on-board power supply for my application, which is a IOT SOM Computer with some peripherals. The device should be possible to power by the following input sources:
- regular dc power supply, usually 24V but should accept 20...48V
- rectifies ac from transformer (24VAC excepted about 45V DC rectified). Smoothing here is as bad as possible because of space issue, high ripple should not be a problem
- POE Converter with an output of 24VDC
Since this is a low volume project, it would be preferable to use "module" type of power converters, since they are a validated design and offer very good price to value in low volume projects, often a dcdc-converter (IC,Coil, Diode etc) in applications of 100-200 pcb's make the same price as a modules.
The power budget would be calculated as following:
SoC: 3.3V @ 4.5A = 13.7W
Peripherals: 5V @ 1A = 5W
Total: 19.85W = 20W
For the 3.3V, i need a module with around 5A of output. Most modules with high output current, are limited to a max input of 36V. So i was thinking of the following combination:
LMZM33606 - for 3.3V, 4.5A (Vin Max 36V)
LMZ36002 - for 5V, 1A (Vin Max 60V)
And to bring down the input voltage (for the LMZM33606), i would use another LMZ36002 (Vin Max 60V) to set the input for the modules above to 24V ~1A
Is this a good approach for this design? Are there any better options?
