Other Parts Discussed in Thread: LMR14010A, LMR33610, LMR36510, LMR36520
Hi,
we have a complete line of transmitters (pressure, humidity, temperature, CO and CO2). Now we're implementing Wifi option, 350mA peak, in out product line.
As we would have a max current of 450mA (100mA peak from CO2 and 350mA from wifi), i'm testing some regulators for that situation. From most of the time this circuit will consume ~160mA.
Out first bet was a regulator from another brand, due to it's small footprint, BD9G101G, i burnt around 30 units, tried even a small heat sink, and 2 designs, and then gave up.
As we already worked with LM2574 in our previous design, we tried it. We were not doubting it would work, so we manage to fit in our new PCB, and with the finished project i tried make it work with 450mA, and it burned.
It heats a lot with 300mA, but it's been turned on for a while, and maybe the RMS value would be always bellow 300mA (need to make some more tests with the Wifi). But it's capacitors has a lot of heat too, so i'm concerned that it would drop a lot the life of the product.
Anyway, how does this regulators are tested for 500mA? With an infinite heat sink? I'm using the datasheet's design, for fixed 5V, 330uH.
Should i use a higher current reg. even knowing i have only some peaks near the maximum regulator working range? The heating is a problem for me beacause of the temperature sensor, can you indicate other regulator, with less heat, small footprint, low cost?