I've buld a project using lm338 that will use some Amps, (I'll supply power for a Beagleboneblack, 7" Lcd by 4dsystems, and another pcb). for that, that 5Amps that lm338 can provide should be more than enough..
so I bult this following the datasheet(my schematic is attached below) to give me 5volts i need.
besides that in my project i get 12v In to output this 5V, because i need this same 12v to feed the other pcb, in parallel.
everything looks nice as my pcb is on all alone with no things attached as bbb or anything. As output i have arround 5.12V, seems nice.
But, when i attach my pcb to the lcd like a shield, the bbb start to boot up(i can see the leds), screen doesn't power up(only leds below).. after +-5 secs it suddenly power off and leds blink a little bit like the power is not enough.. i can see in the multimeter that my power is by this time sort of 3.78V and still dropping(oscope pic attached)
I've read this forum and yes, I am using heatsink and a great dissipation unit
things seems to not getting hot,
resistors used in the lm338 are not smd
maybe something missing?
what can be wrong?
thanks, in advance.
so I bult this following the datasheet(my schematic is attached below) to give me 5volts i need.
besides that in my project i get 12v In to output this 5V, because i need this same 12v to feed the other pcb, in parallel.
everything looks nice as my pcb is on all alone with no things attached as bbb or anything. As output i have arround 5.12V, seems nice.
But, when i attach my pcb to the lcd like a shield, the bbb start to boot up(i can see the leds), screen doesn't power up(only leds below).. after +-5 secs it suddenly power off and leds blink a little bit like the power is not enough.. i can see in the multimeter that my power is by this time sort of 3.78V and still dropping(oscope pic attached)
I've read this forum and yes, I am using heatsink and a great dissipation unit
things seems to not getting hot,
resistors used in the lm338 are not smd
maybe something missing?
what can be wrong?
thanks, in advance.
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