A good power supply project
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Omega2+ side:
Gnd and 3v3 pins are connected thru wire-wrap IC socket pins.
330uFD 10V capacitor is used.
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@ccs-hello
What is the SMD marking code of the TD6817 chip please?
And of the TD6811 chip (the PSU of the Expansion Dock)?Thank you in advance for your answer,
gf.
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SY8009B: CU0FA
TD6817: TD6817
LM3671: SJEB
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I would like to power the omega2 directly without a board. I understand it needs 3.3v input, of which there are no standard ones to purchase.
Would I just be able to use a standard usb cable (5V) w/ this 3.3v downstep from Banggood (https://goo.gl/zeb2eJ) to directly power the omega2?
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Never mind. Answered my own question: https://docs.onion.io/omega2-docs/hardware-prep-no-dock.html
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the TD6817 datasheet lists output @ 1.5v or 1.8v so i'm a bit lost in understanding how it can power the Omega2+.
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@Douglas-Kryder
TD6817
Output Voltage Programming
In the adjustable version, the output voltage is set by a resistive divider according to the following formula:For example:
Vout= 0.6 * ( 1 + R2 / R1 ) = 0.6 * (1 + 680k / 150k) = 3.32V nom
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Make sure getting the TD6817 (with the blank suffix)
not part such as TD6817-1.8 (which is a fixed voltage part.)TD6817 (without suffix) is an adjustable voltage buck regulator which is what we need.
ccs_hello
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yes, i know how to search. the problem is in the usa there are not any hits that offer this td6817 as you describe. it is 100% full moon tonight so i'm gonna wait a few days and try it again. after 22 years exposure to seach on internet i know when to fold and walk away. it is an interesting build, though. thank you for that!
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Try Aliexpress
lm3671mf-3.3 (or LM3671 module) is easier to find. Circuit is simpler but it costs more.
