2015-07-02 05:32 AM
Hello there, thank you for taking a look at my discussion , I designed the following custom STM32F051 board circuit and before sending it for manufacture I thought like posting it here to verify if everything will work.
Here is a schematic: (I also attached the pdf for more bigger size)As you can see the circuit is relatively simple, with a voltage regulator, the stm32f051 chip and a spi 16Mb flash memory.Please let me know if I made any mistakes or is it good to go.Thank you !!
2015-07-02 06:33 AM
I'd get NRST and GND to the SWD Header
I'd have a pull up on NRST I'd have a pull down on BOOT0, or ideally a way to select it high/low I'd provide a means to connect as serial header to USART1 PA9/PA10 I'd probably consider adding pads for series/parallel resistance to the oscillator unless I'd prototyped specific components without them. Assuming you're just using USB for power2015-07-02 06:48 AM
Thank you. Precious tips , I'll apply them. I have one more question , I looked online and found services that will be manufacturing & assembling this board ( custom services) for around 300 $ (while the whole things costs about 10$)! Can't I request one to be made, for lower price from ST ?? Any alternative way ? If possible to answer.
2015-07-02 08:08 AM
ST isn't going to be interested in one-up quantities*, they sell chips not boards, they are looking for $1M-$1B customers who can design/build their own boards.
For one-up boards look at using DISCO or NUCLEO boards, they are considered throw-away boards which can easily be modified or mashed up to demonstrate or test concepts.eBay is also awash with cheap boards, if I can prototype ideas on those, again it's a lot cheaper than designing/building a custom board, and we can design a board directly into manufacture on the first pass.* I don't work of ST, but have worked in the semi industry for several decades, I understand the business drivers.2015-07-02 09:38 AM
I see your point. Again thank you for inspecting my schematic !
2015-07-05 07:22 AM
If you are still going with your own board, review Section 6.1.6 in the data sheet for the recommended Vdd and Vdda capacitors to ground.
Cheers, Hal2015-07-17 11:11 AM
Thank you for letting me know HAL. Definitely a major point !