Search found 1745 matches

by victor_pv
Fri Dec 01, 2017 9:43 pm
Forum: Projects
Topic: F405 & F411 versions of the BluePill
Replies: 490
Views: 8059

Re: F405 & F411 versions of the BluePill

Adding the lipo charger seems like a good idea, specially since you already took other measures with the LDOs to run from a battery more efficiently. If you can fit the footprints...
by victor_pv
Fri Dec 01, 2017 8:39 pm
Forum: STM32F103 Boards
Topic: Driving LED dim/glow using PWM pins and MOSFET
Replies: 11
Views: 428

Re: Driving LED dim/glow using PWM pins and MOSFET

There are 4 timers with 4 channels each. Single frequency per Timer, but each channel can have a different duty cycle as Steve pointed, so you get up to 16 different PWM duty cycles, grouped 4 by 4 in the same frequency. There is also code in another thread to do PWM by software in any port and any ...
by victor_pv
Fri Dec 01, 2017 7:27 pm
Forum: Off topic
Topic: Making your own pcb's.
Replies: 45
Views: 924

Re: F405 & F411 versions of the BluePill

Roger, this blog shows the different methods with some videos, and compares them: https://lowpowerlab.com/2015/03/27/laser-etching-smt-stencils-tutorial/ According to him the laser cut ones are the best. Obviously buying a $3000 or more cutter just for that is not worth it, that's where the siloutte...
by victor_pv
Fri Dec 01, 2017 3:17 pm
Forum: Off topic
Topic: Making your own pcb's.
Replies: 45
Views: 924

Re: F405 & F411 versions of the BluePill

Vacuum pick and place:
https://blog.ohmnilabs.com/diy-vacuum-p ... -and-place

Haven't tried to make one yet, but is on my list.
by victor_pv
Fri Dec 01, 2017 2:34 pm
Forum: Projects
Topic: F405 & F411 versions of the BluePill
Replies: 490
Views: 8059

Re: F405 & F411 versions of the BluePill

Not sure why they are so cheap, but I found 5 pcs F407VE for $13.6 i.e around $2.6 each Not sure what the catch is I noticed the same thing, it's usually about the same price as a lower spec 103VC. My wild guess is that must be the most produced part in the line. Sadly we can't fit a VET in the blu...
by victor_pv
Fri Dec 01, 2017 2:27 pm
Forum: New users MUST post here first, and let us know a bit about you and your projects
Topic: Hello from Spain
Replies: 1
Views: 69

Re: Hello from Spain

Welcome Adolfo, I'm from Spain too, although not living there. I believe there is a couple other people from Spain that have posted too.
by victor_pv
Fri Dec 01, 2017 6:01 am
Forum: Off topic
Topic: Making your own pcb's.
Replies: 45
Views: 924

Re: F405 & F411 versions of the BluePill

Hand soldering 1 may be just as long as preparing and reflowing 1, but reflowing a panel of 5 or 10 of them I think should be faster than handsoldering the same number. And for a full panel using a stencil to apply solder paste to the whole panel should cut the time too. If the BOM is not going to c...
by victor_pv
Fri Dec 01, 2017 5:24 am
Forum: Off topic
Topic: Making your own pcb's.
Replies: 45
Views: 924

Re: F405 & F411 versions of the BluePill

When you initially told about the mods other people had done to that oven, I stated looking for fans. The only type that I think would stand the head are the stove or oven fans that all metal construction. I remember I found some model in Ebay for a bit cheaper than the majority of them, but even th...
by victor_pv
Thu Nov 30, 2017 11:52 pm
Forum: Projects
Topic: F405 & F411 versions of the BluePill
Replies: 490
Views: 8059

Re: F405 & F411 versions of the BluePill

I think having just the footprints in the pcb is a good idea, as long as they fit and we dont have to leave something else out. As Roger said, I got some credit in Allpcb, and have built my own reflow oven and controller based on some open designs (code in github, but I need to publich the schematic...
by victor_pv
Thu Nov 30, 2017 4:11 pm
Forum: Ideas & suggestions
Topic: Slight optimization to libmaple analogRead()
Replies: 1
Views: 253

Re: Slight optimization to libmaple analogRead()

On all the f1 boards, it seems that every analog pin works with both ADC1 and ADC2, so one could ever so slightly optimize analogRead() not to look up the ADC device in PIN_MAP[], and just use ADC1 (which is what is listed in the PIN_MAP for every f1 board): uint16 analogRead(uint8 pin) { const uin...