#avr Logs
Jan 28 2018
#avr Calendar
03:15 AM Emil: mfw
03:19 AM Emil: "nbtaoli" brings absolutely zero results with relays ;D
03:19 AM Emil: :D*
03:33 AM polymorph: hello
03:34 AM Emil: hi
03:35 AM polymorph: What regulator do you recommend for stm32f373 from a single cell lithium battery?
03:35 AM Emil: what voltage?
03:35 AM polymorph: i am looking at a micropower LDO 3,3V/0,15A SOT23-5 now
03:35 AM Emil: bro
03:35 AM polymorph: 3-4.2V in is the full range
03:36 AM polymorph: 3V is way too low for a lithium cell
03:36 AM Emil: what's your power source?
03:36 AM antto: use a solar panel
03:36 AM Emil: single cell lithium batteries are many
03:37 AM polymorph: Emil: a single li-ion cell
03:37 AM Emil: no
03:37 AM Emil: do you mean a button coin cell
03:38 AM Emil: an actual lipo
03:38 AM Emil: or something else
03:38 AM polymorph: that is a ower source with voltage from ~3.45V to 4.2V
03:38 AM polymorph: lipo because my thing will eat like 70-140mA
03:39 AM Emil: then say 1S lipo pls :D
03:39 AM Emil: Also use a step down smps
03:40 AM Emil: well, if you are okay with 100mW waste then pretty much any 3.3v LDO will work
03:41 AM Jartza: no recharging?
03:41 AM polymorph: i also will need a micropower ldo for low power projects ;>
04:16 AM _ami_: is gain of 100 unstable in case of LM358 op-amps?
04:16 AM _ami_: i am trying add current control on those cheap buck/boost module converters (from china)
04:17 AM _ami_: i got 0.01 ohms shunt
04:17 AM _ami_: so i would like amplify voltage drop by 100 times per 0.01 v drop (on 1A current)
04:43 AM Thrashbarg: _ami_: should be fine if you decouple the power rails properly
04:44 AM _ami_: Thrashbarg: thanks,
04:45 AM _ami_: i would try the ckt now :)
04:45 AM Thrashbarg: okay
04:45 AM _ami_: differential op-amp across 0.01 shunt -> comparator -> feedback pin of XL6009. Lets see.
04:45 AM Thrashbarg: adding gain on an op-amp reduces the bandwidth
04:46 AM Thrashbarg: if it does become unstable you could try putting a 10pF capacitor in parallel with the feedback resistor
04:49 AM _ami_: got it. thanks
04:51 AM polymorph: _ami_: it works, it has a GBW of 1MHz though, s at 100 you get 10 kHz bw
05:12 AM lwlvl: I'm doing a tryout with SPI and ADC....ADC works so far, so does SPI (running as slave. the LED turns on and off), but the response-values (0xff/0xee) are not sent back to the master. https://paste.pound-python.org/show/g0NCRbyBZiJ8iETpT6Ni/
05:17 AM polymorph: _ami_: your problem will be offset, you may need to get an op07 instead and use +-9V supply
05:34 AM polymorph: can you make sense of this sentence? LP2950, LP2951, NCV2951 www. onsemi.com 6 DEFINITIONS Dropout Voltage − The input/output voltage differential at which the regulator output no longer maintains regulation against further reductions in input voltage. Measured when the output drops 100 mV below its nominal value (which is measured at 1.0 V differential), dropout voltage is affected by junction temperature, load current and minimum
05:34 AM polymorph: dick stuck in the ceiling fan situation following this explanation
05:36 AM Emil: Yes
05:38 AM polymorph: page 6 https://www.onsemi.com/pub/Collateral/LP2950-D.PDF
05:39 AM polymorph: main page says Low Input−to−Output V oltage Differential of 50 mV at 100 A and 380 mV at 100 mA - that would be ok, but 1V drop not
05:42 AM lwlvl: I'm doing a tryout with SPI and ADC....ADC works so far, so does SPI (running as slave. the LED turns on and off), but the response-values (0xff/0xee) are not sent back to the master. https://paste.pound-python.org/show/g0NCRbyBZiJ8iETpT6Ni/
06:37 AM polymorph: ok i think i have a decision, ac supply regulation: LD1117, lipo reg: LP2985IM5-3.3, MC78PC33NTRG would work too
07:55 AM polprog: polymorph: hi, yesterday i found a better rip of Arrakis -The Spice. sounds like original mix youve sent me: https://www.youtube.com/watch?v=RaTZeIYTOQM
07:56 AM polprog: gota go
08:44 AM polymorph: nah prepared 2 component epoxies
08:54 AM polymorph: 2 type, 5m/2h and 1h/24h
09:11 AM polymorph: wow the 373 has gain setting on the 16 bit adc
09:11 AM polymorph: who needs opamps lol
09:12 AM polymorph: _ami_: :) http://www.st.com/content/ccc/resource/technical/document/reference_manual/fa/06/c7/15/3b/2a/4c/f1/DM00041563.pdf/files/DM00041563.pdf/jcr:content/translations/en.DM00041563.pdf
09:12 AM polymorph: adc 0.5 - 32x gain 16 bit
09:26 AM nuxil: _ami_,
09:27 AM nuxil: watch GreatScott. https://www.youtube.com/watch?v=8uoo5pAeWZI
09:27 AM polymorph: polprog: https://www.youtube.com/watch?v=VpDmGYRiT_M
09:30 AM _ami_: yeah nuxil, inspired by this video..
09:30 AM _ami_: thanks
09:31 AM nuxil: :)
09:48 AM nuxil: i need to redesign my dds. haveing lots of irs (3xadc's)' running when timeing is crusial wasnt good. :\
09:48 AM polymorph: nuxil: what are you creating?
09:49 AM nuxil: dds
09:50 AM polymorph: 3 adcs and avr?
09:50 AM nuxil: yes. i use 3xadc. 1 for mesuring the ofset, one for mesuring peek to peek value and one for keypad.
09:51 AM polymorph: ooh
09:51 AM polymorph: your analog matrix ;>
09:53 AM nuxil: yup. so i came with an idea. offload the irc to a atiny85. use a i2c io exapander then just have 1 simple external trigger on the atmega 324 chip that does the dds.
09:53 AM nuxil: something like this. https://gyazo.com/b54f5a46c337bf55e74c284f802c44af
09:54 AM polymorph: :)
09:54 AM nuxil: it should say mcp23008. not mcp20008 :p
09:58 AM polymorph: ill stay with my 595s
09:58 AM nuxil: :)
09:58 AM nuxil: they are fun too :)
09:58 AM polymorph: they only cost 3 pins, 4th is pwm tristate
09:59 AM polymorph: you can infinitely scale it
09:59 AM polymorph: connect 128 in series
10:00 AM polymorph: it is possible to clock in data at 100MHz
10:09 AM nuxil: now i need to "modularize" my my code and move most part onto the atiny85.
10:10 AM nuxil: i hope it will fit. seen that the code i have now fill the atmega 20% around 8K. and thats the limit of the atiny.
10:36 AM polymorph: DIY printer and linear drives https://www.youtube.com/watch?v=IgU__c4NgrM haha this guy is cool
10:43 AM nuxil: 6:25 LOL
10:44 AM polprog: macgyver :P
10:44 AM polprog: i like the way how he connected the mototr to the shaft
10:45 AM nuxil: LOl his printer head haha
10:46 AM nuxil: macgyver style indeed.
10:46 AM polprog: i had this lego gear that had two parts, inner part was turned by the friction of the inner one. if the outer part of the mechanism, jammed, the inner one would keep rotating
10:46 AM polprog: haha i remember making so many different gearboxes/transmissions outta those lego technic gears
10:47 AM polprog: i think i once made a generator. like a real one
10:48 AM polprog: i made a transmission that had 1:very high ratio, spinning the spindle was causing a block of magents to rotate very fast. a coil next to it, a bridge rectifier and i think it even lit a led!
10:49 AM Tom_L: should have put them on the 1: side :D
10:49 AM Tom_L: or vise versa
10:51 AM polprog: Tom_L: can you recommend me some 2d cad program ? i need to design a shelf and i wanted to learn CAD alongside
10:51 AM polprog: i tried freecad but this whole 3d stuff overwhelmed me
10:52 AM Tom_L: i don't use the free stuff much but there are a few decent 2.5d ones out there
10:52 AM Tom_L: freecad was one i would have suggested
10:52 AM Tom_L: cambam maybe/
10:52 AM Tom_L: ?
10:53 AM Tom_L: you don't have to use the 3d part
10:53 AM polprog: i managed to design a single object in freecad, but i couldnt move it or define where i want it to be respectively to other objects.
10:53 AM polprog: tried to design an enclosure with a lid
10:53 AM Tom_L: the free ones lack decent features
10:57 AM nuxil: just use blender or other free 3d tools. design you casing there. export it as dfx/3ds/fbx or whatever. then import that to whatevercad app.
10:57 AM polymorph: [16:25] <polymorph> polprog: https://www.youtube.com/watch?v=VpDmGYRiT_M
10:57 AM polprog: i tried but keeping proper sizing in blender is hard
10:58 AM polprog: after all its for art not cad design
10:58 AM polprog: polymorph: cool tune
10:58 AM polprog: i just put it on
10:58 AM polprog: ;)
10:58 AM polymorph: Plotter made of two old CD drives, a servo and a Raspberry Pi https://www.youtube.com/watch?v=-XhMT4wXSG4
10:58 AM nuxil: use free autodesk then :p or pirate cinema4d/maya :p
10:59 AM polymorph: cost is not an argument lol
11:00 AM polprog: hmm i have many many floppy drives.. maybe i should try to make a small cnc out of them
11:00 AM polprog: even a tiny plotter would be nice
11:14 AM polymorph: btw oldlaserjet can print on sandpaper lel https://www.youtube.com/watch?v=uLboQiTNGI0
11:16 AM Thrashbarg: but for how long...
11:16 AM polymorph: at least 1 :)
11:31 AM Thrashbarg: needs more coffee
11:31 AM * polprog pours a big Americano into the printer
11:36 AM Thrashbarg: heh
11:38 AM polprog: i have to go to school tomorrow
11:38 AM polprog: fuck
11:41 AM polymorph: bring it home
12:55 PM polprog: polymorph: https://www.youtube.com/watch?v=tMUS3WJ_K58
12:56 PM polymorph: polprog: https://www.youtube.com/watch?v=ZFmC7hd1hno
12:59 PM polprog: oh yeah i know those :P
12:59 PM polymorph: https://www.youtube.com/watch?v=GNTtR6ZpUOo
01:00 PM polymorph: hahaha
01:00 PM polprog: i found the original video on youtube, the guy's named Pawel Zadrozniak. found his blog, thats how i learnt about avr
01:01 PM polprog: this guy is cool too: https://www.youtube.com/watch?v=w68qZ8JvBds
02:02 PM nuxil: polprog, https://www.youtube.com/watch?v=39YUvCqxPSs :
02:04 PM polprog: 3:48 i always wanted to use a keyboard like this
02:05 PM polprog: last one is the best
02:06 PM nuxil: :)
02:06 PM polprog: plus, this is the first thing i'll do when i i get around to pwm-ing stuff
02:07 PM polprog: http://joemonster.org/mg/154143,16
02:07 PM nuxil: heh
02:07 PM polprog: https://www.youtube.com/watch?v=2xZfTcrq8nA
02:10 PM polymorph: polprog: you meant dac right?
02:10 PM polprog: yeah, dac by low-passing pwm
02:10 PM polymorph: you are not on arm yet?
02:10 PM polprog: guess waht
02:11 PM polprog: sitll waiting for the bloody parcel
02:11 PM nohit: that is a great song
02:14 PM nohit: oh there's 303 in the end :D
02:15 PM polprog: what else for acid bass ?
02:18 PM polprog: this is a classic song: https://www.youtube.com/watch?v=UO2sYTkFB0k
02:22 PM polprog: polymorph: this was my favourite thing about the intercoms in poland : https://www.youtube.com/watch?v=YGfaUyzZKqs
04:35 PM HelloShitty: Guys hello
04:35 PM HelloShitty: I need some help
04:35 PM HelloShitty: I have exam tomorrow
04:35 PM HelloShitty: I need help to answer 1 or 2 quesitons
04:35 PM HelloShitty: about Power Electornics
04:35 PM HelloShitty: Anyone around?
04:39 PM LeoNerd: Best just to ask your question, than ask to ask it
04:40 PM LeoNerd: .. also if it's not AVR-related you might also try ##electronics
04:40 PM HelloShitty: ok
04:40 PM HelloShitty: In an tri-phase rectifier
04:41 PM HelloShitty: if one of the three phase voltages fail, what is the impact on the average value and on the ripple of the output voltage?
04:42 PM HelloShitty: this is a fully controlled tri-phase rectifier
05:47 PM cehteh: not exptert, but isnt it oblivious that every third peak is missing, which means you get a lot more ripple as low as the cross point of the remaining phases
05:48 PM cehteh: https://de.wikipedia.org/wiki/Datei:DC_voltage_profile_of_B6_three-phase_full-wave_rectifier.jpg
05:58 PM christner: for the atmega328p, would anyone expect me to get any unexpected behavior if I leave aref floating rather than coupling it to ground?
06:00 PM polymorph: configure it, you dont connect it to gnd.
06:00 PM polymorph: lel
06:00 PM polymorph: it has internal 1V2 reference that you can use btw
06:01 PM polymorph: or it can use the Vcc
06:01 PM christner: couple it, not connect it, for hardware layout
06:02 PM christner: I don't need it for what I'm doing, I just want to make sure noise on the line isn't going to cause any trouble. seems unlikely to.
06:03 PM polymorph: ref is internally connected if you configure it
06:03 PM polymorph: by default, adc is disabled
06:04 PM christner: great, i'll try leaving it disabled and save myself placing a capacitor. thanks.
06:07 PM shifttymike is now known as Guest64300
10:28 PM polymorph: hii
10:28 PM polymorph: anybody in neeed of Tda7293s? http://www.st.com/content/ccc/resource/technical/document/datasheet/4f/18/a6/c8/21/33/41/8d/CD00001887.pdf/files/CD00001887.pdf/jcr:content/translations/en.CD00001887.pdf
10:40 PM nuxil: heh no not really :p
10:41 PM nuxil: i want one of these. http://hddwatches.com/ but too expensive :p
10:45 PM nuxil: polymorph, why you ask?
10:46 PM nuxil: THD =10%
10:46 PM nuxil: ewww
10:47 PM nuxil: how the hell can they call that chip HI-FI with 10% distortion.
10:59 PM polymorph: nuxil: <80W sine <0.1% thd+n
11:00 PM polymorph: nuxil: have 21x TDA7293 and 10x TDA7294 leftover unused
11:00 PM nuxil: o.O
11:00 PM polymorph: the 7293 is simply parallelable
11:01 PM nuxil: why did you order so many?
11:01 PM polymorph: was intending to build amps
11:01 PM nuxil: but?
11:02 PM polymorph: but class D shit came in and everybody just buys that cheap
11:02 PM nuxil: well. class D is shit indeed. and is mostly just used in cars.
11:02 PM polymorph: yep
11:03 PM polymorph: i have made and used a 7294 one for years
11:03 PM polymorph: it is Class AB and fet output
11:04 PM polymorph: used +-39V and it couldoutput 85W sine 1kHz with not noticable distortion
11:15 PM polymorph: [05:43] <nuxil> THD =10% - yeah that is tha bait :) 100W 10% THD, it really can only do 85W without distortion
11:16 PM polymorph: It also requires a generous sized heat-sink because it is AB Class
11:16 PM nuxil: yes.. yea i was to type its at full power. 99% of amps will make lots of distortion at max power.
11:16 PM polymorph: They shouldnt, but they do.
11:17 PM polymorph: I would set the maximum without distortion
11:23 PM polymorph: nuxil: the problem can be solved by using a limiter
11:24 PM polymorph: manufacturers will not want to add a limiter because they think trash sound quality louder whine is worth more for a consumer
11:29 PM nuxil: they can get away with it. because most people have no clue about distotion. all they see is n Watts. and you father/grandfather etc has no clue what distortion is unless they are into audio/electonics.
11:39 PM day__ is now known as day