The Texas Buck driver series, Q8 / Skyray King 2S/4S buck driver RELEASED!

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DB Custom
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We used to have Scaru breaking new ground with multi emitters before anyone else did it, ChicagoX was making big lights, light bars, designing boards, way back before FET drivers. OL was building MagLites, filing his mark on the tubes and random finishes. The forum has changed a LOT since I came in over 3 years ago. We’ve lost a lot of good folks too. Foy used to be hilarious withhiswayofrunningwordstogethersigningoff. Some of the big group buys brought a lot of people in from other sites, which changed the face of this forum as well.

Now The Miller is breaking new ground, as is TomE and Pilotdog68. I’m still just a hack slamming lights together to find out what they do before the magic smoke appears…

Flintrock
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Yeah, I get it.  It works and stuck.  Again, not criticicizing, just like to understand what's needed and what is just established and why.  After all we are making some changes anyway probably, particularly the ldo voltage, so I can't just assume that  won't have any effects.    Now though I know, we aren't referencing of LDO (but I think not 1.1 either).

 

22 is a bit different from 19.1 (about 15% different OTC times).  My point was more why not 20. I suppose people will need to order an LM3409 anyway, so adding a non-standard resistor value to the order doesn't really matter in the end.  It's just a funny number.  That's all, especially since almost all the rest are standard values.

 

At TA, yeah,  1.1  won't work without much higher resistance values than we're discussing.  2.55V (2.56 I think but  whatever) is right as DB says (thanks for that feedback DB), and anyway, yeah, it's not vcc so that's the main thing because that's what I changed and wanted to make sure wouldn't impact anything.  So 36K has worked and we'll use it.

 

 

HarleyQuin
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Just for the record,
22k was introduced when driver boards were created where R1 was changed to a position before the diode D1. This allowed for more precise voltage measuring (while introducing OTC timing problems…).
22k instead of 19k1 compensated for the loss of the ~0.25V drop over D1, so existing firmware (mainly STAR back then) could be used on these newer drivers while maintaining the same LVP voltages.
Those were the days… Smile

Oshpark Boards:
HQ ProgKey: Universal Driver Programming Key . Boost: HQ 15mm/17mm programmable boost driver with ATtiny13A
46mm Triple-Channel: BLF SRK FET v3 . 17mm Linear: HQ10D / HQ4D / HQ4S . Contact Boards: 22/24/26mm

Flintrock
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You make me feel pretty old talking as if 3 years ago was a long time.  But it was a bunch of work put in  clearly.

HarleyQuin
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Flintrock wrote:

You make me feel pretty old talking as if 3 years ago was a long time.  But it was a bunch of work put in  clearly.


Yes, and it was a lot of try and error, some dead ends… and a lot of fun. Just like today, really. Smile
It’s just that in these years BLF as a whole has developed an incredible base of hardware and firmware. And it still moves on.

Oshpark Boards:
HQ ProgKey: Universal Driver Programming Key . Boost: HQ 15mm/17mm programmable boost driver with ATtiny13A
46mm Triple-Channel: BLF SRK FET v3 . 17mm Linear: HQ10D / HQ4D / HQ4S . Contact Boards: 22/24/26mm

Flintrock
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To me some weird historical baggage is how the E48 and E96 series don't include the E24.  Sure you can get 2% spacing with fewer resistors by starting over, but then you still ALSO need the E24 resistor values on hand anyway(if you want to be stocked up), so it's actually more in the end.  I suppose it makes sure nobody accidentally uses 10% resistors when 1% is needed. In practice it doesn't really work out that way since 1% tolerance E12/24 values still get used at least as often as not, probably because people don't have to look them up.   How often do you see a 1% 47.5 specced? Probably almost as often as a 48.7, but not nearly as often as a 47.0.

DB Custom
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Wow! What did I say in here that earned me a rude mark?

Flintrock
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It certainly wasn't me.. or not unless I clicked something by accident (that could be possible).  Anyway, we're cool as far as I know.  

DavidEF
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DB Custom wrote:
Wow! What did I say in here that earned me a rude mark?

WHAT? Shocked Sad Facepalm

The Cycle of Goodness: “No one prospers without rendering benefit to others”
- The YKK Philosophy

Flintrock
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So about C1,  it turns out it does want to be bigger, for the same reason many of the caps do, 4S, high voltage.  I forgot that C1 is full voltage.  In 0805  10uF ceramic or Ta, there are no x7R caps over 16V on digikey at least.  Best I can do is a $0.57 cent 25V X7S ceramic.  That should  probably work for such a light load, on the other hand the cap is right next to the inductor pad.   The 1206's are $0.20 in bulk, and basically one more is free if only making one driver anyway.   So yeah, we can probably make due with an 0805, but ideally, it's specced as 1206. 

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DB Custom wrote:
Wow! What did I say in here that earned me a rude mark?

I am not sure what all the rude clicking is about. The only one I have got was a post that everyone agreed was not rude. I just ignored it as someone having a bad day.

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Flintrock wrote:

So about C1,  it turns out it does want to be bigger, for the same reason many of the caps do, 4S, high voltage.  I forgot that C1 is full voltage.  In 0805  10uF ceramic or Ta, there are no x7R caps over 16V on digikey at least.  Best I can do is a $0.57 cent 25V X7S ceramic.  That should  probably work for such a light load, on the other hand the cap is right next to the inductor pad.   The 1206’s are $0.20 in bulk, and basically one more is free if only making one driver anyway.   So yeah, we can probably make due with an 0805, but ideally, it’s specced as 1206. 

I will see what I can do when I rearrange things. I would not hold out high hopes though, it is really tight over there and DEL likes to see the traces as short as possible for all the MCU power leads.

Flintrock
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Got the shopping cart almost done.  This is going to be expensive.  Heck it might be more fun designing it than buying it.  ..yeah, looking like about $22 plus the board of course.  Ouch.

Texas_Ace
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Yeah, I kinda got that sense fairly early on. Glad to have it as an option but not real practical to actually use for most lights.

This is why I have been reconsidering making an op-amp driver. Not as efficient but a heck of a lot simpler, easier and cheaper.

I just have not had a lot of luck picking out an actual op-amp IC with which to start such a build.

Flintrock
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Oh as for rude.. the button is right next to reply.  I suspect that's the main cause.  The op amp sounds good.  It's the middle modes that are hard to get well with anything, and those are the modes I like.

Texas_Ace
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Flintrock wrote:

Oh as for rude.. the button is right next to reply.  I suspect that’s the main cause.  The op amp sounds good.  It’s the middle modes that are hard to get well with anything, and those are the modes I like.

Yeah, I figure the middle modes could be sorted out with a combo of pwm and resistance to keep heat under control for the higher powered setups.

DB Custom
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In the grand scheme of things, spending $25 on a very advanced driver isn’t bad at all. Ok, so it’s not cheap, but what is these days and still holds value? So if we’re building a nice big light, it’s an essential qualifier for ultimate success. I don’t mind paying it, not every light would get a driver like this so it would remain a special build and would show the effort.

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Texas_Ace wrote:
The 19.1x vs 22k doesn’t make a big difference but it is noticeable as about an extra .5-1 second for the long click to activate. It can be recalibrated for the 22k naturally but it ends up right at the very edge of the range.

19.1k puts it closer to the upper middle of the range which is nicer to work with.


That’s one thing I’ve not understood fully… When the MCU is shut down, the OTC get’s discharged through the voltage divider? That means that the two separate pins are internally connected when the MCU is off?
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Mike C wrote:
That’s one thing I’ve not understood fully… When the MCU is turned off, the OTC get’s discharged through the voltage divider? That means that the two separate pins are internally connected when the MCU is off?

I don’t understand it either but I have seen the effects first hand. Normal OTC calibration settings are in the high 100’s with the 19.1k but with the 22k resistor I had to bump it up to right at the limit of ~240 or so and it proved to be not as consistent in my testing. So I went back to 19.1k myself.

22k works fine, just more of a hassle to calibrate.

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I’ve seen many report it so I don’t doubt it it all. I’d just like to understand why. Once I get home I’ll measure resistance over the pins on a MCU that isn’t connected to anything.

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Please do report your findings. I never cared enough to actually figure out the reason why myself.

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Mike C wrote:
Texas_Ace wrote:
The 19.1x vs 22k doesn't make a big difference but it is noticeable as about an extra .5-1 second for the long click to activate. It can be recalibrated for the 22k naturally but it ends up right at the very edge of the range. 19.1k puts it closer to the upper middle of the range which is nicer to work with.
That's one thing I've not understood fully... When the MCU is shut down, the OTC get's discharged through the voltage divider? That means that the two separate pins are internally connected when the MCU is off?

 

 Sometimes when you think you understand something is when you haven't thought about it enough (referring to myself).  I had missed a couple of details here at least.

Update: yeah, I was definitely confused.  The rest of this is just silly, well except for the bit about the zener voltage sensing:

 

The zener situation is probably quite a bit different than the LDO situation.  In either case though when ground is disconnected the mcu should continue to run powered by the cap(edit: I really was thinking about C1 here confusing it with OTC).  The current draw on it is I guess 10x higher than the divider current so it runs fast until it reaches shutdown voltage in zener case or the ldo reaches its dropout limit in the ldo case.  But this is fast compared to the divider RC anyway so doesn't contribute a significant lag.  Obviously it impacts the t=0 cap voltage.

 

In the zener case I hadn't appreciated that the cap ) stays only at zener voltage (plus or minus the input diode vf) according to this diagram anyway:

http://budgetlightforum.com/node/48447

 

In the LDO case it stays higher and for voltage monitoring while on that matters, but when turned off it still should drain down to a pretty similar level, but the voltage of the LDO should have a big impact on OTC timing I think, because it determines what voltage the cap is left at when it drops out. It seems this has to be higher for LDO than for zener so maybe there's some confusion comparing OTC when there's two different situations.

I assume the LDO and mcu shutdown with high resistance between vin/vcc and ground, but maybe that's different for the two cases also.

 

Now what I really don't get is the turn on.  In either case if the mcu/ldo has enough voltage to turn back on, the cap must have already charged back up no? And always to the same level.  So what's left to measure?  It seems to me almost like a resistor is missing between the R5/R1 juncion and the cap (or between the cap and ground).  Shouldn't the cap charging lag behind Vcc if the cap level is to be detectable? Maybe that would help with some of these "stability" issues?  Obviously it works, and I'm still missing something.  Still maybe it works for reasons that aren't well controlled?  Or more likely it's just me.

 

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As for price, yeah. we're talking $22 PLUS the board.  What do these board run?  $20 for three?  Which is still $20 if you only need one.  Still, yeah, the big brand lights are expensive too.  Maybe folks will find ways to shave a few $.  The first folks to try it better know they're taking a gamble though and just be in it "for science".  I certainly make no guarantees on my part.  You're lucky if this thing doesn't burn your house down.

   

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Yeah, the boards will be about $15-20 depending on where you get them. Might get them a little cheaper from china.

So basically it will cost as much as the Q8 to upgrade the driver lol.

Hence why I am thinking about giving an op-amp a go after this one is done.

Flintrock
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Here goes.  Hopefully I didn't mess anything up.  Your risk, not mine.  Only buy and build what YOU want.  I have nothing to do with it. Smile

 

Parts list for 16.8V input, 12V nominal output, driving 4p xhp-35 at 2.5A per LED, 576 khz, 10A total (can go higher, but it’s an experimental driver)

 

The Parts

 (see shopping list below if impatient)

 

MCU: Attiny85 the normal one, attiny85-20SUR I believe is usually fine.  V version is also fine I think. (However if driving with 4.2V an attiny85V should probably be used because this driver presently requires an LDO  for the mcu even for 1S batteries and the LDO will need to operate below the lowest battery level, needs more thought though and wil require some resistor value changes)

 

LDO: MIC5235  3.0V (other voltages CAN work, but require some resistor value changes)

Buck IC: LM3409  10-MSOP-PowerPad (or EP)

Inductor, must be 17.15*17.15mm or very close. 10uH absolute minimum inductance.  30mohm max resistance. 

Vishay IHLP6767GZER150M11 is a good choice since resistance matters most.  It's very expensive though, $6!!, but other alternatives are about the same.

 

Diode, "8PowerTDFN" (might be compatible with similarly named footprints?)  STPS30M60DJF-TR has a low 0.5V Vf and low leakage current when hot. 

 

Mosfet:

Powerflat 5x6 p-channel FET (PFET), Infineon BSC084P03NS3 G  Balances low Rdson with low gate capacitance. Gate charge divided by voltage should be less than ~12nF at worst. Half that is better. Rds on should probably be less than 20mOhm at worst.  Low Rdson is good for high power.  Low gate charge is good for low-current efficiency.  It's usually some tradeoff.

 

Caps:

 

C2 10.uF 0805, Vcc bypass 4V minimum, 6.3V or more highly preferred,  10%  

Cf 1uF 0603, Gate drive bypass, 16V 10%

C1 10uF 1206 , LDO input bypass, 35V 10% 

Cf2 10uF 1206, Iadj voltage filter,  4V minimum (6.3 preferred). 10%, x7r preferred  but 125C rated should do.        Alternative: 220uF for soft mode transitions. Tantalum and high ESR (ohms even) are OK here.

Cin  10uF 1206 or 1210,  Input cap,  35V 10%, two minimum, 3 x 1206’s should fit.  4 might fit and is even better. <20% dissipation factor at 1Mhz, 10% prefered.

Co  10uF 1206 or 1210, Output cap,  35V 10% One is enough but two is insurance.  <10% dissipation factor (5 is better), with good performance up to 1Mhz.  

          Just buy ten of 1206 10 uF caps and you’re set.  Cin and Co should be high quality caps.

 

Coff   470pf 0603 35V  Buck off-time cap.

All caps should be ceramic unless stated, X7R or better strongly preferred (125C or higher rated) .

 

 

Resistors:

R1 220k 0603 for e-switch 22k for clicky maybe.   (with OTC mods now under development, the clicky issue will dissappear)

R2 12k 0603 for e-switch, 1.2k for clicky maybe.

R5 4.7 ohm 0603 1/8 to 1/4 watt might be wise here, but 1/10 should be ok I think.

BR  This has no purpose on this light.  You can use the pads to get voltage for wiring something.

Rf2 3.9K 0603  

Rf3 2.7K   0603 (Could use 4.7k and 3.3k also for a little softer mode transitions with the 220uF cap)

Roff  4.7k 0603 with the 470pf Cf, this will give very roughly 580 khz, which seems ok.

Rsense, 2512, current sense resistors, X 3. 0.074 ohm each, 2W rated, adjusted for max current, see below.

Ruv2,  any value,  0-ohm is even ok.  4.7k is also fine for example

Ruv1,  leave off.

All resistors should be 1% tolerance, rated for high temperature, 155C preferred, 1/10 W or more unless specified

 

Jumpers

You will need to jumper the battery pad to 4S for this setup.  That requires 1 jumper.  To my surprise most SMD jumpers are specced only at <50ohm.  Vishay has some in 1218 and 2010 rated to < 4 or 5 mohms and 12 to 20 A for about $0.50 cents each.  Personally, I'd just use some solid copper wire.

 

 Adjustments

 

RSense

Max current occurs  at 0.248V drop across Rsense.

So Rsense_total=0.248/Imax.

But there are three resistors, so if they are the same, they should each be:

Rses1=3*0.248/Imax.  Err on the high side of resistance values to be safe.

But no software adjustment can ever make the current higher than the max value set here.

 

Ex:  2.5A for xph35*4= 10A total.

Rses= 3*0.248/10=0.074 , closest match, 0.075 ok.

 

Soft mode transitions:

To achieve slow (~0.33 s RC) you can use a Cf2 of 220uF and adjust speed by increasing or decreasing Rf2 and Rf3.  Some options are:

Rf2: 3.9K,  Rf3: 2.7K (flintrock's favorite)  ~0.35s RC time

Rf2 4.7K,  Rf3 3.3K  ~.43s RC time  requires one less new value.  Much larger and the current control circuit gets an offset, but it should be < 0.7% offset with these values still.  Twice as high could still be ok but I think these RC values should feel nice.  PWM will be used to get lowest modes anyway so a small control offset is ok.

These are chosen to prioritize standard resistor values, but either matches the max control voltage to better than 1.2% after bias current correction.   For best precision you can use a 1.02K and a 715ohm, but won’t get very soft mode transitions and probably won’t notice the precision improvement.  If you’re using a 10uF cap anyway, then you can as well use these lower resistor values.

 

 

Expert tuning: 

Roff:

In brief, increasing Roff decreases buck frequency, nearly proportionally, and of course decreasing Roff increases frequency.  You can vary it by about twice in either direction.  Higher frequency uses more switching power which is important for low power modes, however lower frequency has more ripple current which also impacts low power modes.  For middle modes, low frequency is best.  For lowest modes, it's not clear yet (maybe never will be).

 

The frequency of the buck is determined by the offtime and the duty cycle.  The duty cycle is approximately Vo/Vin.  The off time is given by equation 4 in the manual:

http://www.ti.com/lit/ds/symlink/lm3409-q1.pdf

or approximated by equation 6 (might as well use 4).

The frequency is (1-Vo/Vin)/t_off.   As Vin gets very close to Vo this approaches 0 frequency, so as you near direct drive for low batteries or high current, the buck just stays on. For 16.8V in and 12 to 13V out, a good frequency target is probably around 500khz.

 

Iadj:

Rf2, Rf3, Cf2, LDO voltage, and a pwm duty cycle all determine the current set point. This set point is controlled by a voltage intput to the IC and you can read about how that's achieved here:

http://budgetlightforum.com/node/50413

Only duty cycle should really need to be adjusted though (through software modes) for current control.  Max current is adjusted with the sense resistor, not with this.  Of course software could limit the duty cycle, but that’s not the safest approach to limiting current.

 

 

LM3409 low voltage shutoff

Ruv1, Ruv2 are the voltage divider for buck IC shutoff.  This is redundant with MCU shutoff.  You can leave off Ruv1 entirely and use pretty much any value at all for Ruv2 then. This will disable this feature.  

 

If you want to use this feature,  there are two concerns, the cuttoff value and the hysteresis.  If the IC cuts off at 2.7V but the unloaded battery voltage recovers to 3.1V and the hysteresis is only 0.1V, it will immediately turn back on because the IC is still powered.  There is no mechanism to interface this with software to lock out or lower the mode, so it will probably flicker on and off.  Best is probably to have very large hysteresis.  Presumably a power cycle will reset the hysteresis and mode programming that starts in low modes could allow the light to be turned back on at lower power, so the best solution is probably to use a large hysteresis.  Hysteresisis in volts per cell h is:

h=.000011*V*Ruv2

Then

Ruv1=1.24*Ruv2/(Voff-1.24)

So a 110k Ruv2 would give 1.2V/cell hysteresis, should be enough, and pairs well with a 33k Ruv1 for a 2.7V cuttoff, 36k for 2.5V, or 30k for 2.9V.  These are not included in the default shopping list.  The default shopping list leaves this feature disabled.

 

 

Shopping list

Digikey carts will apparently expire and they only work on digikey.

 This is better:

 

References   Quantity   digikey   Description  
U1   1   ATTINY85-20SURCT-ND   IC MCU 8BIT 8KB FLASH 8SOIC  
LDO   1   576-2783-1-ND   IC REG LDO 3V 0.15A SOT23-5  
U2   1   LM3409MY/NOPBCT-ND   IC LED DRIVER CTRLR DIM 10MSOP  
L1   1   541-1287-1-ND   FIXED IND 15UH 14A 14.4 MOHM SMD  
D1   1   497-12421-1-ND   DIODE SCHOTTKY 60V 30A POWERFLAT  
Q1   1   BSC084P03NS3 GCT-ND    MOSFET P-CH 30V 14.9A TDSON-8  
C2   10   1276-2872-1-ND   CAP CER 10UF 16V X7R 0805  
Cf   1   311-1446-1-ND   CAP CER 1UF 16V X7R 0603  
Cf2,Cin,Co,C1   10   1276-6767-1-ND   CAP CER 10UF 50V X7R 1206  
Cf2 alternate   1   490-13970-1-ND   CAP CER 220UF 6.3V X5R 1206  
Coff   10   1276-1094-1-ND   CAP CER 470PF 50V X7R 0603  
R1   10   311-220KHRCT-ND   RES SMD 220K OHM 1% 1/10W 0603  
R2   10   311-12.0KHRCT-ND   RES SMD 12K OHM 1% 1/10W 0603  
Roff, Ruv1   10   311-4.70KHRCT-ND   RES SMD 4.7K OHM 1% 1/10W 0603  
R5   10   RNCP0603FTD4R70CT-ND   RES SMD 4.7 OHM 1% 1/8W 060  
Rf2   10   311-3.90KHRCT-ND   RES SMD 3.9K OHM 1% 1/10W 0603  
Rf3   10   311-2.70KHRCT-ND   RES SMD 2.7K OHM 1% 1/10W 0603  
Rsns   3   696-1670-1-ND   RES SMD 0.075 OHM 1% 2W 2512  

See section above about the battery contact jumper, not listed in this table. 

 

The 10 uf 1206 Ci Co caps keep going on backorder.  That's because they are cheap and seem to be really nice caps.

These are an alternative, at twice the price, and slightly worse ESR, but still good and maybe available much faster: 1276-3103-1-ND, or 1276-3102-1-ND


 

USING THE SHOPPING LIST:

You can install

https://1clickbom.com/  in firefox (doesn't work as well in chrome)

And cut the table above and hit paste in the browser tool, and "complete" (hit complete several times actually, waiting for it to update between each, seems to help) to get shopping carts at all digikey, mouser, Newark, Farnell, (no arrow :() .. Click the add to cart icon on each to automatically create a shopping cart on any of them.  Click "copy" and you get a table with part numbers from all of them.  It's pretty nice actually.  Of course a few parts are missing at mouser etc because these were chosen at digikey.

 

 

Updates, changed C2 to 10uf  and now 0805, as needed for LDO.  Chanted R1 and R2 to work with 1.1V reference as now standard in bistro.

-Removed JMP from cart, added Jumper section for battery jumper explanation.

-Updated description of BR in line with this board.

Flintrock
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Most of those resistors are chosen as the cheapest, not the best. You can get lower temperature coefficients for a price. TA says many of the big parts are also maybe cheaper on Mouser.  I think that was arrow.  Anyway, mouser is actually a few cents more.

DB Custom
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Location: Heart of Texas

Like buying a Corvette and going to Discount tire for the 4 for $99 special when you need tires… Why are those the cheapest resistors? I plan to build this driver, I don’t want the cheapest, I want the best or it isn’t worth the time y’all have spent sorting all this out.

Flintrock
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Nah, it's more like getting it with stock tires actually.  These are all 100ppm/C   which is quite good actually.  For 100C delta (so up to 125C absolute) that means 1% change, so at most you're at 2% total off the nominal value then.  Yes for 2 resistors that could  be read as 4% total, but it's not since the thermal coefficient isn't random, and both heat up the same way. 

In fact though  having two in every divider means it's almost no effect at all since they both change in the same direction.  This won't hurt performance.  The worst it will do is mean your max mode 0.5% different than what you think, as if it will really be that close even if we did use 0.1% resistors.  Of course you can order what you want, but I think these are actually the most sensible.  Anything more is probably like probably like buying gold plated fuses for the AC input to your audio amp.

 

I suppose I might not have been careful to match brands for dividers.  I probably could do that at least.  I'll give it a look when I get a chance.

Mike C
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I measured resistance from PBx pins to both VCC and GND on an unconnected MCU. I got varying results but the lowest was in the 4 to 5 mega ohms range. Things are probably different when it’s mounted on a driver.

Flintrock wrote:
The zener situation is probably quite a bit different than the LDO situation.  In either case though when ground is disconnected the mcu should continue to run powered by the cap.  The current draw on it is I guess 10x higher than the divider current so it runs fast until it reaches shutdown voltage in zener case or the ldo reaches its dropout limit in the ldo case.  But this is fast compared to the divider RC anyway so doesn’t contribute a significant lag.  Obviously it impacts the t=0 cap voltage.

 

In the zener case I hadn’t appreciated that the cap stays only at zener voltage (plus or minus the input diode vf) according to this diagram anyway:

I didn’t think about the zener case either. In any case I’d guess that a driver with the LDO solution would provide more stable readings than one with the zener solution, or at least differently. The zener does what it does, it’s passive, but the output pin of the LDO probably behaves differently when there is no input voltage.

Flintrock wrote:
Now what I really don’t get is the turn on.  In either case if the mcu/ldo has enough voltage to turn back on, the cap must have already charged back up no?

The off time cap is measured before it gets any voltage. The cap doesn’t get charged until the pin it sits on is set to output high in the firmware, at least this is the normal method in “standard” driver designs if things haven’t changed lately.
Flintrock
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Updated cart above.  To give an idea how powerful that browser tool I linked is.. it generated this for me from my table above, and populated my shopping carts for all of them:

(NOTE THIS IS NOW DEMONSTRATION ONLY, NOT CORRECT COMPONENTS)

References Qty Description Manufacturer MPN Manufacturer MPN Digikey Mouser RS Newark Farnell
U1 1 IC MCU 8BIT 8KB FLASH 8SOIC Atmel ATTINY85-20SUR     ATTINY85-20SURCT-ND 556ATTINY8520SUR   68T3811  
LDO 1 IC REG LDO 3V 0.15A SOT23-5 Microchip MIC5235-3.0YM5-TR     576-2783-1-ND 998MIC52353.0YM5TR   71Y1742  
U2 1 IC LED DRIVER CTRLR DIM 10MSOP Texas Instruments LM3409MY/NOPB     LM3409MY/NOPBCT-ND 926LM3409MY/NOPB 7615678 14R4586 1735797
L1 1 FIXED IND 15UH 14A 14.4 MOHM SMD Vishay Dale IHLP6767GZER150M11     541-1287-1-ND 70IHLP6767GZER150M1 7487615 13T1269 1845594
D1 1 DIODE SCHOTTKY 60V 30A POWERFLAT STMicroelectronics STPS30M60DJF-TR     497-12421-1-ND 511STPS30M60DJFTR 8290456 97W2993 2325863
Q1 1 MOSFET P-CH 30V 14.9A TDSON-8 Infineon BSC084P03NS3GATMA1 Infineon BSC084P03NS3GATMA1 BSC084P03NS3 GCT-ND 726BSC084P03NS3EG      
C1 1 CAP CER 10UF 25V X7S 0805 Murata GRM21BC71E106KE11L     490-10496-1-ND 81GRM21BC71E106KE1L 8851764 96Y9268 2611935
C2 10 CAP CER 0.1UF 16V X7R 0603 Yageo CC0603KRX7R7BB104     311-1088-1-ND 603CC603KRX7R7BB104 6698763 68R4769 432210
Cf 1 CAP CER 1UF 16V X7R 0603 Yageo CC0603KRX7R7BB105     311-1446-1-ND 603CC603KRX7R7BB105   68R4770 1458900
Cf2,Cin,Co 10 CAP CER 10UF 50V X7R 1206 Kemet C1206C104M5RACTU Kemet C1206C104M5RACTU 1276-6767-1-ND 603CC206KKX5R8BB106   14N2184 2581103
Cf2 alternate 1 CAP CER 220UF 6.3V X5R 1206 Murata GRM31CR60J227ME11L     490-13970-1-ND 81GRM31CR60J227ME1L   55Y9932 2494472
Coff 10 CAP CER 470PF 50V X7R 0603 Samsung CL10B471KB8NNNC     1276-1094-1-ND   7665238    
JMP 1 RES SMD 0.0 OHM JUMPER 3/4W 2010 Yageo RC2010JK-070RL     YAG3380CT-ND 603RC2010JK070RL   98K7919 9235523
R1 eswitch 10 RES SMD 360K OHM 1% 1/10W 0603 Yageo RC0603FR-0736KL     311-360KHRCT-ND 603RC0603FR073K6L   68R0080 1799338
R1 clickie 10 RES SMD 36K OHM 1% 1/10W 0603 Yageo RC0603FR-0736KL     311-36.0KHRCT-ND 603RC0603FR073K6L   68R0080 1799338
R2 eswitch 10 RES SMD 47K OHM 1% 1/10W 0603 Yageo RC0603FR-0747KL     311-47.0KHRCT-ND 603RC0603FR074K7L 5047363 68R0098 2146120
R2clk, Roff 10 RES SMD 4.7K OHM 1% 1/10W 0603 Yageo RC0603FR-0747KL     311-4.70KHRCT-ND 603RC0603FR074K7L 5047363 68R0098 2146120
R5 10 RES SMD 4.7 OHM 1% 1/8W 060 Vishay MCT06030C4708FP500 Vishay MCT06030C4708FP500 RNCP0603FTD4R70CT-ND 594MCT06030C4701FP5   96Y9432 2614446
Rf2 10 RES SMD 3.9K OHM 1% 1/10W 0603 Yageo RC0603FR-07390KL     311-3.90KHRCT-ND 603RC0603FR0739KL 5046916 68R0081 2143821
Rf3 10 RES SMD 2.7K OHM 1% 1/10W 0603 Yageo RC0603FR-07270KL     311-2.70KHRCT-ND 603RC0603FR0727KL   68R0067 2136427
Rsns 3 RES SMD 0.075 OHM 1% 2W 2512 International Resistive LRC-LR2512LF-01-R075-F International Resistive LRC-LR2512LF-01-R075-F 696-1670-1-ND 66LR2512LFR075F 7717792 88K2583 1254661

 

It's also possible to feed it alternate MPN's for each row so that the cart will get filled for all vendors.

 

It is complimentary to this:

https://greasyfork.org/en/scripts/19082-digikey-export-cart-possibly-to-bom.  Which exports digikey shopping carts. Must install greasemonkey first.

 

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