Micro-Drive laser driver by rkcstr

Re: Micro-Drive laser driver – fits Aixiz module

SenKat_Stonetek said:

I'll gladly pay the increased price, and welcome you back to sanity....I TOLD you that you were nuts for selling them so cheap - that is why I insisted on paying you a little more than you wanted  Damn, I love it when I am right ! (it happens so seldom...ya know !) hehehehehe

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Haha, I know...  but, as I said, I wanted to be as fair as possible on the prices.

Also, I don't know if this would influence anyone to consider a price raise, but I've been working on an adjustable version that would possibly be able to go from somewhere around 30mA to over 400mA.  The cost of parts increases, so I would have to increase price, though.  I'm still trying to figure out if the design will work.  I've posted a schematic in the Experiments & Modifications forum in my topic I started there, but haven't received any comments on it.


Update, from Post #2:
All orders currently are shipped. I have a final exam next Thursday, so I probably won't be working on any orders Mon-Wed. I'll try to get any new orders from this point on finished by the end of the weekend to be out on Monday, but after that they probably won't go out until next Friday. Thanks for your patience

Re: Micro-Drive laser driver – fits Aixiz module

A couple announcements:

First

I'm trying to finalize the design and prepare for order parts for an adjustable version of my driver.  Planning to be capable of driving a range from about 20-30mA up to somewhere in the vicininty of 420mA.  

I plan to offer it in one range form (makes it easier because I won't have to "make to order" like previously), but the range can be modified to cap the peak output or raise the minimum output to improve adjustability in the higher range, by only changing 1 resistor in either case.  

It would be the same size as the driver I make now.

The price would be more though, due to increased parts cost (about twice as expensive).  With the assembled driver likely being $7.50 and the kit (or unassembled) being $4.50.  I may offer a "custom" range for extra.

Second

I found a sort of quirk with my driver...

Recently I've began to question something I see when I test the drivers, specifically the low powered drivers (<50mA), where the output I measure is consistently lower than I expect to see.  I figured it was just my test setup (some series diodes and a 1ohm resistor) figuring either the resistor was slightly off (0.2 ohms would do it) or my meter was slightly off, or both.

But, after I experimented a little bit, I found that adding one of the ceramic caps I use (small 1uf ones) across the resistor, the output goes up to what I expected.

Now, this isn't anything to be concerned about, the output seems to only sag about 15% at 38mA and less than 10% at 50mA, meaning the output of a 38mA driver may be more like 32mA or 50mA around 45mA or so.  And, this will not affect the diode in any way aside from slightly underpowering it.

The thing I want to mention is that this was not referred to in any way in the manufacturer's datasheet and it only occurs with drivers under somwhere around 50mA.  The 76, 87, 100 and up are all normal, there's just something with the low output drivers that the chip doesn't do well without the capacitor.  And, I've tried the capacitor on the higher values and it actually DECREASES output!  So, that's why I'm calling it a quirk, because it doesn't seem to make any sense (at least to me, but I'm no engineer).

So, I'm not sure this really matters to anyone, because you all have seemed happy with the drivers so far, but I want to be straight with everyone, so if you feel it is a problem, let me know and we'll work something out.

I'll be sending an email out to the persons who bought the drivers that it may affect, just in case they don't read my thread religiously  ;D

Re: Micro-Drive laser driver – fits Aixiz module

Received both my drivers on Friday, and they work great. Thanks rkcstr!!

Do you still plan on making the fixed value drivers once you start making the adjustable ones?

Re: Micro-Drive laser driver – fits Aixiz module

No need to email me, RKCSTR - these drivers are incredible - LOVE 'EM !

Re: Micro-Drive laser driver – fits Aixiz module

somail said:

Received both my drivers on Friday, and they work great.  Thanks rkcstr!!

Do you still plan on making the fixed value drivers once you start making the adjustable ones?

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I have a TON of the resistors for the fixed value drivers (I ordered about 1000 of each, lol). So, yes, I'll continue to offer the fixed value drivers until I run out of the necessary parts.

Re: Micro-Drive laser driver – fits Aixiz module

SenKat_Stonetek said:

No need to email me, RKCSTR - these drivers are incredible - LOVE 'EM !

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I sent you an email, haha... I misread and thought you "needed" me to email you, lol. Oh well.

Re: Micro-Drive laser driver – fits Aixiz module

rkcstr said:

[quote author=SenKat_Stonetek link=1206947255/225#227 date=1211117980]No need to email me, RKCSTR - these drivers are incredible - LOVE 'EM !

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I sent you an email, haha... I misread and thought you "needed" me to email you, lol. Oh well.[/quote]

lol thats funny ;D

Re: Micro-Drive laser driver – fits Aixiz module

hi i am going to order a few drivers soon and i was wondering if you could include a a small capacitor?

Thanks,
Mitch

Re: Micro-Drive laser driver – fits Aixiz module

rubberband said:

hi i am going to order a few drivers soon and i was wondering if you could include a a small capacitor?

Thanks,
Mitch

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All new drivers I'm already putting the cap on there when necessary.

-Ryan

Re: Micro-Drive laser driver – fits Aixiz module

oh ok cool thanks expect my order soon

Thanks,
Mitch

Re: Micro-Drive laser driver – fits Aixiz module

SenKat_Stonetek said:

I'll gladly pay the increased price, and welcome you back to sanity....I TOLD you that you were nuts for selling them so cheap - that is why I insisted on paying you a little more than you wanted  Damn, I love it when I am right ! (it happens so seldom...ya know !) hehehehehe

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I agree, that price is too cheap for an assembled driver, not that I minded!

Re: Micro-Drive laser driver – fits Aixiz module

icecruncher said:

I agree, that price is too cheap for an assembled driver, not that I minded!

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Haha, well, I originally priced them to be similar to a "group buy" type of price but available immediately rather than having to wait.

The price is kind of low to make a fair earning on them considering the low volume I sell, so I may increase prices a small amount, but we'll see.

Re: Micro-Drive laser driver – fits Aixiz module

Official [sort of] Announcement:

I'm going to be offering a new adjustable form of my driver.

• It will be capable of driving from about 27mA to ~430mA with one driver.
• It will be the same size, will be a direct replacement for the non-adjustable driver, but you have full-choice of your output current.
• The output range can be modified from full-range to either a low power/405nm range (27mA to ~150mA), or a high-power/red burner range (~150 mA to ~430mA).
• The limited ranges allow for more easily adjusting output within a range, while full-range is most versatile for a variety of applications, but adjustments will need to be made more carefully.
• A test load board will also be an optional (but recommended) accessory, which includes diodes necessary to test a red or 405nm voltage output, a 1W 1ohm resistor for ease of measuring current simply with a multimeter capable of measuring a mV range. It will also feature automatic output capacitor discharge via a shunt resistor to less than 0.0001% of original capacity in 1.3s. It will be available separately or with the drivers and you only need one for all of your testing needs!

Pricing will be as follows:
Assembled driver (full-range, low-range or high-range): $7.75
Unassembled driver (includes necessary parts for all range settings): $4.75
Test Load (purchased separately): $4
Test Load (with a driver purchase): $3
Test Load unassembled (no driver purchase discount): $2.50

Due to the design, I will be able to make these ahead of time to hopefully have them almost ready-to-ship, with only the range settings (placing 2 resistors) to be completed before they are ready. So, although I'm sure some would say I'm already speedy enough, I could possibly have these out same or next day in most cases.

I expect parts by the end of the week and plan to start selling for next week, pending some final development and testing.

For the previous fixed-value drivers:

Most of the parts remain the same for the adjustable driver as the previous just adding in a few more pricey parts. So, I still have plenty of parts to make the fixed-value drivers, and so will continue to offer them. But, due to realization that my previous price point wasn't really "paying the bills" the price will be rising.

New pricing on fixed-value drivers:
Assembled driver (any setting): $6
Unassembled driver (any setting): $3.50

Test load discount still applies for the fixed-value drivers.

Re: Micro-Drive laser driver – fits Aixiz module

got my driver today very quick shipping, it looks great and even tinier than i thought they were. Now i just have to wait for my diode to get here... *cough* Senkat?? *cough*

Re: Micro-Drive laser driver – fits Aixiz module

motorider826 said:

got my driver today very quick shipping, it looks great and even tinier than i thought they were. Now i just have to wait for my diode to get here... *cough* Senkat?? *cough*

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When did you order?

Re: Micro-Drive laser driver – fits Aixiz module

cbrian4 said:

When did you order?

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If you're wondering about your order, don't worry, it should go out tomorrow

I typically put updates about if there will be delays on my orders in Post #2 of this thread (my Updates & Information). In there I posted that I wouldn't be working on drivers from Mon-Thu because of final exams. So, the driver will be shipped out tomorrow (along with a couple other people who have ordered). Expect it to get to you in about 3-5 days.