No New Projects?

[planters]

That 7.5 A current limit was for Steve's itty bitty fiber pumped green (just yanking your chain Steve). The green I built is pumped by more powerful free space diodes. Parallel is fine though if there are no issues with load balancing etc. and the flexibility of adding drivers to handle additional current is useful.

Another thought. Do you think the reputation of the DPSS lasers for bad modulation performance may in part be due to the drivers? The Laserwave OEM DPSS I purchased has a driver board that is not physically very impressive and these CN lasers in the 1-3W range need 5-10A of drive current. If your driver works well then maybe DPSS lasers driven by them will better match the straight diode lasers.

[planters]

White-Light,

The reason why no exact speed has been given by Pangolin is because no driver exists on the planet currently that can drive the new scanners to their limits.

Also, how anyone doubt their ability to finally deliver the product is beyond me given the proven company record and existing manufacturing contacts / clout.

Don't get me wrong. But, when I asked Bill @ SELEM face to face if the scanner motors he brought to the meeting would be provided with amplifies he said "of course". And, when I asked him for a time frame, he said they(the system was implied here) would have to be ready for P. West. Now, in his defense, I believe that these scanner systems will be completed and delivered and the price will be competitive ( with whom, I'm not yet sure). When I said uncertain, I was speaking about when and not if.

This was an example that time is a factor and if these drivers are available soon then why not compare them to the existing models before entering a group buy, but if the delay is significant then... well.

Ditto to Norty except not 10 a penny. Ill trade you for a low power CN clone!

[chad]

Chad,
You may be right, but why do you assume no negative rail? I can't see the test set up at all.

The point I was trying to make is with +12 and gnd there is no -12v rail. There should not be a negative spike, there is nothing in the driver that is capable of doing this minus some small inductance of the current shunt and pcb traces. He has a full scope graduation worth of a negative spike. Most likely this is an inductance from the scope probe + what ever wiring he is using to go to the diodes. Modulating 12v at 1. something amps at 30khz is not a trivial thing. You have to pay attention to inductance of wire at those levels and design accordingly.
DrLava's video is convincing, to me at least. I have measured these drivers at close to maximum ratings while modulating and I have never seen such a spike.

I am not discouraging the new driver design. Like swamidog said , more is better. Until I have one that I can hookup and give a full workout I can't say what the ultimate performance is like. I am sure it will be great. But so is the flexmod If used correctly.

Can't wait to see one.

chad

[planters]

The point I was trying to make is with +12 and gnd there is no -12v rail. There should not be a negative spike, there is nothing in the driver that is capable of doing this minus some small inductance of the current shunt and pcb traces.

I see. Yes, that makes sense. Maybe an image of the test set up would help. In any case, we need a driver before we can compare and so I'll be patient.

[kecked]

Guys the board you saw was for testing only. We have not chosen the gain structure, the sense, the drive transistor, the opamp, the feedback filter....ie there is a ways to go here. 4-6amps yes. Higher I am not certain. Par drivers not clear that can be done. This driver is coming together and in time will be a design but is at least a few months from selection and layout of a real board. Hell that was auto traced in pcbartist! If you need drivers now go get bad pips or join the group buy. As for 48A. Not happening ever. You'd need a pass bank of at 8-16 transistors depending on what you choose.

Let me also be clear. I HATE politics. Ill be gone like the wind if you all start jumping each other. I'm trying to help but if you just want to snipe each other leave me out. This is a hobby for me. I will never make a penny ever and don't want to do so. I do however want a driver that is always available and does what we want it to do within reason like max 6A or so.

[mixedgas]

Gentlemen, and the odd Lady or Two.

Before we go slagging each and every "brand" of driver, lets establish some standardized test conditions shall we?

We need to decide on affordable STANDARDIZED REPRODUCABLE test conditions: (partial list)

Control signal source impedance (Ilda targets 600 ohms or less in some documents)
Control step on/off ratio
Control signal rise/fall times
Test Bench Power supply impedance
Amount of external flter capacitance added to power supply for "stiffness"
Definition of "I-V curve compliance"
Dummy Load
Fast photodiode for linearity checks.
Length of lead wires
A ramp waveform for linearity
How to handle offset
Probing system. Yes, the type of probe matters, and differential probes are prefered. (there are ways to avoid Diff probes, but not many)
Non inductive sense resistor.
Definition of 3dB bandwith as pertains to laser shows.
Means for verifying oscilloscope performance.

I could go on....

Define the standard test setup first please......

Steve

[drlava]

Adam and team, it's just bad form as Steve said to start off your sales pitch by saying all drivers out there aren't good drivers. When you introduce a new driver, you should promote its positive qualities. Your scope plot is of voltage, not current, and diodes and lead lines are nonlinear at high frequencies. No mention was made of lead length. You should re-test using the recommended setup for series diode arrays: placing a 0.1uf cap on the pins of the diodes, and using a short lead length as it would have in a standard laser module. These are the standard suggestions I make to users creating series setups.


planters, the P3 (actually P3.2) group buy was started because a lot of members expressed desire for another round, and I have a few tweaks that can be made to make it even better. I started it before seeing this thread, but think it still has its place as the P3.2 is an excellent driver that is ready to be built now.

[White-Light]

White-Light,


Don't get me wrong. But, when I asked Bill @ SELEM face to face if the scanner motors he brought to the meeting would be provided with amplifies he said "of course".

I understand from my conversations there will be 2 versions:

1. Scanners only for OEM integration into an existing scanner block / driver set (I believe they fit Cambridge, unsure of others)

2. Full Scanner set with scanners, block and drivers

As for time frame, who knows, thats going to be down to commercial pressures.

It appears the launch was more about demonstrating the technology than a full release atm as OEM's are the ones who are getting the 1st batches. I believe the full kits will come later.

[-bart-]

You guys sure know how to ruin what could have been a perfect product launch.
If you resort to these practices you're bound to be countered with equal strategies.

But no, when that happens, such people are Pango-haters, and that's good, 'cause you always need some haters, just to know you're on the right track.

When you introduce a new driver, you should promote its positive qualities.

QFT

At times, vendors are criticized for intentionally producing vaporware in order to keep customers from switching to competitive products that offer more features.

Just imagine, this Aerospace Driver hasn't officially been launched, some intended preliminary specs are coughed.
Yet, some of the sellers/defs has the nerve to post some dubious scope plots of a competing product.
How do Americans call that ? Swiftboating ?

At least have the honesty to have your product tested against competitors "brand X" and "brand Y" by an independent person *when it is released*.

As I routinely post here, I do not routinely monitor PL.

[-bart-]

flexmod.jpg

Ringing on a flexmod ?

No such thing !