This is it !

[Farmhand]

Yes well, maybe i could do it with these 4001 oscillators but I think I would
prefer to use Op-Amps, I have some here, but i'm not sure if i'm up to it for a
while, i've got other work to do thats backing up. Sheds to build and so on.

I ordered another solar panel yesterday just a 35 watt one. I mainly got it to
free up two 10 watt panels for other things. I think I will build a free energy
shed. I'll try to fit it out with all different types of working free energy
devices. Does a "fireplace" qualify as a free energy device ? If I don't pay for
the wood ?

Haha

[thatsthat]

UCC27321P driving circuit example

Hi 7imix and thatsthat,

Are you guys getting a better idea of what I'm up to? All independent circuits have been tested now. Okay, I still have not tested the gate driver IC.

I still need a pulse clock. 'thatsthat' ... you said you were a 'digital guy', can you please suggest a pulse clock for the SN74LS family of IC's I'm using right now? Later, I'll be migrating this design to even lower power IC's, but this family has every type of IC I need
for this project.

[EDIT] I'd also appreciate it if you could go over the gate driver (UCC27321P) specs and suggest the correct way to interface the 4.5VDC output of the SN74LS's and the driver chip. Thanks.

Thanks. Later

Hi gmeast,

Thanks for the warm welcome. I found an amazing gem in another thread on this forum for driving the UCC27321P.

Look at Electric Motor Secrets - Page 38 - Post #1137 and #1138

Jetijs is the name of the member who posted a circuit diagram on how he drives two motor coils using this exact chip. I don't want to grab the circuit from that thread and repost without his consent.

His circuit incorporates two opto-interrupters ITR8102's to pulse two coils individually for his application. If you replace the ITR8102 with your digital output straight to IN pin 2 of the driver chip you have yourself a working circuit.

The chip specs say:

• 4-V to 15-V Supply Voltage
• Input voltage for (IN) = -5 V to 6 V or VDD+0.3 (whichever is larger)
  

I looked at the circuit you posted but there is only one page with a list on it without a block diagram. You are really making good progress. Well done!

I'm trying to imagine the circuit you explained and will post on the clock pulse question you asked about.

You wont believe but I found the above thread in this forum by using Google and looking for UCC UCC27321P circuit examples. Google is my friend.

Cheers.

[gmeast]

google

Hi gmeast,

Thanks for the warm welcome. I found an amazing gem in another thread on this forum for driving the UCC27321P.

Look at Electric Motor Secrets - Page 38 - Post #1137 and #1138

Jetijs is the name of the member who posted a circuit diagram on how he drives two motor coils using this exact chip. I don't want to grab the circuit from that thread and repost without his consent.

His circuit incorporates two opto-interrupters ITR8102's to pulse two coils individually for his application. If you replace the ITR8102 with your digital output straight to IN pin 2 of the driver chip you have yourself a working circuit.

The chip specs say:

• 4-V to 15-V Supply Voltage
• Input voltage for (IN) = -5 V to 6 V or VDD+0.3 (whichever is larger)
  

I looked at the circuit you posted but there is only one page with a list on it without a block diagram. You are really making good progress. Well done!

I'm trying to imagine the circuit you explained and will post on the clock pulse question you asked about.

You wont believe but I found the above thread in this forum by using Google and looking for UCC UCC27321P circuit examples. Google is my friend.

Cheers.

Hi thatsthat,

Thanks for verifying that. The UCC27321P I guess is meant to interface directly with with devices like micros such as the ATmega used on the Hex Controller ... though I don't know if that's what's used on the controller. I guess my concern is with the power supply and the need to provide the adequate gate charge to our IRF540Z's sitting on 12VDC battery rails.

Yes ... I know posting member Jetijs. We worked together on the 'Water Spark Plug" thread for about 1 year.

*****GOOGLE******* It is weird sometimes when I'm searching this kind of stuff on google and run into something I have posted myself from these forums ... hear and from Overunity.com.

Sorry you had to search for it ... I didn't think ... I could have linked you to the pdf 'cause I posted it here recently from my ftp space.

As soon as I have a complete counter-based PWM, I'll post details. I just don't want to end up with 'egg on my face' making all of these claims about what it will do if I have grossly miscalculated something or missed something fundamental. I just don't want people spending their valuable time and some $$$ building something I'm not sure 'works as advertised' ... issues like firing the 12VDC FET with a 4.5V signal ... well it seems I'm OK on that ... but stuff LIKE that.

Thanks for verifying. Later

[Farmhand]

Hi all, it's amazing what can be learned from a data sheet. Both these sections from the datasheet for the UCC27321P, provide some usefull info
we can use in other ways and projects. The Bipolar Transistor/MOSFET combo
is usefull. This looks like a really good componant.

It's a good read too.

Common ground for input stage. This ground should be connected very closely to the
source of the power MOSFET which the driver is driving. Grounds are separated to minimize
ringing affects due to output switching di/dt which can affect the input threshold.

output stage
The TrueDrive output stage is capable of supplying ±9-A peak current pulses and swings to both VDD and GND
and can encourage even the most stubborn MOSFETs to switch. The pull-up/pull-down circuits of the driver are
constructed of bipolar and MOSFET transistors in parallel. The peak output current rating is the combined
current from the bipolar and MOSFET transistors. The output resistance is the RDS(ON) of the MOSFET
transistor when the voltage on the driver output is less than the saturation voltage of the bipolar transistor. Each
output stage also provides a very low impedance to overshoot and undershoot due to the body diode of the
external MOSFET. This means that in many cases, external-schottky-clamp diodes are not required.
This unique BiPolar and MOSFET hybrid output architecture (TrueDrive) allows efficient current sourcing at low
supply voltages. The UCC37321/2 family delivers 9 A of gate drive where it is most needed during the MOSFET
switching transition – at the Miller plateau region – providing improved efficiency gains.

What is this Miller plateau region the datasheet speaks of, this sounds important ?

So I went looking and found only one reference in a forum called edaboard.com. Here's the discussion. What's Miller Plateau?

I always end up with more than i can read.

gate plateau voltage
When you look at the datasheet for a MOSFET, in the gate charge characteristic you will see a flat, horizontal portion. That is the so-called Miller plateau. When the device switches, the gate voltage is actually clamped to the plateau voltage and stays there until sufficient charge has been added/ removed for the device to switch.
It is useful in estimating the driving requirements, because it tells you the voltage of the plateau and the required charge to switch the device. Thus, you can calculate the actual gate drive resistor, for a given switching time.

The charge injected is:
Qgate=Igate*tsw

But
Igate=(Vcc-Vplateau)/Rgate

where Vcc is the supply voltage of your driver (actually it should be its peak output voltage, but often that is what we use for a quick estimate).

Thus, you can select Rgate to obtain the required tsw, for a given device. Qgate is the difference between the charges at the ends of the plateau.


Look at the picture. The Miller plateau is in the middle. The plateau voltage is about 1.8V, and the required gate charge is 2.2-0.7≈1.5nC.

This is a very fast, low power device. Other devices, like power MOSFETs, have gate charges in the tens and hundreds of nanocoulombs.

It's fun to read but I haven't worked out what it all means yet.

Cheers

[7imix]

For a clock, I have been looking into phase-locked loops and direct digital synthesizers. A DDS is about $20 but incorporates the entire variable clock into a single ic. A PLL can be found for under a dollar but will require quite a bit of supporting circuitry to produce a variable clock.

[gmeast]

clock

For a clock, I have been looking into phase-locked loops and direct digital synthesizers. A DDS is about $20 but incorporates the entire variable clock into a single ic. A PLL can be found for under a dollar but will require quite a bit of supporting circuitry to produce a variable clock.

Hi 7imix,

I've had the same results. That's why we just 'make' a 555 or Op-Amp PWM work. But what about a crystal oscillator circuit. That's gotta' work too. I we need is a good symmetrical 0.5MHz to 5MHz square pulse to clock the circuit.

Things like micros have that in them and let you use either 'internal' oscillator circuitry or an external crystal.

There's also integrated silicone oscillators. Maxim makes one ... 3-pin device.

I guess we keep looking. oooooo! I just found this!

http://02d1852.netsolhost.com/radian...ng/LTC6900.pdf

It sits in the right voltage supply range for the SN74LS stuff. It's an SOT package, but anyone here can wire one of those. I had completely forgotten about Linear Technologies. They have some good stuff!

I'll study this. Later

[gmeast]

Design for Mosfets

Hi all, it's amazing what can be learned from a data sheet. Both these sections from the datasheet for the UCC27321P, provide some usefull info
we can use in other ways and projects. The Bipolar Transistor/MOSFET combo
is usefull. This looks like a really good componant.

It's a good read too.

What is this Miller plateau region the datasheet speaks of, this sounds important ?

So I went looking and found only one reference in a forum called edaboard.com. Here's the discussion. What's Miller Plateau?

I always end up with more than i can read.

It's fun to read but I haven't worked out what it all means yet.

Cheers

Hi Farmhand,

It's easy for some of this stuff to fly right over our heads ... I know. Here's a reference I found a couple of week ago and might be a good reference for someone ... it's just so comprehensive. Here:

http://02d1852.netsolhost.com/radian...or mosfets.pdf for mosfets.pdf

More stuff to read!

Later

[Farmhand]

I did stop to receive my UPS shipment of stuff like resistors, diodes and guess what? ... my power MOSFET driver ICs. Yeah right ... they're going to sit in their box until tomorrow ... ya bet ya no way duuuuude!

Enough surfie. So I have them now and can test when I have time. The spec sheet calls for some careful shielding and care to shield from circuit noise, so I'm sure it's no going to just be 'plug 'n play'. I might have to solder up a socket on a protoboard and blob in some solder for a ground/shield plane. Maybe not. I'm going to try and fire it from the logic gate pulse (that's sitting right at a 1/2usec pulse).

Later

Hi Greg, you were talking about shielding from circuit noise. This is what I was talking about when we go to self charging. More noise and LE as well most likely. It might be necessary, This setup has ruined one of my DMM's, the DMM is now non responsive. Grrrr , it was working fine, untill i tried to measure the charge battery voltage. When I did that the circuit made a funny noise, the current draw went up a bit, and my DMM stopped working. Obviously the charging power went through the DMM instead of the battery. Never happened before. Maybe just coincidence, there is always that chance.

There was only 32 volts on the secondary. But its the good stuff I think.. Anyway another meter is busted. It might be advisable for auto-ranging DMM's to be set to one level above the voltage, I have no idea how they are made but thats my hunch. I'd hate for anyone else to lose a meter like that. It's not the battery, checked that. Oh well.

From the UCC27321P datasheet.

operational circuit layout
It can be a significant challenge to avoid the overshoot/undershoot and ringing issues that can arise from circuit
layout. The low impedance of these drivers and their high di/dt can induce ringing between parasitic inductances and capacitances in the circuit. Utmost care must be used in the circuit layout.
In general, position the driver physically as close to its load as possible. Place a 1-μF bypass capacitor as close
to the output side of the driver as possible, connecting it to pins 1 and 8. Connect a single trace between the
two VDD pins (pin 1 and pin 8); connect a single trace between PGND and AGND (pin 5 and pin 4). If a ground
plane is used, it may be connected to AGND; do not extend the plane beneath the output side of the package
(pins 5 − 8). Connect the load to both OUT pins (pins 7 and 6) with a single trace on the adjacent layer to the
component layer; route the return current path for the output on the component side, directly over the output
path.
Extreme conditions may require decoupling the input power and ground connections from the output power and
ground connections. The UCCx7321/2 has a feature that allows the user to take these extreme measures, if
necessary. There is a small amount of internal impedance of about 15 Ω between the AGND and PGND pins;
there is also a small amount of impedance (∼30 Ω) between the two VDD pins. In order to take advantage of
this feature, connect a 1-μF bypass capacitor between VDD and PGND (pins 5 and 8) and connect a 0.1-μF
bypass capacitor between VDD and AGND (pins 1 and 4). Further decoupling can be achieved by connecting
between the two VDD pins with a jumper that passes through a 40-MHz ferrite bead and connect bias power
only to pin 8. Even more decoupling can be achieved by connecting between AGND and PGND with a pair of
anti-parallel diodes (anode connected to cathode and cathode connected to anode).

These componants have good options for decoupling, the ringing is a sign of good low impedance drivers and correct switching, looks like.

We may want to consider some of these feature's to reduce ringing and circuit noise affecting the driver. Especially when self charging.

The oversoot or (shoot-through) and undershoot are explained in the D class audio driver video I linked, it's related to optimising the (dead time).

YouTube - Silicon Labs Class D Audio Driver and Reference Design

Cheers

[7imix]

The ltc6900 looks AWESOME. Digikey has it for two bucks.

[gmeast]

shielding

Hi Greg, you were talking about shielding from circuit noise. This is what I was talking about when we go to self charging. More noise and LE as well most likely. It might be necessary, This setup has ruined one of my DMM's, the DMM is now non responsive. Grrrr , it was working fine, untill i tried to measure the charge battery voltage. When I did that the circuit made a funny noise, the current draw went up a bit, and my DMM stopped working. Obviously the charging power went through the DMM instead of the battery. Never happened before. Maybe just coincidence, there is always that chance.

There was only 32 volts on the secondary. But its the good stuff I think.. Anyway another meter is busted. It might be advisable for auto-ranging DMM's to be set to one level above the voltage, I have no idea how they are made but thats my hunch. I'd hate for anyone else to lose a meter like that. It's not the battery, checked that. Oh well.

From the UCC27321P datasheet.


These componants have good options for decoupling, the ringing is a sign of good low impedance drivers and correct switching, looks like.

We may want to consider some of these feature's to reduce ringing and circuit noise affecting the driver. Especially when self charging.

The oversoot or (shoot-through) and undershoot are explained in the D class audio driver video I linked, it's related to optimising the (dead time).

YouTube - Silicon Labs Class D Audio Driver and Reference Design

Cheers

Hi Farmhand,

These are issues to be taken seriously. As an assist, I recommend we study the 3GBoard and see what Bob did on that PCB.

Here it is:
http://02d1852.netsolhost.com/radian...ging/pwm3g.jpg

You can see some good detail from this picture, and in fact I think you could build a schematic from it.

It's nice to have a component that's ready-made for addressing the noise issue like this component is.

Later

[gmeast]

Ltc6900

The ltc6900 looks AWESOME. Digikey has it for two bucks.

Hi 7imix,

"It's what the doctor ordered" ... so to speak. Using a 0.1PPM TC R2R Ladder and a dip switch (or a binary weighted resistor array and dip switch), this can be programmable (on the fly), like the design requires. Also, did you notice it has a 3-state 'divide by' set for 1:1, 10:1 and 100:1? What great features! .... I only wish it was available in a DIP package. Few, if any, of LT's components are available in DIP packaging ... bummer! But I have used many SO chips for various things and its just a matter of patience and dexterity when soldering them up (and a good illuminated magnifier to look through).

Thanks.

Later

[Farmhand]

OK I think maybe the meter was an easier path than the battery, Still angry about that, I think from now on I will use an analogue meter for measuring the charging battery voltage. Maybe they are immune to that kind of damage.

Gmeast said,

These are issues to be taken seriously. As an assist, I recommend we study the 3GBoard and see what Bob did on that PCB.

Here it is:
http://02d1852.netsolhost.com/radian...ging/pwm3g.jpg

You can see some good detail from this picture, and in fact I think you could build a schematic from it.

It's nice to have a component that's ready-made for addressing the noise issue like this component is.

Later

I'll check it out and see what I can come up with for a circuit drawing. I've never done a PCB layout before, only schematics, I have "Express PCB/SHC"
free stuff, not sure how to go from schematic to PCB layout yet.
Hopefully by the time we get a viable circuit schematic the PCB layout software will no langer be confusing for me.

Damn that DMM. I'll have to replace it.

Cheers

[gmeast]

Pcb

OK I think maybe the meter was an easier path than the battery, Still angry about that, I think from now on I will use an analogue meter for measuring the charging battery voltage. Maybe they are immune to that kind of damage.



I'll check it out and see what I can come up with for a circuit drawing. I've never done a PCB layout before, only schematics, I have "Express PCB/SHC"
free stuff, not sure how to go from schematic to PCB layout yet.
Hopefully by the time we get a viable circuit schematic the PCB layout software will no langer be confusing for me.

Damn that DMM. I'll have to replace it.

Cheers

Hi Farmhand,

I have used Pentalogix. They provide FreePCB which is easy to use. Pentalogix is a quick-turn board house and they quote prototype runs of 5 pcs on up. There's a one-time engineering free per board design. They're competitive on large runs with most board shops. Plated thru holes are not extra, but plain holes are because they have to drill out the plating????

Unfortunately with FreePCB I cant export anything useful .... only to Pentalogix. Maybe I''ll take a look at your software and give it a go.

Anyway, we'll need to go to a board eventually because there are always more traces on a digital board.

I ordered a couple of the LTC6900 oscillators tonight. I also ordered a couple of very generic digital comparators for test in the same order. They're coming US Postal Service so who knows when I'll get them?

@7imix: I'll post some scope captures of the LTC6900 when I get one running. That will be about 5 minutes after I open the delivery package. I'm very excited about finding that thing!

That's my update for now.

Later

[gmeast]

express pcb

Hi Farmhand,

I just installed Express PCB. It is the same 'quick-turn' software/service as Pentalogix. However, their '$51-for-3-prototype-boards' is a much better deal than Pentalogix's costs. At last glance, they wanted $150 one-time engineering charge ... that's a little high, but they do double check your files and help you fix anything for free before they burn the board ... so maybe a toss-up? ExpressPCB may offer the same though ... dunno'.

Later

[Farmhand]

Hi Farmhand,

I just installed Express PCB. It is the same 'quick-turn' software/service as Pentalogix. However, their '$51-for-3-prototype-boards' is a much better deal than Pentalogix's costs. At last glance, they wanted $150 one-time engineering charge ... that's a little high, but they do double check your files and help you fix anything for free before they burn the board ... so maybe a toss-up? ExpressPCB may offer the same though ... dunno'.

Later

Hey Greg, I think i'm getting ahead of myself maybe, there are definately
going to be too many holes in the boards to make ourselves though. I'm up for software suggestions if anyone has any, i'm willing to pay for good software.
I'll check out the one you use first Greg.

One of those little computer controlled milling machines would be very usefull
for making all kinds of stuff for electronics. Making the holes in a pcb blank
would be a snap with one of those. Ahh to dream.

Cheers

Yippee, looks like I might have all of a sudden broken the Mhz barrier, check the shots. Thats just one coil the rest are open. Playing around with very narrow pulse and bamo 600Ma draw, can sneak it down to 300Ma stays around 1.5 Mhz, Fet still cool and very good charging as I would expect with .5 amp or so. I can't see it properly on the scope, I think because either I don't know how to use it for that frequency or it can't read it.

Scope say's it's a 5 Mhz scope , maybe thats just the sample rate or something. So it looks like with tweeking low Mhz range is possible with these 4001 chips. It fluctuates a bit though and is far from being accuritly settable.
It is interesting though.

Here are some shots

http://9xfdag.bay.livefilestore.com/...002.JPG?psid=1

Ghost Trace
http://9xfdag.bay.livefilestore.com/...005.JPG?psid=1

Starfish Trace
http://9xfdag.bay.livefilestore.com/...003.JPG?psid=1

Maybe the starfish trace above looks a little bit like the one at 1.16 mins in the video below. If I added a choke it might look even more like it.
YouTube - OU Charging effect of the hex controller

Here's my analogue scope control panel. Anyone know how I should set it for Mhz. Settings say - 1k- 10k , 10k-100k , LINE , Looks like it only reads to 100k to me.
http://9xfdag.bay.livefilestore.com/...008.JPG?psid=1

Cheers