FAST high-side drivers/circuitry? - diyAudio
Go Back   Home > Forums > Amplifiers > Power Supplies

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 13th December 2005, 10:21 AM   #1
mzzj is offline mzzj  Finland
diyAudio Member
 
Join Date: Jul 2005
Location: 65N 25E
Question FAST high-side drivers/circuitry?

does anyone know fast, high-current(6A or more) high-side drivers for 300-400v dc bus voltage?
IR2110 and relatives are piece of sh*t...

Currently i am using toroidal gate drive transformers in my 4kW subwoofer-inverter but GTDs leakage inductance is limiting performance somewhat. With DIY toroid I can get sub-250nH leakage inductance witch is great compared to commercial e-core **** from coilcraft etc but i want faster....

4.5kW beast...
  Reply With Quote
Old 13th December 2005, 10:32 AM   #2
Pierre is offline Pierre  France
Banned
 
Join Date: Nov 2004
Location: Paris
I got good results with a TC1427 driver chip driving a T0584 Pulse GDT at around 60-100KHz.
I also had bad experiences with IR2110 for my offline power supply, but good results in a Class-D amplifier (+/-65V rails).
  Reply With Quote
Old 13th December 2005, 11:09 AM   #3
diyAudio Member
 
Join Date: May 2002
Location: Switzerland
If you don't mind some addidional circuitry then you might also consider one of those IXYS low-side drivers combined with a magnetic coupler (which can be used like an optocoupler but is chepaer and faster).

Regards

Charles
  Reply With Quote
Old 13th December 2005, 11:30 AM   #4
Eva is offline Eva  Spain
diyAudio Member
 
Eva's Avatar
 
Join Date: Oct 2003
Location: Near the sea
Send a message via MSN to Eva
Insert a buffer circuit between the pulse transformer and the gates and use the own pulse transformer both for powering the gate driver and for transmitting the drive signal (two independent rectifications are required). You may probably need to modify your circuit in order to drive the transformers in both directions (bipolar pulses).

I've done that kind of high current gate drivers in a cheap way with CD4050 buffers (for a sharp clear drive transient) and ZTX851/ZTX951 fast high-current bipolar transistors. However, you seem to have far more resources and money for experimentation than me, so you may be able to buy dedicated driver ICs and order thight SMD PCBs. You may even use the same TI gate drivers, but place them after the transformer, that's the trick
  Reply With Quote
Old 13th December 2005, 12:15 PM   #5
mzzj is offline mzzj  Finland
diyAudio Member
 
Join Date: Jul 2005
Location: 65N 25E
Quote:
Originally posted by Eva
Insert a buffer circuit between the pulse transformer and the gates and use the own pulse transformer both for powering the gate driver and for transmitting the drive signal (two independent rectifications are required). You may probably need to modify your circuit in order to drive the transformers in both directions (bipolar pulses).

I've done that kind of high current gate drivers in a cheap way with CD4050 buffers (for a sharp clear drive transient) and ZTX851/ZTX951 fast high-current bipolar transistors. However, you seem to have far more resources and money for experimentation than me, so you may be able to buy dedicated driver ICs and order thight SMD PCBs. You may even use the same TI gate drivers, but place them after the transformer, that's the trick
Yeap, something like this i had already in my mind. I am just lazy winding GDT's so all-in smoking driver chip would be nice.

I found quite nice looking pdf with separate power and pulse transformers using small ferrite beads. And it didnt have any limitations on pulse width as usual implementations have.
.http://www.itee.uq.edu.au/~walkerg/p.../fetdrvr-t.pdf

More resources and MONEY?
as a student my financial resources are extremely limited at the moment...
this is near-zero budget project, only paid for 4 pcs. LM361 comparators. Everything else is from scrapped welding machines and other second-hand sources exept sample drivers from TI
  Reply With Quote
Old 13th December 2005, 12:54 PM   #6
Eva is offline Eva  Spain
diyAudio Member
 
Eva's Avatar
 
Join Date: Oct 2003
Location: Near the sea
Send a message via MSN to Eva
You don't need independent power and pulse transformers, a single one may do both things.

Click the image to open in full size.

This is a picture from some old gate drive boards. The one on top is from a buck stage and operates at any duty cycle, the transformer has a center tapped secondary (not strictly required) and the primary was driven from a SG3525 IC. It was able to provide aprox. 80ns crossover time driving a IRFP460 (1 ohm gate resistor). The other is from a full bridge stage, it works much in the same way but only one winding is required to drive it since effective duty cycle is never above 50%.

PD. The CD4050 buffers are absolutely fakes, this is the kind of cr4p that you can buy in local stores in Spain (some units were defective and failed, taking their IRFP460 and ZTX851/ZTX951 away, fortunately others worked fine).
  Reply With Quote
Old 14th December 2005, 04:54 PM   #7
subwo1 is offline subwo1  United States
diyAudio Member
 
subwo1's Avatar
 
Join Date: Jan 2002
Location: North American Continent
If approximately 20ns rise and fall times are good enough, you may like to consider buffering the outputs of your IR2110 with IRF7343 N/P channel MOSFETs. That way, you get 20-30 ampere peak drive and the MOSFETs protect the driver IC from spikes. Those MOSFETs have threshold voltage ratings of about 1 volt, so you can connect them as source followers for ease and simplicity.

EDIT: It is a good idea to place something like a ten or twenty ohm resistor from gates to sources of the source followers to settle down the turnoff voltage quickly. I have also separated the gates and driven the N-channel one through a resistor to slow down the the rise time some.
__________________
USMPS
http://groups.yahoo.com/group/switchmode/
  Reply With Quote
Old 15th December 2005, 03:00 PM   #8
mzzj is offline mzzj  Finland
diyAudio Member
 
Join Date: Jul 2005
Location: 65N 25E
Couldnt get any better rise times driving mosfets directly with ucc37321 than what i get with pulse transformers. Less ringing on gate voltage at least.
  Reply With Quote
Old 23rd December 2005, 02:37 PM   #9
diyAudio Member
 
Join Date: Dec 2005
Location: Dankleight
mzzj:
Your GDT x-formers look neatly made, and you've got a pretty impressive L(leak), but there is a possibility you could do better than that.

These are 2 GDT I made for a 1KW SMPS, (I was lazy, I made one trafo for all switches) .
The first, has 12 strands twisted together, 4 filar primary with 2-filar each secondary. It has a leakage L of about 0.14uH.

Click the image to open in full size.

As I understand it, for lowest leakage L, the idea is the make the primary and secondary "occupy same space", or as close to that as possible. (ok, this is heresy if you're looking for regulatory approval--creepage/clearance are gone) .

The second GDT was made from 12 turns of USB cable wound on a 26mm toroid, and had a L(leak) of under 0.10 uH. It has 4 vinyl insulated conductors ( the secondaries) inside a braided shield (the primary), and probably has better insulation characteristics.


Click the image to open in full size.

I had intended to test the "winding inside a tube" model and didn't bother to make it neat. It works well enough that you could find a bare shield braid, put insulated conductors through it, and make a much neater job than I did.
Ultimately the creepage/clearance deal depends on your particular primary-secondary voltage difference, and your level of comfort with with your handywork.

Joseph

Click the image to open in full size.
  Reply With Quote
Old 23rd December 2005, 03:48 PM   #10
poobah is offline poobah  United States
diyAudio Member
 
poobah's Avatar
 
Join Date: Nov 2005
mzzj,

Here is a link to a chip-set that use one trans for both power and signal... just some food for thought. I used these once, and I did not like them, very complicated, but the principle is worth learning. They are now obsolete, as they should be.

http://focus.ti.com/lit/ds/symlink/uc3727.pdf

My best experience has always been with one trans for floating power and an opto for the signal. I agree, the IR21XX are s**t.
I don't know your requirements for propagation delay and timing accuracy. Maybe too much jitter for you. I don't know of a chip that has the 4-5 Amp drive you want... I think you'll need discrete buffers for the high amperage drive.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Delay matching in IR2xxx low and high side gate drivers Eva Power Supplies 8 10th June 2007 08:02 PM
High side driver ckt using ocs rejithcv Power Supplies 8 16th November 2006 02:52 AM
how to model fast high frequency op-amps zilog Class D 0 28th November 2005 03:53 PM
Low side driver as a High side fr0st Parts 0 8th May 2004 02:14 PM
Fast High-End Design from Elektor May 1997 JDeV Solid State 1 12th November 2003 03:43 AM


New To Site? Need Help?

All times are GMT. The time now is 02:47 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2