------- Forwarded Message Follows -------
Date:          Thu, 11 Sep 1997 06:18:18 -0400 (EDT)
From:          XYGAX@aol.com
To:            lilel@toastmaster.com
Subject:       Re: Cheap Motor drivers [OT]

Lawrence

>I have just discovered a Natnioal device LM18200 I think the number
>is correct. It is a full H bridge 3A to 50V needs logic to drive it
>and it works in parellel with others. I made a 60W sine wave
>inverter from two of these a transformer a PFC chip and 24v DC. it
>is described as a motor driver in a 10 pin packet with tab. It
>contains all the current limit bits bootstrap for the high side and
>overtemp protection. I am planing to generate the PWM pattern with a
>'71 and increase the bus voltage to 48v a three chip soulition to DC
>to AC conversion at just over 100W coludnt be more simple (famous
>last words) worth a little pondering !!!

Looks interesting. When you get the code written for sine wave PWM
I'd like to see it.  I've got an old project laying around to make an
inverter.


>If you want real power IXYS makes a 200A 1200V half bridge IGBT
>module with inbuilt drivers needs 15v and 5v logic to drive them or
>Semikron makes a SKHI200 which is a half bridge driver but no IGBT
>or FET but will drive both again needs 15v and logic drive will
>drive multiple parellel IGBT's  max 5 (1250A @ 1200V) of course at
>these levels the miller cap is huge and the module is v expensive.
>For more modest power levels we use a SI9910DJ from Siliconex drives
>fets directly and IGBT's when you add a PNP transistor to discharge
>the gate.

>Cheers Steve.....

1250A at 1200 volts....wow!  What is it for, Wheeling power between
nuclear power plants?! I guess I don't need anything quite that big.
A 3 watt motor would be fine.
Best Regards,

Lawrence Lile