Kind of Urgent National Semiconductor Driver Questions

[Sanghera]

Hi all,
I was just wondering if these are a good buy, they are for single phase motors ????? I think if there is such thing, they are 3A to 6A and 55 Volts H Bridge thingy, but they only have 11 pins, what's up with that. LMD18200T, 3A, 55V Hl-Bridge Motor Driver, 11 Pin TO220, National Semiconductor. I don't know if these are kind of a scam because of the 11 pin. I sort of need to make a decision fast.
Thanks.

[Sanghera]

Here's the link.

http://www.national.com/ds/LM/LMD18200.pdf

Thanks.

[Sanghera]

Also, does this thing put out step and dir signals?
Here's the link.

http://www.national.com/ds/LM/LMD18200.pdf

Thanks.

[tpworks]

looks like it takes 2 of the to220 11 pin or 1 of the 24 pin dip also looks like you will have to use aditional components to make step/dir

[Sanghera]

So, these are not step and dir? What kind of components would be needed to make it work with a normal stepper?
Thanks.

[kfong]

Hi Sanghera,

The lmd18200 does not make a good stepper driver chip you need the lmd18245 chip.

Kin Fong

[Sanghera]

What's so bad about the LMD18200? Also, what is the maximum amperage on your boards that you suggest, I read 3 amps then I read 6 amps, is it that you have to use a heat sink after 3 amps?
Thanks.

[kfong]

Hi Sanghera,

The LMD18200 and LMD18245 are along the same family line. The LMD18245 has more features and makes it easier to microstep and design with. They both have the same ratings. The 6amps you read is the max peak current, this is not the average continuous current of 3amps. This chip can take quite a lot of abuse.

Kin Fong