Any EEs in the house?
#1
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Any EEs in the house?
So... I want to be able to "turn down" the speed of my electric R/C truck. I know PWM is usually used to do this, But I think I found a circuit that can be retrofitted. I found a variable speed fan in an old PC I was given, and with a 5K pot I can adjust between 0-1K to get the full range of motor speed.
Now here'* what I'm wondering, The circuit uses a LB1861 which seems to be good for 1.5A, I know the motor I want to control has to be over that, Can I use a transistor or MOSFET to 'up' the amperage and make the circuit work?
The datasheet on the LB1861:
http://www.ortodoxism.ro/datasheets/sanyo/ds_pdf
Now here'* what I'm wondering, The circuit uses a LB1861 which seems to be good for 1.5A, I know the motor I want to control has to be over that, Can I use a transistor or MOSFET to 'up' the amperage and make the circuit work?
The datasheet on the LB1861:
http://www.ortodoxism.ro/datasheets/sanyo/ds_pdf
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LOL, I was wondering when this was going to get a reply...
I got ahold of a guy in my SCCA club who came over and showed me how to do it with an NPN a PNP and two MOSFETs. It wastes some of my mAh, but it works.
I got ahold of a guy in my SCCA club who came over and showed me how to do it with an NPN a PNP and two MOSFETs. It wastes some of my mAh, but it works.
#4
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How did you do this Dame..
Depending the transistors NPN and PNP you would have needed to supply their required voltage/ground to trigger them right?
Depending the transistors NPN and PNP you would have needed to supply their required voltage/ground to trigger them right?
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supply voltage powers the MOSFETs and transistors, the LB1861 triggers the transistors, which trigger the MOSFETs.
Like half of this since I only use one direction.
http://www.bobblick.com/techref/proj...e/hbridge.html
Like half of this since I only use one direction.
http://www.bobblick.com/techref/proj...e/hbridge.html
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Originally Posted by MOS95B
So, um, why didn't you just get a smaller motor for the truck? or is it one of them cheapies you can't change parts in?
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Originally Posted by Damemorder
Originally Posted by MOS95B
So, um, why didn't you just get a smaller motor for the truck? or is it one of them cheapies you can't change parts in?
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I would be using more VCR parts If I hadn't found this thing in the trash, Makes some of it easier.
I'm into scale rock crawling anyway, so even if I had the cash to have a truck, It wouldn't be useful.
I'm into scale rock crawling anyway, so even if I had the cash to have a truck, It wouldn't be useful.
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