Peter J. must be mad at me as he has been throwing curve balls.
This is about your original statement that BJTs somehow drop many volts, and my reply is not about the suitability of any BJT for this switching app (not audio) but that you must be thinking about darlingtons. Noticed I never recommended any BJTs, only MOSFETs, despite your twisting of facts and replies.
@eagletalontim: My first reply was that you could get away with a simple relay + one MOSFET for your app as the relay wouldn't suffer contact arcing since you would rely on the MOSFET to switch the power while the relay only ever changed direction infrequently and always while the power to the motor was turned off to the relay. You can use 3.3V logic level power MOSFET, a DPDT relay and that is all. Normally I wouldn't recommend a relay at all but for your application it is suitable and simple.
The VNH5019A-E you mentioned in an earlier post should work just fine for this. If anything it might be a bit of overkill, so I would measure the current draws of the actuators in operation first. it may be that what you have now will be fine.
I have already purchased the SparkFun components as they are pretty much a "plug and play" setup for me. I can use my existing boards and don't have to worry about trying to figure out how to run the 30A IC. 15A is more than enough since the specs of the actuator are 10A @ 1000lb. The solar panel frame is for the most part balanced so I would imagine I would never hit 1000lb even in high wind, but better to be safe than sorry
I have already purchased the SparkFun components as they are pretty much a "plug and play" setup for me. I can use my existing boards and don't have to worry about trying to figure out how to run the 30A IC. 15A is more than enough since the specs of the actuator are 10A @ 1000lb. The solar panel frame is for the most part balanced so I would imagine I would never hit 1000lb even in high wind, but better to be safe than sorry
Looks like a very good choice, although a bit pricey. Probably couldn't build the equivalent for less than that in any case.
I looked at the Sparkfun schematic and other documents for the level shifter and it seems to have provided the pull-up resistors that are required within the circuitry of the chip on that board.
So the answer is NO.
All you need to do is to provide +5VDC and +3.3VDC to the right places.
In this case, you don't require pull-up resistors -- but there are other ways to do this with MOSfets or transistors that do require the pull-up resistors.
Comments
http://www.ebay.com.au/itm/111401192055
I know nothing about it, and I'm a software person, but there it is...
Peter J. must be mad at me as he has been throwing curve balls.
This is about your original statement that BJTs somehow drop many volts, and my reply is not about the suitability of any BJT for this switching app (not audio) but that you must be thinking about darlingtons. Noticed I never recommended any BJTs, only MOSFETs, despite your twisting of facts and replies.
@eagletalontim: My first reply was that you could get away with a simple relay + one MOSFET for your app as the relay wouldn't suffer contact arcing since you would rely on the MOSFET to switch the power while the relay only ever changed direction infrequently and always while the power to the motor was turned off to the relay. You can use 3.3V logic level power MOSFET, a DPDT relay and that is all. Normally I wouldn't recommend a relay at all but for your application it is suitable and simple.
Looks like a very good choice, although a bit pricey. Probably couldn't build the equivalent for less than that in any case.
Level shifter : https://www.sparkfun.com/products/11771
bridge : https://www.sparkfun.com/products/9107
So the answer is NO.
All you need to do is to provide +5VDC and +3.3VDC to the right places.
In this case, you don't require pull-up resistors -- but there are other ways to do this with MOSfets or transistors that do require the pull-up resistors.