May i know can this circuit work to give 4 directions (forward, backward, left and right?) with the use of onli 1 motor (as shown in the schematic)??
or i must 2 motors in order for it to work in 4 directions?
and also for the Vcc. when i supply a 12V to the Vcc, the voltage level at the DC power supply will drop from 12V to around 4V only. May i know why could this happen?
this motor circuit movement shall be control by an interface at the PC side through a programmable Atmel 89C52 uC.
yes i knowthat Vcc is up there but where isit 4V as you said? you mentioned something about voltage drop. and as nigel said how do you plan to work one motor 4 ways as it yes only runs clockwire and couterclockwise.
so Mr Nigel is there any suggestion u would recommend to modify the circuit above in order for the motor to move in 4 direction (forward, backward, left and right)???
if i would to add in another motor to give another 2 directions, is it this way?
[quote = "bloody-orc"]yes i knowthat Vcc is up there but where isit 4V as you said? you mentioned something about voltage drop. and as nigel said how do you plan to work one motor 4 ways as it yes only runs clockwire and couterclockwise.[/quote]
the 4V voltage drop is on the DC power supply. First i set the Dc power supply to 12V....when i connect the 12V to the circuit, the Dc power supply auto drop to onli around 4V.Anyone know why this happen?
so Mr Nigel is there any suggestion u would recommend to modify the circuit above in order for the motor to move in 4 direction (forward, backward, left and right)???
if i would to add in another motor to give another 2 directions, is it this way?
You simply cannot move a motor in more than 2 directions (clockwise and counter clockwise). If you need to control something in 4 directions, you need 2 motors. To power 2 motors, you need 2 complete H-bridges.
It depends how you want to steer?, the usual method for small robots is to steer like a tank, with one motor feeding each side.
the 4V voltage drop is on the DC power supply. First i set the Dc power supply to 12V....when i connect the 12V to the circuit, the Dc power supply auto drop to onli around 4V.Anyone know why this happen?
I think they will will all be partially on at any given point too.
Beginner2, every FET in existence has a certain on resistance. This means that because of the way you have your low-side FETs wired, the can both turn on at the same time. In a worse case situation, the power supply could have an almost direct connection to ground shorting it out. Another possible situation is the low-side drivers will only partially turn on causing them to dissipate a lot of heat.
Reverse EMI from the motor could also cause a number of problems.
You would have better luck controlling the high-side and low-side as 4 independent channels.
I think they look wrong way up because he used NMOS symbols for PMOS transistors. He does have the source/substrate tied to VCC, as a PMOS should be.
That doesn't mean this will work. Has anyone tried this? Let's say I have both NPNs off, so that the circuit is idle (see annotated schematic below). Now, if I turn on Q1, M1 will turn on first. It seems to me that M4 would turn on next, preventing M2 from briefly turning on. This would avoid the shoot-through problem alluded to by phalanx. The programmer would have to put in some dead time between turn-off of Q1 and turn-on of Q2 to avoid the other possible cause of shoot-through.
This configuration does not allow for shorting out the motor, which I believe is useful for braking, but it may not be necessary. This would require four control inputs.
I have to design a motor circuit which is able to move in forward, backward, left and right directions.(the circuit will be mounted on a control car)
the movemnt of this motor circuit will be control at the PC side through an user interface created using VB6.0. When instructions is given in the PC, for example, when i click on the interface at PC side to order the car the move left, instruction will be sending out from PC to the motor circuits through a 89C52 uC(The uC will be written using assembly language). When the uC receive the "left" instruction, it will turn on certain part of the motor circuits to give the left movement.
the car is a remote control car. But i wont use the remote control that comes with the car to control the car movement. Instead i want to control the car movement using interface at PC side through 89C52 uC.
the car is a remote control car. But i wont use the remote control that comes with the car to control the car movement. Instead i want to control the car movement using interface at PC side through 89C52 uC.