hi
i make 4 axis cnc machine so,
i use 4 stepper motor 4.6A i make drivers for every motor

and this site have every detail
http://www.instructables.com/id/Easy-to-build-CNC-Mill-Stepper-Motor-and-Driver-ci/CEVVKDOH27LSH4K
i use 60n06 as mosfet
i use unipolar stepper motor 6 wires
i make circuit for limitation the current

this site for details
http://www.divms.uiowa.edu/~jones/step/current.html
i have some problem problem
1- i can know how to calculate R2
2- 60n06 heated so much
3- voltage across motor only 2.5v i use 24v power supply & voltage come out from r1=17v
i need to know why voltage be like that
please help

 

Here is a more legible schematic.

 

Here is a more legible schematic.

thanks
do you know best mosfet can i used for 12v & 5A stepper motor

 

thanks
do you know best mosfet can i used for 12v & 5A stepper motor

I am not an expert, but I have used IRF44N, and IRL44N (when logic level drive is required.) There are others here with more experience.

 

I am not an expert, but I have used IRF44N, and IRL44N (when logic level drive is required.) There are others here with more experience.

i used irf 840 before 60n06
it is heated more than 60n06
i need high power mosfet

 

i measure the voltage out from mosfet it 7v while input power supply 24v
when i connect motor and limitation circuit voltage be 2.5v
i need to know why voltage be like that
please help
mosfet in circuit work as switch why regulate voltage .

 

You need to use a logic level mosfet.. Not a standard one.

 

i use 24v power supply

How much current can this power supply provide?

i use 4 stepper motor 4.6A i make drivers for every motor

Is that 4.6a per motor, or 4.6a total?

 

You need to use a logic level mosfet.. Not a standard one.

i used 60n06 logic level mosfet
i have 3055 &15n06 logic mosfet do you think it will work fine

 

datasheet for 60n06 logic level mosfet
View attachment NTP60N06L-D.PDF

 

Why not change the zener diode to a 12V one and then a standard Nmosfet can be used?

How are you measuring the output voltage of the mosfet when it should be connected to ground?

With the CD4016 and CD4028 providing the stepper logic in this circuit, there is no amperage control to the motors. This is the reason to use regular step motor divers for a circuit like this. Fewer components and more control of the motor is the result of using a stepper driver chip.

 

first think i need to understand zener diode here do what
i measuring the output voltage of the mosfet between output of mosfet and +dc when gate open
i use this drive (very simple ) only problem i have with mosfet
i make current limitation circuit it run nice
but problem with voltage
i use 24v power supply and voltage across motor only 2v

 

The zener in your schematic allows only what ever voltage it is rated at to the rest of the circuit. By changing the zener value it changes the voltage available to the circuit. The chips you have chosen will work at 12V and that will also give 12V for the mosfet gates.

Still don't understand how you are measuring "mosfet output". The mosfets are not "outputting" anything. The S(source) is connected to ground/common, or should be in a unipolar stepper drive. So when measuring from +V to ground that should be your supply voltage.

 

i change zener but nothing change
i measure the voltage out from ic 4028 to mosfet 1.5v
that is make mosfet heated so much and cut voltage
i will use operational amplifier to make it 5v
i measuring voltage between output of mosfet and +v supply
resistance in mosfet still high because voltage in gate not 5v
and cut voltage to 7v
do you know best amplifier can i use for (27v power supply)
max v for 741 is 22v
thanks

 

You should try disconnecting the 4028 outputs from the MOSFET gates (connecting the gates to the source terminal temporarily to protect them) and then measure the voltage at the output of the 4028. You should then see the output voltage rising to the same as Vdd when that particular output is selected.

One of the problems is that you are using MOSFETs with a large Qg (total gate charge) and are trying to charge/discharge them from a 4000 series CMOS part, namely the 4028. These CMOS parts are efficient compared to, say, the old TTL, but rather anemic - this results in the MOSFET turn-on and turn-off times being quite slow. In this situation, having slow turn-ON times isn't so bad, as it will take awhile for the current flow to build through the motor when it's first turned on. It's the slow turn-off time where heat is generated.

It's also possible that you might be experiencing ringing on the gates, as the schematic doesn't have gate resistors shown, nor does it show bypass capacitors for the CMOS ICs.

When a MOSFET fails, it frequently fails with the gate shorted to the drain. This failure mode would likely destroy your 4028 as well as the MOSFET. This is why I asked you in the beginning to see if the voltage on the 4028 outputs comes up to Vdd or not.

 

i disconnecting the 4028 outputs from the MOSFET gates
i measure the voltage at the output of the 4028 1.5v
vdd = 6v
so 4028 destroy or i need to amplified voltage form it to mosfet
what is number of mosfet can i use with 4028 and work well ?

 

i changing 4028 &4516
and have same result 1.5v output from 4028 & vdd=6v

 

OK then, check your wiring because something is causing the outputs of the 4028 to get loaded excessively. If your Vdd=6v, you should see that on the output.

 

i make the circuit again on text board vdd=6v(4028&4516) vout from 4516 to 4028 = 6v
vout from 4028 = 1.5v
i connect wire exactly like photo

 

i take signal from 4028 to 741 and make it out 5.5 v by non inverting amplifier connection

but if i connected to mosfet 60n06 it heated so so much
is this because the different in speed between 4028 & 60n06
or what