Smoking Motor Drive parts

The name of the pictureThe name of the pictureThe name of the pictureClash Royale CLAN TAG#URR8PPP











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I have the attached schematic. It seems to work and do what it needs to do, but it only works a few times then smokes the P channel mosfet (fqp27p06). It actually works for a bit before it smokes.



I have a 12v motor that is ran from a GPIO pin to turn on the 12v system. The P channel mosfet suppose to help with the active braking, which does seem to work (a few times). I am very new to this. Come someone tell me what I should add to quit smoking parts?





schematic





simulate this circuit – Schematic created using CircuitLab










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  • the motor actually has two limit sensors attached to it. When the sensor gets hit by the motor flag, it turns the 5v off on the motor and the circuit helps stop the flag within the sensor. the motor is then turned back on and the cycle starts again.
    – mScientist
    1 hour ago






  • 1




    Doesn't that info belong in the question rather than in the comments? There's an edit link under your question. What do you mean by a flag?
    – Transistor
    1 hour ago











  • What is the DCR of the motor and total kinetic energy when brake activated?
    – Tony EE rocketscientist
    1 hour ago










  • Your schematic is upside down.
    – Harry Svensson
    14 mins ago














up vote
1
down vote

favorite
1












I have the attached schematic. It seems to work and do what it needs to do, but it only works a few times then smokes the P channel mosfet (fqp27p06). It actually works for a bit before it smokes.



I have a 12v motor that is ran from a GPIO pin to turn on the 12v system. The P channel mosfet suppose to help with the active braking, which does seem to work (a few times). I am very new to this. Come someone tell me what I should add to quit smoking parts?





schematic





simulate this circuit – Schematic created using CircuitLab










share|improve this question























  • the motor actually has two limit sensors attached to it. When the sensor gets hit by the motor flag, it turns the 5v off on the motor and the circuit helps stop the flag within the sensor. the motor is then turned back on and the cycle starts again.
    – mScientist
    1 hour ago






  • 1




    Doesn't that info belong in the question rather than in the comments? There's an edit link under your question. What do you mean by a flag?
    – Transistor
    1 hour ago











  • What is the DCR of the motor and total kinetic energy when brake activated?
    – Tony EE rocketscientist
    1 hour ago










  • Your schematic is upside down.
    – Harry Svensson
    14 mins ago












up vote
1
down vote

favorite
1









up vote
1
down vote

favorite
1






1





I have the attached schematic. It seems to work and do what it needs to do, but it only works a few times then smokes the P channel mosfet (fqp27p06). It actually works for a bit before it smokes.



I have a 12v motor that is ran from a GPIO pin to turn on the 12v system. The P channel mosfet suppose to help with the active braking, which does seem to work (a few times). I am very new to this. Come someone tell me what I should add to quit smoking parts?





schematic





simulate this circuit – Schematic created using CircuitLab










share|improve this question















I have the attached schematic. It seems to work and do what it needs to do, but it only works a few times then smokes the P channel mosfet (fqp27p06). It actually works for a bit before it smokes.



I have a 12v motor that is ran from a GPIO pin to turn on the 12v system. The P channel mosfet suppose to help with the active braking, which does seem to work (a few times). I am very new to this. Come someone tell me what I should add to quit smoking parts?





schematic





simulate this circuit – Schematic created using CircuitLab







mosfet






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited 2 hours ago

























asked 2 hours ago









mScientist

336




336











  • the motor actually has two limit sensors attached to it. When the sensor gets hit by the motor flag, it turns the 5v off on the motor and the circuit helps stop the flag within the sensor. the motor is then turned back on and the cycle starts again.
    – mScientist
    1 hour ago






  • 1




    Doesn't that info belong in the question rather than in the comments? There's an edit link under your question. What do you mean by a flag?
    – Transistor
    1 hour ago











  • What is the DCR of the motor and total kinetic energy when brake activated?
    – Tony EE rocketscientist
    1 hour ago










  • Your schematic is upside down.
    – Harry Svensson
    14 mins ago
















  • the motor actually has two limit sensors attached to it. When the sensor gets hit by the motor flag, it turns the 5v off on the motor and the circuit helps stop the flag within the sensor. the motor is then turned back on and the cycle starts again.
    – mScientist
    1 hour ago






  • 1




    Doesn't that info belong in the question rather than in the comments? There's an edit link under your question. What do you mean by a flag?
    – Transistor
    1 hour ago











  • What is the DCR of the motor and total kinetic energy when brake activated?
    – Tony EE rocketscientist
    1 hour ago










  • Your schematic is upside down.
    – Harry Svensson
    14 mins ago















the motor actually has two limit sensors attached to it. When the sensor gets hit by the motor flag, it turns the 5v off on the motor and the circuit helps stop the flag within the sensor. the motor is then turned back on and the cycle starts again.
– mScientist
1 hour ago




the motor actually has two limit sensors attached to it. When the sensor gets hit by the motor flag, it turns the 5v off on the motor and the circuit helps stop the flag within the sensor. the motor is then turned back on and the cycle starts again.
– mScientist
1 hour ago




1




1




Doesn't that info belong in the question rather than in the comments? There's an edit link under your question. What do you mean by a flag?
– Transistor
1 hour ago





Doesn't that info belong in the question rather than in the comments? There's an edit link under your question. What do you mean by a flag?
– Transistor
1 hour ago













What is the DCR of the motor and total kinetic energy when brake activated?
– Tony EE rocketscientist
1 hour ago




What is the DCR of the motor and total kinetic energy when brake activated?
– Tony EE rocketscientist
1 hour ago












Your schematic is upside down.
– Harry Svensson
14 mins ago




Your schematic is upside down.
– Harry Svensson
14 mins ago










3 Answers
3






active

oldest

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up vote
4
down vote















schematic





simulate this circuit – Schematic created using CircuitLab



Figure 1. Redrawing in the conventional schematic layout (positive rail on top, ground on bottom with current generally flowing from top to bottom) aids comprehension.



enter image description here



Figure 2. Extract from the FQP27P06 datasheet.



Note that this device will turn on when the gate is about 3 V below the drain voltage. With a max of only 5 V available on the drain (from the GPIO) the transistor can never turn off. When M3 turns on you get "shoot-through" from the 12 V supply to ground and the high currents are destroying your MOSFETs.



Notice how much more easy it is to visualise the voltages and shoot-through when the circuit is drawn correctly.






share|improve this answer



























    up vote
    2
    down vote













    I don't believe that your PFET is ever being turned OFF which may be the cause of your FET smoking. Looking at the your PFET datasheet, the gate-to-source (VGS) turn ON range is -2->-4V. Your circuit never provides a voltage difference of the source (12V) to your gate (5V or 0V) in which the gate would be OFF.



    GPIO pin = 5V: Vgs = 5V - 12V = -7V 
    GPIO pin = 0V: Vgs = 0V - 12V = -12V


    Take a look at figure 2 in the datasheet. You will notice that the drain current will always be at its maximum given the above conditions. You need to either lower your drain voltage of 12V, or raise your GPIO voltage so that you can properly turn OFF your PFET.



    Your NFET could also be replaced with a more suitable FET. Look at its datasheet, particularly figure 2. At 5V, the maximum drain current is not achieved.



    The FETs you have chosen have internal diodes that help protect it from the quick shutoff current. The 1N4001 is much too slow to cause any noticeable difference in the circuit operation since the other diodes will react faster. It won't hurt to place a beefier fast-acting one in its place though.



    Be sure to place some small decoupling capacitors next to your FETs drain-to-source pins as well as across the motor itself. Placing a large capacitor next to the power source is advisable as well.



    Your circuit is also drawn a bit awkward. Try placing the voltage sources highest in the schematic and the ground terminals lowest. Essentially, you should mirror your circuit over the x-axis in its current form.






    share|improve this answer








    New contributor




    User3219 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.
























      up vote
      0
      down vote













      It seems to be under-designed. The Motor has a TBD DCR (to be determined DC resistance) spec and the inertial kinetic energy is TBD, therefore, the amount of energy that must be dumped depends on RdsOn and the time to absorb the kinetic energy in the winding and switch loss.



      If NFET RdsOn is 0.045Ω approx and PFET maybe 50% higher ( est.) then the power consumed in the FET for braking is much higher as the NFET has much more time to build up kinetic energy while the brake shorts out all motors back EMF with the kinetic energy now the driving force. $Pd=12V^2/(DCR+R_dsO_n)$ for some duration determined by Force, mass and deacceleration . The 12V BEMF of 12V drops with speed to 0. This can be simplified but, not at this moment.



      Unless there is current limiting with external brake dummy load of X milliOhms or a PFET rated for 10x the motor rated current resulting in an RdsOn much lower than the NFET that acts as a low side switch to drive the motor over a longer period of time, the PFET will always get hotter.



      Of course, heat increases the RdsON and this can lead to thermal runaway in a brake FET. pfft. THus adequate power dissipation and thermal resistance calculations are needed to ensure it does not overheat.



      Without any details requested, for Kinetic energy, motor DCR and Rja thermal resistance, no design can be done properly.



      Naturally, there must be deadtime and duty factor considered in the rep. rate of these alternate seeks and perhaps temperature sensors to protect the design from failure ( and smoking parts )



      p.s. Cn you learn to draw like the rest of the world with Positive Voltage supplies above 0V.






      share|improve this answer






















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        3 Answers
        3






        active

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        3 Answers
        3






        active

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        active

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        up vote
        4
        down vote















        schematic





        simulate this circuit – Schematic created using CircuitLab



        Figure 1. Redrawing in the conventional schematic layout (positive rail on top, ground on bottom with current generally flowing from top to bottom) aids comprehension.



        enter image description here



        Figure 2. Extract from the FQP27P06 datasheet.



        Note that this device will turn on when the gate is about 3 V below the drain voltage. With a max of only 5 V available on the drain (from the GPIO) the transistor can never turn off. When M3 turns on you get "shoot-through" from the 12 V supply to ground and the high currents are destroying your MOSFETs.



        Notice how much more easy it is to visualise the voltages and shoot-through when the circuit is drawn correctly.






        share|improve this answer
























          up vote
          4
          down vote















          schematic





          simulate this circuit – Schematic created using CircuitLab



          Figure 1. Redrawing in the conventional schematic layout (positive rail on top, ground on bottom with current generally flowing from top to bottom) aids comprehension.



          enter image description here



          Figure 2. Extract from the FQP27P06 datasheet.



          Note that this device will turn on when the gate is about 3 V below the drain voltage. With a max of only 5 V available on the drain (from the GPIO) the transistor can never turn off. When M3 turns on you get "shoot-through" from the 12 V supply to ground and the high currents are destroying your MOSFETs.



          Notice how much more easy it is to visualise the voltages and shoot-through when the circuit is drawn correctly.






          share|improve this answer






















            up vote
            4
            down vote










            up vote
            4
            down vote











            schematic





            simulate this circuit – Schematic created using CircuitLab



            Figure 1. Redrawing in the conventional schematic layout (positive rail on top, ground on bottom with current generally flowing from top to bottom) aids comprehension.



            enter image description here



            Figure 2. Extract from the FQP27P06 datasheet.



            Note that this device will turn on when the gate is about 3 V below the drain voltage. With a max of only 5 V available on the drain (from the GPIO) the transistor can never turn off. When M3 turns on you get "shoot-through" from the 12 V supply to ground and the high currents are destroying your MOSFETs.



            Notice how much more easy it is to visualise the voltages and shoot-through when the circuit is drawn correctly.






            share|improve this answer














            schematic





            simulate this circuit – Schematic created using CircuitLab



            Figure 1. Redrawing in the conventional schematic layout (positive rail on top, ground on bottom with current generally flowing from top to bottom) aids comprehension.



            enter image description here



            Figure 2. Extract from the FQP27P06 datasheet.



            Note that this device will turn on when the gate is about 3 V below the drain voltage. With a max of only 5 V available on the drain (from the GPIO) the transistor can never turn off. When M3 turns on you get "shoot-through" from the 12 V supply to ground and the high currents are destroying your MOSFETs.



            Notice how much more easy it is to visualise the voltages and shoot-through when the circuit is drawn correctly.







            share|improve this answer












            share|improve this answer



            share|improve this answer










            answered 1 hour ago









            Transistor

            74.3k572162




            74.3k572162






















                up vote
                2
                down vote













                I don't believe that your PFET is ever being turned OFF which may be the cause of your FET smoking. Looking at the your PFET datasheet, the gate-to-source (VGS) turn ON range is -2->-4V. Your circuit never provides a voltage difference of the source (12V) to your gate (5V or 0V) in which the gate would be OFF.



                GPIO pin = 5V: Vgs = 5V - 12V = -7V 
                GPIO pin = 0V: Vgs = 0V - 12V = -12V


                Take a look at figure 2 in the datasheet. You will notice that the drain current will always be at its maximum given the above conditions. You need to either lower your drain voltage of 12V, or raise your GPIO voltage so that you can properly turn OFF your PFET.



                Your NFET could also be replaced with a more suitable FET. Look at its datasheet, particularly figure 2. At 5V, the maximum drain current is not achieved.



                The FETs you have chosen have internal diodes that help protect it from the quick shutoff current. The 1N4001 is much too slow to cause any noticeable difference in the circuit operation since the other diodes will react faster. It won't hurt to place a beefier fast-acting one in its place though.



                Be sure to place some small decoupling capacitors next to your FETs drain-to-source pins as well as across the motor itself. Placing a large capacitor next to the power source is advisable as well.



                Your circuit is also drawn a bit awkward. Try placing the voltage sources highest in the schematic and the ground terminals lowest. Essentially, you should mirror your circuit over the x-axis in its current form.






                share|improve this answer








                New contributor




                User3219 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                Check out our Code of Conduct.





















                  up vote
                  2
                  down vote













                  I don't believe that your PFET is ever being turned OFF which may be the cause of your FET smoking. Looking at the your PFET datasheet, the gate-to-source (VGS) turn ON range is -2->-4V. Your circuit never provides a voltage difference of the source (12V) to your gate (5V or 0V) in which the gate would be OFF.



                  GPIO pin = 5V: Vgs = 5V - 12V = -7V 
                  GPIO pin = 0V: Vgs = 0V - 12V = -12V


                  Take a look at figure 2 in the datasheet. You will notice that the drain current will always be at its maximum given the above conditions. You need to either lower your drain voltage of 12V, or raise your GPIO voltage so that you can properly turn OFF your PFET.



                  Your NFET could also be replaced with a more suitable FET. Look at its datasheet, particularly figure 2. At 5V, the maximum drain current is not achieved.



                  The FETs you have chosen have internal diodes that help protect it from the quick shutoff current. The 1N4001 is much too slow to cause any noticeable difference in the circuit operation since the other diodes will react faster. It won't hurt to place a beefier fast-acting one in its place though.



                  Be sure to place some small decoupling capacitors next to your FETs drain-to-source pins as well as across the motor itself. Placing a large capacitor next to the power source is advisable as well.



                  Your circuit is also drawn a bit awkward. Try placing the voltage sources highest in the schematic and the ground terminals lowest. Essentially, you should mirror your circuit over the x-axis in its current form.






                  share|improve this answer








                  New contributor




                  User3219 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                  Check out our Code of Conduct.



















                    up vote
                    2
                    down vote










                    up vote
                    2
                    down vote









                    I don't believe that your PFET is ever being turned OFF which may be the cause of your FET smoking. Looking at the your PFET datasheet, the gate-to-source (VGS) turn ON range is -2->-4V. Your circuit never provides a voltage difference of the source (12V) to your gate (5V or 0V) in which the gate would be OFF.



                    GPIO pin = 5V: Vgs = 5V - 12V = -7V 
                    GPIO pin = 0V: Vgs = 0V - 12V = -12V


                    Take a look at figure 2 in the datasheet. You will notice that the drain current will always be at its maximum given the above conditions. You need to either lower your drain voltage of 12V, or raise your GPIO voltage so that you can properly turn OFF your PFET.



                    Your NFET could also be replaced with a more suitable FET. Look at its datasheet, particularly figure 2. At 5V, the maximum drain current is not achieved.



                    The FETs you have chosen have internal diodes that help protect it from the quick shutoff current. The 1N4001 is much too slow to cause any noticeable difference in the circuit operation since the other diodes will react faster. It won't hurt to place a beefier fast-acting one in its place though.



                    Be sure to place some small decoupling capacitors next to your FETs drain-to-source pins as well as across the motor itself. Placing a large capacitor next to the power source is advisable as well.



                    Your circuit is also drawn a bit awkward. Try placing the voltage sources highest in the schematic and the ground terminals lowest. Essentially, you should mirror your circuit over the x-axis in its current form.






                    share|improve this answer








                    New contributor




                    User3219 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                    Check out our Code of Conduct.









                    I don't believe that your PFET is ever being turned OFF which may be the cause of your FET smoking. Looking at the your PFET datasheet, the gate-to-source (VGS) turn ON range is -2->-4V. Your circuit never provides a voltage difference of the source (12V) to your gate (5V or 0V) in which the gate would be OFF.



                    GPIO pin = 5V: Vgs = 5V - 12V = -7V 
                    GPIO pin = 0V: Vgs = 0V - 12V = -12V


                    Take a look at figure 2 in the datasheet. You will notice that the drain current will always be at its maximum given the above conditions. You need to either lower your drain voltage of 12V, or raise your GPIO voltage so that you can properly turn OFF your PFET.



                    Your NFET could also be replaced with a more suitable FET. Look at its datasheet, particularly figure 2. At 5V, the maximum drain current is not achieved.



                    The FETs you have chosen have internal diodes that help protect it from the quick shutoff current. The 1N4001 is much too slow to cause any noticeable difference in the circuit operation since the other diodes will react faster. It won't hurt to place a beefier fast-acting one in its place though.



                    Be sure to place some small decoupling capacitors next to your FETs drain-to-source pins as well as across the motor itself. Placing a large capacitor next to the power source is advisable as well.



                    Your circuit is also drawn a bit awkward. Try placing the voltage sources highest in the schematic and the ground terminals lowest. Essentially, you should mirror your circuit over the x-axis in its current form.







                    share|improve this answer








                    New contributor




                    User3219 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                    Check out our Code of Conduct.









                    share|improve this answer



                    share|improve this answer






                    New contributor




                    User3219 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                    Check out our Code of Conduct.









                    answered 1 hour ago









                    User3219

                    212




                    212




                    New contributor




                    User3219 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                    Check out our Code of Conduct.





                    New contributor





                    User3219 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                    Check out our Code of Conduct.






                    User3219 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                    Check out our Code of Conduct.




















                        up vote
                        0
                        down vote













                        It seems to be under-designed. The Motor has a TBD DCR (to be determined DC resistance) spec and the inertial kinetic energy is TBD, therefore, the amount of energy that must be dumped depends on RdsOn and the time to absorb the kinetic energy in the winding and switch loss.



                        If NFET RdsOn is 0.045Ω approx and PFET maybe 50% higher ( est.) then the power consumed in the FET for braking is much higher as the NFET has much more time to build up kinetic energy while the brake shorts out all motors back EMF with the kinetic energy now the driving force. $Pd=12V^2/(DCR+R_dsO_n)$ for some duration determined by Force, mass and deacceleration . The 12V BEMF of 12V drops with speed to 0. This can be simplified but, not at this moment.



                        Unless there is current limiting with external brake dummy load of X milliOhms or a PFET rated for 10x the motor rated current resulting in an RdsOn much lower than the NFET that acts as a low side switch to drive the motor over a longer period of time, the PFET will always get hotter.



                        Of course, heat increases the RdsON and this can lead to thermal runaway in a brake FET. pfft. THus adequate power dissipation and thermal resistance calculations are needed to ensure it does not overheat.



                        Without any details requested, for Kinetic energy, motor DCR and Rja thermal resistance, no design can be done properly.



                        Naturally, there must be deadtime and duty factor considered in the rep. rate of these alternate seeks and perhaps temperature sensors to protect the design from failure ( and smoking parts )



                        p.s. Cn you learn to draw like the rest of the world with Positive Voltage supplies above 0V.






                        share|improve this answer


























                          up vote
                          0
                          down vote













                          It seems to be under-designed. The Motor has a TBD DCR (to be determined DC resistance) spec and the inertial kinetic energy is TBD, therefore, the amount of energy that must be dumped depends on RdsOn and the time to absorb the kinetic energy in the winding and switch loss.



                          If NFET RdsOn is 0.045Ω approx and PFET maybe 50% higher ( est.) then the power consumed in the FET for braking is much higher as the NFET has much more time to build up kinetic energy while the brake shorts out all motors back EMF with the kinetic energy now the driving force. $Pd=12V^2/(DCR+R_dsO_n)$ for some duration determined by Force, mass and deacceleration . The 12V BEMF of 12V drops with speed to 0. This can be simplified but, not at this moment.



                          Unless there is current limiting with external brake dummy load of X milliOhms or a PFET rated for 10x the motor rated current resulting in an RdsOn much lower than the NFET that acts as a low side switch to drive the motor over a longer period of time, the PFET will always get hotter.



                          Of course, heat increases the RdsON and this can lead to thermal runaway in a brake FET. pfft. THus adequate power dissipation and thermal resistance calculations are needed to ensure it does not overheat.



                          Without any details requested, for Kinetic energy, motor DCR and Rja thermal resistance, no design can be done properly.



                          Naturally, there must be deadtime and duty factor considered in the rep. rate of these alternate seeks and perhaps temperature sensors to protect the design from failure ( and smoking parts )



                          p.s. Cn you learn to draw like the rest of the world with Positive Voltage supplies above 0V.






                          share|improve this answer
























                            up vote
                            0
                            down vote










                            up vote
                            0
                            down vote









                            It seems to be under-designed. The Motor has a TBD DCR (to be determined DC resistance) spec and the inertial kinetic energy is TBD, therefore, the amount of energy that must be dumped depends on RdsOn and the time to absorb the kinetic energy in the winding and switch loss.



                            If NFET RdsOn is 0.045Ω approx and PFET maybe 50% higher ( est.) then the power consumed in the FET for braking is much higher as the NFET has much more time to build up kinetic energy while the brake shorts out all motors back EMF with the kinetic energy now the driving force. $Pd=12V^2/(DCR+R_dsO_n)$ for some duration determined by Force, mass and deacceleration . The 12V BEMF of 12V drops with speed to 0. This can be simplified but, not at this moment.



                            Unless there is current limiting with external brake dummy load of X milliOhms or a PFET rated for 10x the motor rated current resulting in an RdsOn much lower than the NFET that acts as a low side switch to drive the motor over a longer period of time, the PFET will always get hotter.



                            Of course, heat increases the RdsON and this can lead to thermal runaway in a brake FET. pfft. THus adequate power dissipation and thermal resistance calculations are needed to ensure it does not overheat.



                            Without any details requested, for Kinetic energy, motor DCR and Rja thermal resistance, no design can be done properly.



                            Naturally, there must be deadtime and duty factor considered in the rep. rate of these alternate seeks and perhaps temperature sensors to protect the design from failure ( and smoking parts )



                            p.s. Cn you learn to draw like the rest of the world with Positive Voltage supplies above 0V.






                            share|improve this answer














                            It seems to be under-designed. The Motor has a TBD DCR (to be determined DC resistance) spec and the inertial kinetic energy is TBD, therefore, the amount of energy that must be dumped depends on RdsOn and the time to absorb the kinetic energy in the winding and switch loss.



                            If NFET RdsOn is 0.045Ω approx and PFET maybe 50% higher ( est.) then the power consumed in the FET for braking is much higher as the NFET has much more time to build up kinetic energy while the brake shorts out all motors back EMF with the kinetic energy now the driving force. $Pd=12V^2/(DCR+R_dsO_n)$ for some duration determined by Force, mass and deacceleration . The 12V BEMF of 12V drops with speed to 0. This can be simplified but, not at this moment.



                            Unless there is current limiting with external brake dummy load of X milliOhms or a PFET rated for 10x the motor rated current resulting in an RdsOn much lower than the NFET that acts as a low side switch to drive the motor over a longer period of time, the PFET will always get hotter.



                            Of course, heat increases the RdsON and this can lead to thermal runaway in a brake FET. pfft. THus adequate power dissipation and thermal resistance calculations are needed to ensure it does not overheat.



                            Without any details requested, for Kinetic energy, motor DCR and Rja thermal resistance, no design can be done properly.



                            Naturally, there must be deadtime and duty factor considered in the rep. rate of these alternate seeks and perhaps temperature sensors to protect the design from failure ( and smoking parts )



                            p.s. Cn you learn to draw like the rest of the world with Positive Voltage supplies above 0V.







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                            edited 16 mins ago

























                            answered 21 mins ago









                            Tony EE rocketscientist

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