I would like my power rail be from the power supply I designed. Basically VDD not be from default configuration. How do I do this?
Yves
Changing Default power line
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jayanthd2k17
- Professional User
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Re: Changing Default power line
By default the power line hasyves-michel wrote:I would like my power rail be from the power supply I designed. Basically VDD not be from default configuration. How do I do this?
Yves
GND = 0V
VCC/VDD = 5V
VEE = -5V
If you have a say PIC18F model then change its Hidden pins connections to say VDD1 and VSS1.
In power rail settings create new entries like VDD_1 = 5V and VSS_1 = 0V and add VDD1 to VDD_1 and VSS1 to VSS_1.
Re: Changing Default power line
For PCB layout purposes simply assign your own power supply output to a POWER TERMINAL by naming it as VDD or VCC as well.yves-michel wrote:I would like my power rail be from the power supply I designed. Basically VDD not be from default configuration. How do I do this?
Yves
This creates the needed connectivity between your own power supply line and VDD power rail.
Kind regards,
Ettore Arena - Labcenter Electronics.
Ettore Arena - Labcenter Electronics.
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yves-michel
Re: Changing Default power line
dear all
Let me explain what I want to do in simulation. I have set a power supply that has a shutdown pin. I have simulated an on/off circuit using a single button. I do not want the supply to be a specific voltage. The supply to the processor comes only when the button is pressed and the processor holds the SHDN high. When the button is pressed again a sense signal brings the hold down and turns off the voltage controller. So my question is how do I set the power configuration without a specific volage? I have attached the schematic with its hex code. I have tried many configurations but not getting it right. Many thanks for your time.
Regards,
Yves
Proteus 8.6
Let me explain what I want to do in simulation. I have set a power supply that has a shutdown pin. I have simulated an on/off circuit using a single button. I do not want the supply to be a specific voltage. The supply to the processor comes only when the button is pressed and the processor holds the SHDN high. When the button is pressed again a sense signal brings the hold down and turns off the voltage controller. So my question is how do I set the power configuration without a specific volage? I have attached the schematic with its hex code. I have tried many configurations but not getting it right. Many thanks for your time.
Regards,
Yves
Proteus 8.6
- Attachments
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- 1 button on-off power supply test.zip
- (104.18 KiB) Downloaded 59 times
Re: Changing Default power line
Hi Yves, this has been explained several times.
The power rail for micro-controllers, logic gates and any "pure" digital model as well cannot be switched on and off, as the Proteus DSIM (digital simulator) enables VCC/VDD voltage automatically at simulation start-up. Telling that in different words, it means that you cannot simulate any brown-out condition or other generic action at power off for digital models.
Technically speaking, a simulation of a generic digital circuit is a combination of three status modes: the BOOT mode, which happens at the very first timestep, the SETTLE mode where all initial conditions (logical states) propagate in the circuit and, finally, NORMAL mode, which is the ordinary simulation timesteps. The digital simulator DSIM must consider the power rail always on at the BOOT mode, otherwise the SETTLE mode cannot be initiated and the initial conditions do not propagate, and in such the case the NORMAL simulation cannot be take place. It's obviously more complex than that but it should give you an generic idea about how the things work.
That's, for instance, the reason as to why the brown-out features are not supported in all the micro-controller simulation models.
For those (very) few applications where any action at the power off and on have to be investigated then, I think, that only an hardware prototype will do for the purpose.
What above is for simulation purposes. For PCB layout purposes my previous recommendation is still helpful.
The power rail for micro-controllers, logic gates and any "pure" digital model as well cannot be switched on and off, as the Proteus DSIM (digital simulator) enables VCC/VDD voltage automatically at simulation start-up. Telling that in different words, it means that you cannot simulate any brown-out condition or other generic action at power off for digital models.
Technically speaking, a simulation of a generic digital circuit is a combination of three status modes: the BOOT mode, which happens at the very first timestep, the SETTLE mode where all initial conditions (logical states) propagate in the circuit and, finally, NORMAL mode, which is the ordinary simulation timesteps. The digital simulator DSIM must consider the power rail always on at the BOOT mode, otherwise the SETTLE mode cannot be initiated and the initial conditions do not propagate, and in such the case the NORMAL simulation cannot be take place. It's obviously more complex than that but it should give you an generic idea about how the things work.
That's, for instance, the reason as to why the brown-out features are not supported in all the micro-controller simulation models.
For those (very) few applications where any action at the power off and on have to be investigated then, I think, that only an hardware prototype will do for the purpose.
What above is for simulation purposes. For PCB layout purposes my previous recommendation is still helpful.
Kind regards,
Ettore Arena - Labcenter Electronics.
Ettore Arena - Labcenter Electronics.
-
yves-michel
Re: Changing Default power line
Thank you, Ettore,
So if I well understood you, it cant be simulated the way I would like to do on the other hand One I managed to demonstrate it is was by tying the MCLR pin to my power supply which I named "Power control" and it did what what it was supposed to do.
Regards,
Yves
So if I well understood you, it cant be simulated the way I would like to do on the other hand One I managed to demonstrate it is was by tying the MCLR pin to my power supply which I named "Power control" and it did what what it was supposed to do.
Regards,
Yves