MOSFET Voltage to Current Converter

[RareCliche]

Greetings! I am currently working on a Bandgap reference circuit with programmable DAC. I have been able to produce a Voltage reference but my DAC requires a current input. I have searched for a converter and found none that make use of just MOSFET as it was the limitation of my study.

Is it possible to make a voltage to current converter or convert Vref to Iref with just the use of MOSFET?
Or are there any other method I can use to input current in my DAC?

Help will be much appreciated!

 

[arthorios]

What is the goal/target specs of your circuit? Do you need both current and voltage DACs?
You can realize a voltage-to-current converter by forcing your Vbg on a resistor (using feedback). This can be implemented with a simple amplifier and a pass transistor. On the other hand, bandgaps always have a core current source, so this could also be used for your current DAC if low tempco is not a requirement.

It's always good to show the schematics of your circuit to get a better idea of what you want to achieve. Hope this helps.

 

[RareCliche]

What is the goal/target specs of your circuit? Do you need both current and voltage DACs?
You can realize a voltage-to-current converter by forcing your Vbg on a resistor (using feedback). This can be implemented with a simple amplifier and a pass transistor. On the other hand, bandgaps always have a core current source, so this could also be used for your current DAC if low tempco is not a requirement.

It's always good to show the schematics of your circuit to get a better idea of what you want to achieve. Hope this helps.

Thank you for your reply. The output voltage of our BGR has to be around 300-800mV. I will take a look on the simple amplifier and pass transistor.

I'm not really familiar with the core current source of the BGR so I do not know how to make use of it.
can you tell me more about it?

here is our BGR for reference:

 

[arthorios]

What are the target specs of your voltage reference? From your schematics, it seems that the bias currents are not well defined, and your circuit operates in subthreshold. Is low voltage operation a requirement? If not, I suggest you use a much simpler structure to generate the required 300-800mV output. You can search for the well-known Banba sub-bandgap voltage reference for that. It can provide you with both voltage and current references.

 

[RareCliche]

What are the target specs of your voltage reference? From your schematics, it seems that the bias currents are not well defined, and your circuit operates in subthreshold. Is low voltage operation a requirement? If not, I suggest you use a much simpler structure to generate the required 300-800mV output. You can search for the well-known Banba sub-bandgap voltage reference for that. It can provide you with both voltage and current references.

Our voltage reference aims to operate in low voltage and in Full MOSFET