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I would like to convert 5V rail I have on PCB to ±12V. Existing solution is using boost converter 5V to 12V, and a buck for 5V to -12V. This feels bulky for what it's needed - here are the requirem...
Question
chargepump
#4: Post edited
Converting 5V to +/-12V
- Converting 5V to ±12V
I would like to convert 5V rail I have on PCB to +-12V. Existing solution is using boost converter 5V to 12V, and a buck for 5V to -12V. This feels bulky for what it's needed - here are the requirements:- - +12V and -12V rail shall serve for powering opamp only
- Ripple of the +-12V rail is not of a concern, as the opamp is used in comparator mode(something I would like to swap with the comparator in the future but keeping it for now in the design)- +12V and -12V rail should be within +-5% ie. acceptable voltage range of rail is (11.4V, 12.6V) both for positive and negative- +-12V rail shall be capable of providing no more than 5mA of current- - There is a 3V3 powered uC on board with available PWM output which could be used for charge pumps
- Everything mentioned so far asks for a charge pump, the way how I see it.
- Some options I found:
- Maxim/Analog have +5V to +-10V converter IC [MAX680/681](https://pdfserv.maximintegrated.com/en/ds/MAX680-MAX681.pdf), with VCC max of 6.2V and V+/V- being +12V/-12V in absolute maximum ratings, I feel like stretching it + it is not within acceptable voltage range- - Do a DIY charge pump using PWM uC output - haven't done this earlier so if someone could explain a concept with jellybean components that would be a useful answer as well.
- Use a standalone 5V to +-12V converter like a [Murata one](https://eu.mouser.com/datasheet/2/281/1/kdc_nmv-2941136.pdf)- - Use 2x dedicated charge pumps - 5V to 12V(to be found) and 12V to -12V([TC1044S](https://ww1.microchip.com/downloads/en/DeviceDoc/21348a.pdf))
- Questions:
- Could charge pump 5V to +-12V be implemented with 1xPWM output from the uC, how would the circuit look like and what would be the component values(capacitor size, diodes, etc.)?- - Are there some other way how to do this which I have not covered?
- I would like to convert 5V rail I have on PCB to ±12V. Existing solution is using boost converter 5V to 12V, and a buck for 5V to -12V. This feels bulky for what it's needed - here are the requirements:
- - +12V and -12V rail shall serve for powering opamp only
- - Ripple of the ±12V rails is not of a concern, as the opamp is used in comparator mode(something I would like to swap with the comparator in the future but keeping it for now in the design)
- - +12V and -12V rail should be within ±5% ie. acceptable voltage range of rail is (11.4V, 12.6V) both for positive and negative
- - ±12V rails shall be capable of providing no more than 5mA of current
- - There is a 3V3 powered uC on board with available PWM output which could be used for charge pumps
- Everything mentioned so far asks for a charge pump, the way how I see it.
- Some options I found:
- - Maxim/Analog have +5V to ±10V converter IC [MAX680/681](https://pdfserv.maximintegrated.com/en/ds/MAX680-MAX681.pdf), with VCC max of 6.2V and V+/V- being +12V/-12V in absolute maximum ratings, I feel like stretching it + it is not within acceptable voltage range
- - Do a DIY charge pump using PWM uC output - haven't done this earlier so if someone could explain a concept with jellybean components that would be a useful answer as well.
- - Use a standalone 5V to ±12V converter like a [Murata one](https://eu.mouser.com/datasheet/2/281/1/kdc_nmv-2941136.pdf)
- - Use 2x dedicated charge pumps - 5V to 12V(to be found) and 12V to -12V([TC1044S](https://ww1.microchip.com/downloads/en/DeviceDoc/21348a.pdf))
- Questions:
- - Could charge pump 5V to ±12V be implemented with 1xPWM output from the uC, how would the circuit look like and what would be the component values(capacitor size, diodes, etc.)?
- - Are there some other way how to do this which I have not covered?
#3: Post edited
- I would like to convert 5V rail I have on PCB to +-12V. Existing solution is using boost converter 5V to 12V, and a buck for 5V to -12V. This feels bulky for what it's needed - here are the requirements:
- - +12V and -12V rail shall serve for powering opamp only
- - Ripple of the +-12V rail is not of a concern, as the opamp is used in comparator mode(something I would like to swap with the comparator in the future but keeping it for now in the design)
- - +12V and -12V rail should be within +-5% ie. acceptable voltage range of rail is (11.4V, 12.6V) both for positive and negative
- - +-12V rail shall be capable of providing no more than 5mA of current
- - There is a 3V3 powered uC on board with available PWM output which could be used for charge pumps
- Everything mentioned so far asks for a charge pump, the way how I see it.
- Some options I found:
- - Maxim/Analog have +5V to +-10V converter IC [MAX680/681](https://pdfserv.maximintegrated.com/en/ds/MAX680-MAX681.pdf), with VCC max of 6.2V and V+/V- being +12V/-12V in absolute maximum ratings, I feel like stretching it + it is not within acceptable voltage range
- - Do a DIY charge pump using PWM uC output - haven't done this earlier so if someone could explain a concept with jellybean components that would be a useful answer as well.
- - Use a standalone 5V to +-12V converter like a [Murata one](https://eu.mouser.com/datasheet/2/281/1/kdc_nmv-2941136.pdf)
- Use 2x dedicated charge pumps - 5V to 12V and 12V to -12V([TC1044S](https://ww1.microchip.com/downloads/en/DeviceDoc/21348a.pdf))- Questions:
- - Could charge pump 5V to +-12V be implemented with 1xPWM output from the uC, how would the circuit look like and what would be the component values(capacitor size, diodes, etc.)?
- - Are there some other way how to do this which I have not covered?
- I would like to convert 5V rail I have on PCB to +-12V. Existing solution is using boost converter 5V to 12V, and a buck for 5V to -12V. This feels bulky for what it's needed - here are the requirements:
- - +12V and -12V rail shall serve for powering opamp only
- - Ripple of the +-12V rail is not of a concern, as the opamp is used in comparator mode(something I would like to swap with the comparator in the future but keeping it for now in the design)
- - +12V and -12V rail should be within +-5% ie. acceptable voltage range of rail is (11.4V, 12.6V) both for positive and negative
- - +-12V rail shall be capable of providing no more than 5mA of current
- - There is a 3V3 powered uC on board with available PWM output which could be used for charge pumps
- Everything mentioned so far asks for a charge pump, the way how I see it.
- Some options I found:
- - Maxim/Analog have +5V to +-10V converter IC [MAX680/681](https://pdfserv.maximintegrated.com/en/ds/MAX680-MAX681.pdf), with VCC max of 6.2V and V+/V- being +12V/-12V in absolute maximum ratings, I feel like stretching it + it is not within acceptable voltage range
- - Do a DIY charge pump using PWM uC output - haven't done this earlier so if someone could explain a concept with jellybean components that would be a useful answer as well.
- - Use a standalone 5V to +-12V converter like a [Murata one](https://eu.mouser.com/datasheet/2/281/1/kdc_nmv-2941136.pdf)
- - Use 2x dedicated charge pumps - 5V to 12V(to be found) and 12V to -12V([TC1044S](https://ww1.microchip.com/downloads/en/DeviceDoc/21348a.pdf))
- Questions:
- - Could charge pump 5V to +-12V be implemented with 1xPWM output from the uC, how would the circuit look like and what would be the component values(capacitor size, diodes, etc.)?
- - Are there some other way how to do this which I have not covered?
#2: Post edited
- I would like to convert 5V rail I have on PCB to +-12V. Existing solution is using boost converter 5V to 12V, and a buck for 5V to -12V. This feels bulky for what it's needed - here are the requirements:
- - +12V and -12V rail shall serve for powering opamp only
- - Ripple of the +-12V rail is not of a concern, as the opamp is used in comparator mode(something I would like to swap with the comparator in the future but keeping it for now in the design)
- - +12V and -12V rail should be within +-5% ie. acceptable voltage range of rail is (11.4V, 12.6V) both for positive and negative
- - +-12V rail shall be capable of providing no more than 5mA of current
- - There is a 3V3 powered uC on board with available PWM output which could be used for charge pumps
- Everything mentioned so far asks for a charge pump, the way how I see it.
- Some options I found:
- Maxim/Analog have +5V to +-10V converter IC [MAX680/681](https://pdfserv.maximintegrated.com/en/ds/MAX680-MAX681.pdf), with VCC max of 6.2V and V+/V- being +12V/-12V in absolute maximum ratings, I feel like stretching it- - Do a DIY charge pump using PWM uC output - haven't done this earlier so if someone could explain a concept with jellybean components that would be a useful answer as well.
- - Use a standalone 5V to +-12V converter like a [Murata one](https://eu.mouser.com/datasheet/2/281/1/kdc_nmv-2941136.pdf)
- - Use 2x dedicated charge pumps - 5V to 12V and 12V to -12V([TC1044S](https://ww1.microchip.com/downloads/en/DeviceDoc/21348a.pdf))
- Questions:
- - Could charge pump 5V to +-12V be implemented with 1xPWM output from the uC, how would the circuit look like and what would be the component values(capacitor size, diodes, etc.)?
- - Are there some other way how to do this which I have not covered?
- I would like to convert 5V rail I have on PCB to +-12V. Existing solution is using boost converter 5V to 12V, and a buck for 5V to -12V. This feels bulky for what it's needed - here are the requirements:
- - +12V and -12V rail shall serve for powering opamp only
- - Ripple of the +-12V rail is not of a concern, as the opamp is used in comparator mode(something I would like to swap with the comparator in the future but keeping it for now in the design)
- - +12V and -12V rail should be within +-5% ie. acceptable voltage range of rail is (11.4V, 12.6V) both for positive and negative
- - +-12V rail shall be capable of providing no more than 5mA of current
- - There is a 3V3 powered uC on board with available PWM output which could be used for charge pumps
- Everything mentioned so far asks for a charge pump, the way how I see it.
- Some options I found:
- - Maxim/Analog have +5V to +-10V converter IC [MAX680/681](https://pdfserv.maximintegrated.com/en/ds/MAX680-MAX681.pdf), with VCC max of 6.2V and V+/V- being +12V/-12V in absolute maximum ratings, I feel like stretching it + it is not within acceptable voltage range
- - Do a DIY charge pump using PWM uC output - haven't done this earlier so if someone could explain a concept with jellybean components that would be a useful answer as well.
- - Use a standalone 5V to +-12V converter like a [Murata one](https://eu.mouser.com/datasheet/2/281/1/kdc_nmv-2941136.pdf)
- - Use 2x dedicated charge pumps - 5V to 12V and 12V to -12V([TC1044S](https://ww1.microchip.com/downloads/en/DeviceDoc/21348a.pdf))
- Questions:
- - Could charge pump 5V to +-12V be implemented with 1xPWM output from the uC, how would the circuit look like and what would be the component values(capacitor size, diodes, etc.)?
- - Are there some other way how to do this which I have not covered?
#1: Initial revision
Converting 5V to +/-12V
I would like to convert 5V rail I have on PCB to +-12V. Existing solution is using boost converter 5V to 12V, and a buck for 5V to -12V. This feels bulky for what it's needed - here are the requirements: - +12V and -12V rail shall serve for powering opamp only - Ripple of the +-12V rail is not of a concern, as the opamp is used in comparator mode(something I would like to swap with the comparator in the future but keeping it for now in the design) - +12V and -12V rail should be within +-5% ie. acceptable voltage range of rail is (11.4V, 12.6V) both for positive and negative - +-12V rail shall be capable of providing no more than 5mA of current - There is a 3V3 powered uC on board with available PWM output which could be used for charge pumps Everything mentioned so far asks for a charge pump, the way how I see it. Some options I found: - Maxim/Analog have +5V to +-10V converter IC [MAX680/681](https://pdfserv.maximintegrated.com/en/ds/MAX680-MAX681.pdf), with VCC max of 6.2V and V+/V- being +12V/-12V in absolute maximum ratings, I feel like stretching it - Do a DIY charge pump using PWM uC output - haven't done this earlier so if someone could explain a concept with jellybean components that would be a useful answer as well. - Use a standalone 5V to +-12V converter like a [Murata one](https://eu.mouser.com/datasheet/2/281/1/kdc_nmv-2941136.pdf) - Use 2x dedicated charge pumps - 5V to 12V and 12V to -12V([TC1044S](https://ww1.microchip.com/downloads/en/DeviceDoc/21348a.pdf)) Questions: - Could charge pump 5V to +-12V be implemented with 1xPWM output from the uC, how would the circuit look like and what would be the component values(capacitor size, diodes, etc.)? - Are there some other way how to do this which I have not covered?