Optimizing astable multivibrator for minimum power consumption

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Discussion Overview

The discussion revolves around optimizing an astable multivibrator circuit for minimum power consumption, focusing on component selection such as capacitors and resistors, and exploring alternative configurations using operational amplifiers.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant inquires about the optimum values for capacitors and resistors in a BJT-based multivibrator to achieve a specific frequency.
  • Another participant suggests using an operational amplifier (LMC6041) instead of transistors, referencing a specific circuit from the data sheet.
  • A different participant expresses a desire to understand the multivibrator's operation in terms of basic components like transistors, resistors, capacitors, and diodes.
  • One participant, acknowledging their lack of expertise, proposes using low power transistors, possibly FET or JFET types, and emphasizes minimizing capacitance, operating voltage, and maximizing resistance to reduce power consumption. They note that actual component values will depend on various factors including transistor type and load impedance.
  • A link to the Von Neumann-Landauer limit is provided, possibly to contextualize the discussion within theoretical limits of energy consumption.

Areas of Agreement / Disagreement

Participants present multiple competing views regarding the choice of components and configurations for the multivibrator, indicating that the discussion remains unresolved with no consensus on the optimal approach.

Contextual Notes

Participants mention various factors that could influence the choice of components, such as the type of transistors used, wave shape requirements, and load impedance, which may not have been fully explored or defined in the discussion.

aeftimia
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In short, if I want a given frequency, and I use BJT transistors, what would be the optimum capacitors and resistors in a multivibrator.

Example:
http://upload.wikimedia.org/wikipedi...tivibrator.svg

So, what are the optimum values C1=C2, R1=R4, and R2=R3?
 
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Don't use transistors.
Use operational amplifier Nation Semiconductor type LMC6041.
Use circuit figure 11 from LMC6041 data sheet.
 
I know the best way to go is to get the thing built on a chip. I was trying to understand how the chip works in terms of components I understand--i.e. transistors, resistors, capacitors, and diodes.
 
This is not my area of expertise, so someone correct me if I'm wrong.
Use the lowest power transistors available. ? Probably FET or JFet transistors?
The energy stored in the capacitors each cycle is wasted, so use the lowest possible capacitance.
Use the lowest possible operating voltage.
Use the highest resistance resistors possible.
The actual value of the resistors and capacitors will depend on the transistors that are used, the wave shape requirements and the load impedance.
 

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