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Ozen
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- TL;DR Summary
- How can you increase the battery life of a circuit with a specific minimum LED mA?
Hello Everybody!
I am new to electrical engineering and only had 1 formal intro class on the subject (albeit I did very well in it) and have found myself in a position where I need to design a circuit for a micro reflex sight I have been designing. So let me first describe how my competitors battery information I could dig up: they use a CR2032 which has a current flow of .2mA, capacity of 220mAh, and voltage of 3.0V. They claim on their highest setting the battery lasts for ~25 days (~600 hours), which I plugged this data into a battery life calculator and that yields their current for that as ~.36mA. My understanding of this part is the battery only runs optimally at the specified .2mA but the circuit can demand more current or less current than that. On their #4 setting they claim the battery can last 4 years (~35000 hours), which would be around .0063mA on continual usage. How the on Earth do they achieve that?
Looking at how my circuit is coming along, it will be a battery, likely the CR2032, which leads to a push button to toggle power on/off, then going to a voltage regulator (maybe a capacitor too to even the flow out) into a micro-controller with 2 push buttons in the loop to control the brightness levels, out to the LED with maybe a resistor in front of it, and that completes it. Looking at the micro LED chips, the only suitable chip I could find was the L128-DRD1003500000 which has a Vf of 2.15V and If of 120mA. Which seems like it is quite power hungry. So I expanded out into looking at just the bare dies and having them integrated into a circuit board itself, but I can't find any under 20mA with a suitable emission area. Which brings up another point, let's take the LA-HR20WP3 bare die as example (here is the link: https://www.chips4light.com/assets/files/products/LA-HR20WP3.pdf): notice the N contact in the middle of the emission area? Isn't that interrupting the light path and not going to form the light image I want, even with the usage of a mask? Or does it somehow not effect it? I head about solid state LED's but can't find any that aren't power hungry green wavelength ones.
So with all that said, I have no clue how to get this battery life anywhere near what my competitors have. The brightness is controlled by a PWM so it will be hitting that current rate very briefly, and then the micro-controller will be continually using current, along with the voltage regulator, so it doesn't seem possible to get consumption so low it is around the .0063mA region. And to top it off, say I use one of the bare dies I have found, isn't it going to be insanely expensive to have a PCB made with a bare die integrated to it, especially when trying to get a prototype made?
Any insight you can offer to this newbie in this field struggling with getting things rolling is much appreciated!
I am new to electrical engineering and only had 1 formal intro class on the subject (albeit I did very well in it) and have found myself in a position where I need to design a circuit for a micro reflex sight I have been designing. So let me first describe how my competitors battery information I could dig up: they use a CR2032 which has a current flow of .2mA, capacity of 220mAh, and voltage of 3.0V. They claim on their highest setting the battery lasts for ~25 days (~600 hours), which I plugged this data into a battery life calculator and that yields their current for that as ~.36mA. My understanding of this part is the battery only runs optimally at the specified .2mA but the circuit can demand more current or less current than that. On their #4 setting they claim the battery can last 4 years (~35000 hours), which would be around .0063mA on continual usage. How the on Earth do they achieve that?
Looking at how my circuit is coming along, it will be a battery, likely the CR2032, which leads to a push button to toggle power on/off, then going to a voltage regulator (maybe a capacitor too to even the flow out) into a micro-controller with 2 push buttons in the loop to control the brightness levels, out to the LED with maybe a resistor in front of it, and that completes it. Looking at the micro LED chips, the only suitable chip I could find was the L128-DRD1003500000 which has a Vf of 2.15V and If of 120mA. Which seems like it is quite power hungry. So I expanded out into looking at just the bare dies and having them integrated into a circuit board itself, but I can't find any under 20mA with a suitable emission area. Which brings up another point, let's take the LA-HR20WP3 bare die as example (here is the link: https://www.chips4light.com/assets/files/products/LA-HR20WP3.pdf): notice the N contact in the middle of the emission area? Isn't that interrupting the light path and not going to form the light image I want, even with the usage of a mask? Or does it somehow not effect it? I head about solid state LED's but can't find any that aren't power hungry green wavelength ones.
So with all that said, I have no clue how to get this battery life anywhere near what my competitors have. The brightness is controlled by a PWM so it will be hitting that current rate very briefly, and then the micro-controller will be continually using current, along with the voltage regulator, so it doesn't seem possible to get consumption so low it is around the .0063mA region. And to top it off, say I use one of the bare dies I have found, isn't it going to be insanely expensive to have a PCB made with a bare die integrated to it, especially when trying to get a prototype made?
Any insight you can offer to this newbie in this field struggling with getting things rolling is much appreciated!