Comments: Dot/Bar Display Driver Hookup Guide
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Hi. Please can you post the schematic of the 4 (or more) daisy chained LM3914? Thanks...
I'm having problems with this equation and these numbers from the tutorial.
"VREF = 1.25V(1+R2/R1)+R2x80uA In the circuit above, where R1 is 2.2kΩ and R2 is 3.3kΩ, VREF will be about 3.4V (safely 1.5V under the supply voltage)."
3.4 != 1.25x(1+3.3/2.2)+3.3x0.8 Where am I making a mistake?
Hi, thank you for the great post, it helped me a lot to incorporate a battery indicator into an expositing project. Could you maybe please just help me with the resistor values when using a 4.2V lipo battery instead?
Hey there, it looks like you are looking for some technical assistance. Please post a new topic on our forums for assistance from our technical support team. They will do their best to assist you.
Otherwise, I believe the information you are looking for is covered in the IC Overview and Setting the Reference Voltage and LED Current sections of this guide. (*Not explicitly, but the information should help you figure it out.)
I am struggling with the function R(adj). Why is it sometimes tied to ground and other it has a voltage divider? Also in the cascading example it seems that the R(hi) is tied to ground on the bottom chip, and it sends its R(Lo) to the other chip.
How were you able to connect the bar graphs to the power rail and keep them next to each other? When I try it there is a gap between them.
Heh, yeah...darn that gap. I ended up bending the legs that hit the gap 90° over, and wrapping them around the next leg over (for a temporary solution, soldering for more permanent).