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This is how I tried to connect a BT-M512RD-DR1 LED panel, but it doesn't really work. This is the datasheet. Basically I have just used 2 wires of the 10 k\$\Omega\$ potentiometer. There is no change in brightness.

enter image description here

So again, the question is - what is the proper way to connect the brightness control pot to the LED display?

zebonaut
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Pablo
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    Datasheet gives you an application circuit on how to connect the brightness pot. Look at page3 block diagram. Also look at page 4 where they describe how to control the brightness. – Chetan Bhargava Jan 22 '13 at 21:56

3 Answers3

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Read the datasheet more carefully.

enter image description here

enter image description here

Phil Frost
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  • Same here - I'm too slow on the draw. – HikeOnPast Jan 22 '13 at 22:01
  • Is that a capacitor connected between ground and brt control pin? If yes, what should be the value? – Pablo Jan 22 '13 at 22:09
  • @Pablo looks like it. I suspect it's to eliminate any noise on the brightness. I'd use whatever value of decoupling capacitor you have handy by the bucketful, like 100nF. – Phil Frost Jan 22 '13 at 22:12
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The datasheet describes the function of brightness control as such.

enter image description here

It specifies a maximum current of 550uA into this pin.

The datasheet describes an 18-pin device; you show an 8 pin device. In the datasheet, the brightness control pin is pin 18, while you're using pin 3.

HikeOnPast
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From your schematic it is a bit hard to tell what is what. But just to double check, you have the display connected like this, correct?

7 seg display connection

So it looks like the pin 18 of the display need to be connected between the variable resistor and ground.

Garrett Fogerlie
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