LEDs Light Up At Power On (Uggh!!)

Other Hardware LEDs and Multiplexing
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The circuit consists of 8 red LEDs connected to a 74HC595 Shift Register, which is driven by an Uno R3. (schematic attached) The LEDs light up based on the amplitude of audio samples and both the hardware and Arduino code are working great. The issue is a minor thing I know, but it bothers me none the less.

The issue: When power is applied the LEDs light bright before the program starts running.

When I apply power, I don't want any lights on until the program "says its time". My initial circuit had the shift register Output Enable pin (low active) tied to ground. So I figured if I tied the OE pin to a Uno digital output pin then all would be good (or should I say dark). But no such luck.

So, how can I prevent the shift register outputs from being high at power on? There must be a hardware "trick" that I could use but I sure don't know what it is.

Thank you in advance,
Dennis

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Put a 10k pull-up - that is to +5 V - on your ~OE pin.

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Put a 10k pull-up - that is to +5 V - on your ~OE pin.

Well thank you. I will do that and report back.

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I added the 10K pull-up and IT WORKS!! Thank you soo much Paul.

I can't tell you how much that bothered me, I know it sounds silly but everything else in the project is working great. The LEDs turning on at the start of each demo spoiled the surprise because they are mounted in the base of vacuum tube sockets and the glass tubes light up based on the audio level. I didn't want the tubes to light until the music started, which is how it works now.

Thanks again, I owe you a beer.
Dennis

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