VU LED - looking for drivers

[Steinberg]

Hello, I'm looking for some good driver to build led vu meter...

I know there is LM3915, but I'm looking for something else.
I wanna build led meter for eng mixer, I dream about meter like
at Sound Devices 302 (of corse without setup function).
-30/-20dB to +20dB.
I want to turn only point as indicator & need to fade in/out of
light for power saving.

Any solutions? please help

 

[sofaspud]

The LM3915 is really just a specialized comparator circuit fabricated on a single die. You could do the same (and more) using comparator ICs. Your reference and resolution would determine the final schematic.
I'm not aware of a specific LM3915 "upgrade" chip, but that doesn't mean there are none. You could have a look at TI, NXP, ON semiconductor makers' websites to see what is available.

 

[ticknpop]

Try the early Dorrough A40 - it used LM3915 for driver - very nice peak/rms meter
There are always some on ebay -

 

[AuroraB]

Velleman had some kits that were using UAA or ULN devices...don't recall exactly which... some googling should find them......

I built a couple of meters for a community radio project back in the 80s, using two cascaded LM3915s in spot mode. Worked quite well..... drawings should be avalable on the net......

 

[Steinberg]

Maybe really I should go for LM3915...
I have to find right drawings.

thx Guys

 

[mickeymoose]

Check this site: VU metr :: S-O

 

[Enzo]

Or find a dead stereo receiver and steal teh VU meter circuitry from it.

 

[dangus]

Rohm had some chips like the BA681A which drove 12 LEDs.

Siemens made the UAA180 which also drove 12 LEDS. Google images for UAA180 will turn up umpteen schematics and even board layouts. Presumably searching on LM3915 will also turn up some useful images.

 

[gmphadte]

On the datasheet of LM3915, u will find peak and average detector circuits.

Gajanan Phadte

 

[audiofan]

You should read LM 3916 & LM3915 data sheet and application notes ..... lot of stuff there .

 

[Steinberg]

VU metr :: S-O RULEZ


I'm looking for VU meter style like this.
LM3915/16 drives leds like crazy; I think it's quite more toy than tool.
I know how works dB scale, but I just don't like 3915/16.

 

[dangus]

Well, it looks like all the info is there. Hex code, board layout, so why not build one? If you want more features, like simultaneous peak and average display, a microcontroller can do that with a much lower parts count than analog chips.

Here's one with 40 LEDs, but not very cheap. http://www.jlmaudio.com/shop/index.php?_a=viewProd&productId=100

American Audio makes a rack mount 2-channel wide range level meter ("dB display") that sells on eBay for under $60.