"Signal Lock" Indicator for CS8412/TDA1543

[Nisbeth]

Hi There!


I've build Fedde's NONOZ-II DAC using the CS8412/TDA1543-combination and my own PCB-layout. Is there a way to put a "signal-lock"-LED on the CS8412 so I can see if a signal is present on the input of the receiver?


/U.

 

[scottnixon]

Lock LED

Pin 28 of the 8412 goes 'low' with valid signal lock, if that's what you need to know.

 

[rfbrw]

Pin 25, the ERF flag goes high when out of lock. I use a red led to gnd so that it goes out when the signal is locked. Connecting an led between V+ and pin 25 will do the opposite.

 

[Nisbeth]

Re: Lock LED

Pin 28 of the 8412 goes 'low' with valid signal lock, if that's what you need to know.

So an LED + a resistor from pin 28 to V+ will give me the indicator I want, right?



/U.

 

[peranders]

Hi There!


I've build Fedde's NONOZ-II DAC using the CS8412/TDA1543-combination and my own PCB-layout. Is there a way to put a "signal-lock"-LED on the CS8412 so I can see if a signal is present on the input of the receiver?
/U.

You can see how I have done. Note also that I take out the frequency information with a flip-flop.

http://home.swipnet.se/~w-50719/hifi/dac/dac_schema_sida_1.html

 

[rfbrw]

Pin 25 not 28. See the datasheet. http://www.geocities.com/rjm003.geo/rjmaudio/pdf/cs8411.pdf

 

[scottnixon]

28 is fine

Nisbeth, I think you've got it... If you hard tie the anode to a +5, a 200 - 1000 ohm ought to do fine, depending on the LED. You can do the reverse with pin 25, BUT I'd rather 'ground' an LED to fire it as opposed to actually using the chips internals to drive it high. That's just me

 

[Nisbeth]

Thanks Scott, I'll try it


/U.