Mark A Winters wrote:
>
> Hello All,
>
> Hopefully someone on this list has some experience with the ISD audio recordin
g/playback chips. If so, has anyone been successful recording to
one of these chi
>
> The circuit example that come with the datasheet for the 1400 series shows a m
icrophone input, though it also says that "...if the desired
input is derived fro
>
> Following this advice, I've hooked up the negative headphone output from the s
tereo to the circuit ground, and have the positive signal going
through a .1uF ca
>
> Does anyone see anything wrong with this setup? BTW, since I'm not using a mic
rophone for input, I don't have anything connected to the MIC,
MIC REF, or ANA OU
>
> Any advice (or a pointer to a working circuit diagram) would be greatly apprec
iated!
>
> Thanks,
> Mark
>
>     ---------------------------------------------------------------
> Hello All,
>
> Hopefully someone on this list has some experience with the ISD audio
> recording/playback chips. If so, has anyone been successful recording
> to one of these chips directly using the headphone output from a
> stereo or computer, rather than using a microphone as input?
>
> The circuit example that come with the datasheet for the 1400 series
> shows a microphone input, though it also says that "...if the desired
> input is derived from a source other than a microphone, the signal can
> be fed, capacitively coupled, into the ANA IN pin directly."
>
> Following this advice, I've hooked up the negative headphone output
> from the stereo to the circuit ground, and have the positive signal
> going through a .1uF capacitor and 100K pot (in series) to the ANA IN
> pin on the 1400. When I attempt to record to the chip, I hear a loud
> "hum" coming from the speaker. When I try to play it back, I don't
> hear any audio, other than a "click" when it reaches the EOM marker.
>
> Does anyone see anything wrong with this setup? BTW, since I'm not
> using a microphone for input, I don't have anything connected to the
> MIC, MIC REF, or ANA OUT pins, nor do I have anything connected to the
> ~RECLED pin other than a resistor and LED. (The application diagram
> shows this pin also connected to the microphone components). I do have
> the AGC pin connected to a resitor and capacitor as shown in the
> diagram.
>
> Any advice (or a pointer to a working circuit diagram) would be
> greatly appreciated!
>
> Thanks,
> Mark

May i help you? I have recording from a Sound Blaster output source!

I'm was using the ISD1420, now i use the ISD33...

Miguel.