Hi all;
I just made an amplifier with two LM3886 in parallel configuration
with servo circuit.But i have some thermal problems.Circuit draws 200 mA quiescent current from each rail.With the +/- 33 V of supply voltage idle thermal dissipation exceeds 13 Watts.I think that it's not a normal.Anybody encountered this problem before?
Waiting your comments.
I just made an amplifier with two LM3886 in parallel configuration
with servo circuit.But i have some thermal problems.Circuit draws 200 mA quiescent current from each rail.With the +/- 33 V of supply voltage idle thermal dissipation exceeds 13 Watts.I think that it's not a normal.Anybody encountered this problem before?
Waiting your comments.
Hi Nitro
The max. idle currnet for ONE LM3886 is 80 mA (and I have never really seen it this high) so for two it should max. be 160 mA + additional circuits.
Either you have to much DC-offset (if your DCServo is working OK you should not have this problem.) or you have osc.
Having worked with 4 x LM3886 in bridged/paralle configuration I typicall ended up with around 250 mA idle current so your 200 mA for just two LM3886 seems "wrong".
Have fun
Thomas
The max. idle currnet for ONE LM3886 is 80 mA (and I have never really seen it this high) so for two it should max. be 160 mA + additional circuits.
Either you have to much DC-offset (if your DCServo is working OK you should not have this problem.) or you have osc.
Having worked with 4 x LM3886 in bridged/paralle configuration I typicall ended up with around 250 mA idle current so your 200 mA for just two LM3886 seems "wrong".
Have fun
Thomas
Hi Thomas
I'm still making modifications on the circuit from yesterday, and finally got 150mA at idle.I think that it is a good value for two ics.Maybe i can lower this current 100-200 mA less, stil trying.Actually not a high value for home use but im gonna use this at car so the dissipation must be low.
Thanks for all replies.
Türker
I'm still making modifications on the circuit from yesterday, and finally got 150mA at idle.I think that it is a good value for two ics.Maybe i can lower this current 100-200 mA less, stil trying.Actually not a high value for home use but im gonna use this at car so the dissipation must be low.
Thanks for all replies.
Türker
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