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Low cost/Low performance op-amp with an enable pin

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guitargore

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Need to find a dual op-amp with an enable pin to drive the input of a push-pull driver stage. Don't need high speed, don't need high accuracy, just need low cost i.e. <$0.25/10k. Any suggestions?
 

Some time back I had same problem. I ended up with making a external circuit counting 4 bjt's to get this function.

One backdraw with this solution is that mostly bjt datasheets doesn't specify Vbc, so can't be sure if Q1 and Q2 can withstand 12V.
 

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I am also playing with the idea of gating the input to the the circuit using a CE amplifier with a PNP load that I can switch. Very crude but almost no cost other than the area, which isn't a big deal at this time.
 

One backdraw with this solution is that mostly bjt datasheets doesn't specify Vbc, so can't be sure if Q1 and Q2 can withstand 12V.
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??? Maximum Vbc reverse voltage is specified in datasheets and >= maximum Vce. Reverse Vbe is however limited to e.g. 6 V. If the amplifier output is externally loaded, the safe supply voltage isn't larger than 6V respectively 12 V for truely floating output.
 

Ncs2002 / ncv2002
 

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