Hi Michael,
I am having some difficulty in trying to wire up the circuit.The smoke Det chip that is in the smoke alarm unit is called A5348CA.The web site for data sheets is as follows
http://212.57.231.17/datasheets/18/OSNNSVOWQQ.pdf
Pin 15 is soldered directly to the piezo element.Can you tell me what pin out1 and out2 were in your diagram in relation to the datasheet A5348CA.
Thank you,
Tina