http://html.alldatasheet.com/html-pdf/145873/YOUDA/YD2030/459/3/YD2030.html
http://html.alldatasheet.com/html-pdf/25043/STMICROELECTRONICS/TDA2030/3247/2/TDA2030.html
сигнализатор, зујалки, звонче, мини-радио приемник..... за све што имаш идеа...