MC14568

www.DataSheet4U.com Freescale Semiconductor Product Preview Document Number: MC14568 Rev. 1.0, 11/2006 Low-Power CMOS Ionization Smoke Detector with Interconnect and Timer The MC14568, when used with an ionization chamber and a small number of external components, will detect smoke. When smoke is sensed, an alarm is sounded via an external piezoelectric transducer and internal drivers. This circuit is designed to operate in smoke detector systems that comply with UL217 and UL268 specifications. An internal oscillator with associated logic controls the overall functionality by powering down the device for 1.67 seconds and sensing smoke in a 10 ms window. In this way, standby current consumption is reduced to between 5.0 and 9.0 µA, thus providing longer battery life. In addition, a networking capability allows as many as 125 to be interconnected so that if any unit senses smoke, all units will sound an alarm. The MC14568 is supplied in a 16-pin dual in-line plastic package and is designed to run on a power supply between 6 to 12 Volts. Features Speed-Up Sampling Rate of 40 ms of Internal Clock Period (Pin 12) After First Detection of Smoke Timer Function for Reduced Sensitivity for a Nominal Period of 6.43 Minutes (10 Minutes Max) High-Smoke Detection in the “Reduced Sensitivity” Mode Internal and External Low Battery Threshold Internal and External Smoke Reference Settings Guaranteed Power Up Without Random LED and Horn Chirps Reversed Battery Protectio...