RE46C165SW16F Microchip

RE46C165/6/7/8 CMOS Photoelectric Smoke Detector ASIC with Interconnect, Timer Mode and Alarm Memory Features Description Temporal Horn Pattern or Continuous Tone The RE46C165/6/7/8 devices are low-power, CMOS photoelectric type, smoke detector ICs. With minimal Alarm Memory external components, these circuits will provide all the Sensitivity Control Times: required features for a photoelectric type smoke - 9 minutes (RE46C165/6) detector. - 1.2 minutes (RE46C167/8) Each design incorporates a gain selectable photo I/O Filter and Charge Dump amplifier for use with an infrared emitter/detector pair. Interconnect up to 40 Detectors An internal oscillator strobes power to the smoke Internal Power-on Reset detection circuitry for 100 s every 10 seconds to keep >2000V ESD Protection (HBM) on All Pins standby current to a minimum. If smoke is sensed, the Low Quiescent Current Consumption (<8 A) detection rate is increased to verify an alarm condition. A high gain mode is available for push button chamber Internal Low Battery Detection and Chamber Test testing. RoHS Compliant Lead-Free Packaging A check for a low battery condition and chamber integrity is performed every 43seconds when in standby. The temporal horn pattern supports the NFPA 72 emergency evacuation signal. An interconnect pin allows multiple detectors to be connected so when one unit alarms, all units will sound. A charge dump feature will quickly discharge the interconnect line when exiting a local alarm. The interconnect input is also digitally filtered. An internal timer allows for single button, push-to-test to be used for a reduced sensitivity mode. An alarm memory feature allows the user to determine if the unit has previously entered a local alarm condition. Utilizing low-power CMOS technology, the RE46C165/6/7/8 was designed for use in smoke detectors that comply with Underwriters Laboratory Specification UL217 and UL268. 2010 Microchip Technology Inc. DS22251A-page 1RE46C165/6/7/8 Package Types RE46C165/6/7/8 PDIP, SOIC C1 1 16 TEST C2 2 15 VSEN DETECT 3 14 V SS STROBE ROSC 4 13 V 5 12 COSC DD 6 11 IRED LED IO 7 10 FEED HORNB 8 9 HORNS Functional Block Diagram V (5 ) DD R1 IO (7) + 276K FEED (10) - R2 HS (9) 124K V (14) + SS - Logic and VSEN (15) HB (8) Timing LED (11) V 3.5V DD V 5V Reference DD STROBE (4) Photoamp Bias and DETECT (3) + Power - Reset IRED (6) C1 (1) C2 (2) ROSC (13) TEST (16) Oscillator COSC (12) DS22251A-page 2 2010 Microchip Technology Inc.