Photoelectric Smoke Detectors Source: Microchip
Introduction Purpose An   Overview   on   Microchip’s   Smoke   Sensor:   RE46C14X Outline Horn   Driver   Roadmap,   Photoelectric   Smoke   Detector   Products Features   of   RE46C14X Functional   Block   Diagram   and   Typical   Application   using   RE46C14X Content 13   pages
Sensor Trends Sensor proliferation into general consumer products Automotive: Environment control, TPMS Fitness: Portable heart rate monitoring, body fat & weight scales, sneaker sensors High accuracy measurement Industrial: Chemical processing, high-tech material production Pharmaceutical/Medical: drug synthesis, biometrics
Sensing Application Requirements Sufficient Accuracy There exists industrial and medical applications increasing looking for better accuracy  Low Power Longer battery life Smaller form factor Particularly driven by portable consumer gadgets Thermocouple MEMS Load Cell
Horn Driver Roadmap
Photoelectric Smoke Detector Products Photoelectric Smoke ASICs RE46C140  Hush Timer, Interconnect, Temporal Horn Pattern RE46C141  Interconnect, Temporal Tone Horn Pattern RE46C143  Interconnect, Continuous Horn Pattern RE46C144  Hush Timer, Interconnect, Continuous Tone Horn Pattern RE46C145  Hush Timer, Interconnect, Temporal Horn Pattern, Alternate Diagnostic Mode (for calibration)
How Do Photoelectric Smoke  Detector Driver Work?
Photoelectric Smoke Detector Products
Features   of   RE46C14X   Internal Power On Reset  Low Quiescent Current Consumption  Available in 16L PDIP, 16L N SOIC or 16L W SOIC  ESD Protection on all Pins  Interconnect up to 40 Detectors  10 Minute Timer for Sensitivity Control  Temporal Horn Pattern  Internal Low Battery and Chamber Test  Compatible with Allegro A5366  UL Recognized per File S24036  Available in Standard Packaging or RoHS Compliant Pb Free Packaging.
Functional Block Diagram
Typical Application
Ionization Smoke Detectors vs.  Photoelectric Smoke Detectors Ionization < Cost Ionization contains hazardous material Photoelectric is better at Smoldering type fire detection (particles) Ionization is better for gas type fires Ionization is a lower current application, samples for smoke more often than Photoelectric Europe prefers Photoelectric America’s Prefer Ionization Asia mixed with China & Japan preferring Photo. All R&E Products are developed for products that meet UL217 and UL268
Additional Resource For ordering RE46C14X devices, please click the part list or Call our sales hotline For more product information go to http://www.microchip.com/ParamChartSearch/chart.aspx?branchID=9032&mid=11&lang=en&pageId=79 Visit element14 to post your question   www.element-14.com For additional inquires contact our technical service hotline or even use our “Live Technical Chat” online facility Newark Farnell

Photoelectric Smoke Detectors

  • 1.
  • 2.
    Introduction Purpose An Overview on Microchip’s Smoke Sensor: RE46C14X Outline Horn Driver Roadmap, Photoelectric Smoke Detector Products Features of RE46C14X Functional Block Diagram and Typical Application using RE46C14X Content 13 pages
  • 3.
    Sensor Trends Sensorproliferation into general consumer products Automotive: Environment control, TPMS Fitness: Portable heart rate monitoring, body fat & weight scales, sneaker sensors High accuracy measurement Industrial: Chemical processing, high-tech material production Pharmaceutical/Medical: drug synthesis, biometrics
  • 4.
    Sensing Application RequirementsSufficient Accuracy There exists industrial and medical applications increasing looking for better accuracy Low Power Longer battery life Smaller form factor Particularly driven by portable consumer gadgets Thermocouple MEMS Load Cell
  • 5.
  • 6.
    Photoelectric Smoke DetectorProducts Photoelectric Smoke ASICs RE46C140 Hush Timer, Interconnect, Temporal Horn Pattern RE46C141 Interconnect, Temporal Tone Horn Pattern RE46C143 Interconnect, Continuous Horn Pattern RE46C144 Hush Timer, Interconnect, Continuous Tone Horn Pattern RE46C145 Hush Timer, Interconnect, Temporal Horn Pattern, Alternate Diagnostic Mode (for calibration)
  • 7.
    How Do PhotoelectricSmoke Detector Driver Work?
  • 8.
  • 9.
    Features of RE46C14X Internal Power On Reset Low Quiescent Current Consumption Available in 16L PDIP, 16L N SOIC or 16L W SOIC ESD Protection on all Pins Interconnect up to 40 Detectors 10 Minute Timer for Sensitivity Control Temporal Horn Pattern Internal Low Battery and Chamber Test Compatible with Allegro A5366 UL Recognized per File S24036 Available in Standard Packaging or RoHS Compliant Pb Free Packaging.
  • 10.
  • 11.
  • 12.
    Ionization Smoke Detectorsvs. Photoelectric Smoke Detectors Ionization < Cost Ionization contains hazardous material Photoelectric is better at Smoldering type fire detection (particles) Ionization is better for gas type fires Ionization is a lower current application, samples for smoke more often than Photoelectric Europe prefers Photoelectric America’s Prefer Ionization Asia mixed with China & Japan preferring Photo. All R&E Products are developed for products that meet UL217 and UL268
  • 13.
    Additional Resource Forordering RE46C14X devices, please click the part list or Call our sales hotline For more product information go to http://www.microchip.com/ParamChartSearch/chart.aspx?branchID=9032&mid=11&lang=en&pageId=79 Visit element14 to post your question www.element-14.com For additional inquires contact our technical service hotline or even use our “Live Technical Chat” online facility Newark Farnell

Editor's Notes

  • #2 Photoelectric Smoke Detectors
  • #3 Welcome to the training module on Microchip’s Photoelectric Smoke Detectors.
  • #4 Sensors are appearing in more and more general consumer products. Many other industries also widely use sensors within applications, some of which require high accuracy and reliability. A few examples are within chemical processing, high-tech material production, pharmaceuticals, just to name a few. Accuracy is critical within these applications to ensure high yields and an overall quality production process
  • #5 As just stated, industrial applications such as chemical processing, pharmaceuticals, and industrial production require tight temperature control and highly accurate ingredient mixing. Consumer products and more portable type products such as hand held products, gaming controls (Nintendo Wii™) and wireless systems are driving the need for low power and smaller sized solutions. These requirements relate to the cost, reliability and performance of sensing solutions within their end product. All of which are critical considerations during a design and new product development cycle. In most situations designers and new product teams deal with tradeoffs between typical application requirements. Microchip offers many different alternatives within the signal chain which gives designers the flexibility to make the right tradeoff decision.
  • #6 This page shows Horn Driver Road MAP which are Piezoelectric based on, baseline ASIC Products: it includes RE46C100 basic model, Vdd 6V - 16V, RE46C101 with LED Driver, Vdd 6V - 16V, RE46C104 with Voltage Converter, Vdd 4V-8V, RE46C117 with Charge Pump, Vdd 2V - 5V
  • #7 This page gives information about smoke detector products it includes RE46C140, RE46C141, RE46C143, RE46C144, RE46C145.
  • #8 Infrared LED is used as a light source and A light chamber is used to detect “reflected light” Light is scattered by smoke particles and the scattered light is detected using photo detector. High Gain Amplifier used to amplify low signal, High Current Drive for LED bias
  • #9 This page gives smoke detector product portfolio which includes RE46140, 141, 145, 143, 144 products. Temporal horn pattern is in compliance with the National Fire Protection Association (NFPA) regulations.
  • #10 The RE46C140 is low power CMOS photoelectric type smoke detector IC. With minimal external components this circuit will provide all the required features for a photoelectric type smoke detector.
  • #11 This page shows functional block diagram of smoke sensor, it has gain selectable photo amplifier for use with an infrared emitter/detector pair. An internal oscillator strobes power to the smoke detection circuitry for 100us every 10 seconds to keep standby current to a minimum. If smoke is sensed the detection rate is increased to verify an alarm condition. A check for a low battery condition and chamber integrity is performed every 43 seconds when in standby. The temporal horn pattern supports the NFPA 72 emergency evacuation signal. An interconnect pin allows multiple detectors to be connected such that when one units alarms, all units will sound. An internal 10 minute timer can be used for a reduced sensitivity mode.
  • #12 This page shows typical application circuit using smoke sensor device RE46C14X. The internal oscillator has a nominal period of 10mS. Normally the analog circuitry is powered down to minimize standby current (typically 4uA at 9V). Once every 10 seconds the detection circuitry (normal gain) is powered up for 10 ms. Prior to completion of the 10mS period the IRED pulse is active for 100 us. Three consecutive smoke detections will cause the device to go into alarm and the horn circuit and interconnect will be active. Once every 40 seconds, the status of the battery voltage is checked. This status is checked and latched at the conclusion of the LED pulse.
  • #13 This page gives differences of Ionization Smoke Detectors vs. Photoelectric Smoke Detectors.
  • #14 Thank you for taking the time to view this presentation on “ RE46C14X” . If you would like to learn more or go on to purchase some of these devices, you may either click on the part list link right beside the play button on the TechCast portal, or simply call our sales hotline. For more technical information you may either visit the Microchip site, or if you would prefer to speak to someone live, please call our hotline number, or even use our ‘live chat’ online facility. You may visit Element 14 e-community to post your questions.