3V Photo Smoke Detector IC With Programmable Setup, Calibration and Operating Modes Dec 2010 Hello, and welcome to the Microchip Technology Webinar overview of the RE46C190 Three Volt Photo Smoke Detector IC. This Webinar will present the features and functions of this new low voltage programmable smoke detector IC. 1
Key Features Operating Voltage from 2V to 5.5V Low Quiescent Current (10 Year Life) Programmable Setup and Calibration Programmable System Features Integrated Horn Driver with Tone Select and Hush Interconnect with Alarm Memory Internal Low Battery and Chamber Test Long Term Drift Adjust & 10 Yr. EOL 2 This low voltage smoke detector IC allows battery operation using 2 alkaline batteries or lithium batteries. The IC can operate from 5 Volts down to 2 Volts. The low quiescent current allows the IC to operate for 10 Yrs using lithium batteries. Programmable setup allows a range Infrared LEDs, photodiodes, and batteries to be used. Programmable calibration provides adjustment for the overall system performance including photo chamber performance. Programmable system features such as horn pattern select, low battery hush enable, long term drift enable, end of life enable, and hush option allow the smoke detector system design to meet specific regulatory requirements and to provide a range of model features with a single IC. The integrated horn driver with boost regulator allows the battery operated device to meet regulatory sound requirements down to 2V. The interconnect of up to 40 devices with local alarm memory allows the source of nuisance alarms to be easily identified in larger alarm configurations. System self checks such as low battery and chamber test insure proper operation of the smoke detector over its operating life. Long term drift adjustment allows the smoke detector system to compensate for component aging or chamber contamination. The end of life indicator provides an indication that the system needs to be replaced. 2
3 Analo g&interface ProductDivisio n VBS HSHBLX IRC FE GLE IO VSIRNRLE AP 3VDTES SOI IRE IRPDe vicepi VSm RD CT2 nout E46 ok C19 ed 0etec tori.c. The RE46C190 is provided in a 16 pin SOIC package. 3
Unique Strengths Programmable Setup and Calibration So What: The customer has greater freedom in component selection and system design. The programmable IR LED current and photodiode amplifier gain factor and integration time allow a range of IR LED s and photodiodes to be used. Programmable calibration allows the total system performance to be optimized. Manual system adjustment is eliminated. 4 The IC provides programmable setup and calibration. The Infrared LED current has 4 possible values from 50mA to 200mA in 50mA steps. The photo amplifier gain factor can be set from 1 to 4 in steps of 1. The photo amplifier integration time has 4 possible settings from 100 microseconds to 400 microseconds in 100 microsecond steps. The four alarm thresholds have 32 possible settings each. The low battery threshold adjustment provides 8 different thresholds to accommodate different types of batteries. Manual calibration in manufacturing is eliminated. 4
Unique Strengths Programmable System Features So What: One part can meet multiple model and regional requirements. Programmable system features allow smoke detectors to conform to different regional regulatory requirements. The smoke detector manufacturer can also program different model features with a single part. 5 Programmable features include tone select, low battery hush enable, hush enable, end of life (EOL) enable, long term drift enable. One part can meet multiple model and regional regulatory requirements. 5
Unique Strengths Low Voltage Battery Operation So What: The RE46C190 will operate down to 2.0V which allows operation from low voltage batteries. The programmable low battery voltage detection allows the customer to tailor the system performance to a specific type of battery. 6 Different battery chemistries produce different cell voltages and have different discharge characteristics. The low battery threshold is selectable in eight 100 mv steps from 2.1 to 2.8 volts with a tolerance of 50 mv for each step. The low battery alarm can be disabled for 8 hours if this option is selected since the low battery alarm can become very annoying quickly. 6
Unique Strengths Integrated Horn Driver with Selectable Horn Pattern and Hush So What: Loudness requirements can be met at 2V. The horn driver includes a boost regulator which allows the horn to meet regulatory sound pressure requirements. The temporal and continuous horn patterns are programmable as is hush operation. 7 Nine volts is typically required to achieve the necessary piezo horn sound pressure level or volume when the alarm sounds. A boost regulator provides power to the horn driver so the horn will produce the necessary volume. There are 2 horn patterns, continuous and temporal which can be selected depending on regulatory requirements. In addition the boost regulator provides additional headroom for the operation of the infrared LED during low battery conditions insuring consistent operation over battery life. 7
Unique Strengths Long Term Drift Adjustment So What: Component aging and/or chamber degradation can shift desired smoke detector characteristics. When enabled the long term drift adjustment compensates for these shifts in the smoke detector operation. The programmability of the IC makes this feature possible. 8 During calibration a no smoke baseline measurement is made and stored in EEPROM. When the long term drift adjustment is enabled, 64 baseline measurements are made over an 8 hour period. This information is compared to the baseline information stored in EEPROM at calibration and a correction factor is calculated to adjust the alarm thresholds. 8
Unique Strengths EOL (End Of Life) So What: Li battery and component aging may affect may affect smoke detector effectiveness. When this feature is enabled a 10 year counter is enabled while the part is powered on. When the 10 year limit is reached an alarm will sound. 9 The End of Life feature addresses concerns that after 10 years of powered operation, the smoke detector may not be as effective as needed and should be replaced. This feature is considered especially necessary when the smoke detector is powered by a lithium battery which will allow the smoke detector to operate for 10 years without battery replacement. 9
Unique Strengths Reduced Component Count So What: The RE46C190 includes much of the external circuitry needed by previous products provided by Microchip and its competitors. The typical application schematics below illustrate the difference. 10 Components for the gain, alarm thresholds, oscillator and infrared LED biasing have been eliminated. A previous generation smoke detector IC is shown next with the additional components required shown in red. The typical application schematic for the RE46C190 with reduced component is shown next. 10
Unique Strengths 11 The 17 components highlighted in red have been incorporated into the RE46C190 IC. The potentiometer, R2, provides manual calibration adjustment. R7 will adjust the infrared LED current. Capacitors C4 and C5 provide the necessary gain setting for the photodiode current. RADJ1 and RADJ2 are used to set the low battery threshold. R9, R12 and C8 set the oscillator frequency. The boost regulator and horn driver provide the required drive to the piezo horn. 11
Unique Strengths 12 This schematic shows the components necessary to implement a full featured three volt smoke detector using the RE46C190. 12
Features, Benefits, Results Feature Benefits Results Low Voltage Operation Low Quiescent Current Programmable Setup Programmable Calibration Programmable Features Integrated Horn Driver with selectable horn patterns and hush Allows low voltage battery operation with extended battery life Allows a wider selection of IR LED s, photodiodes, and batteries for use with a single smoke detector IC Allows different model and regulatory requirements to be met with a single IC A single smoke detector IC provides a complete system solution Eliminates the need for 9V batteries and allows for 10year operation with a LI battery Flexible design options and reduced parts inventory required. Manual calibration eliminated. Reduced parts inventory and manufacturing requirements Reduced parts inventory and manufacturing requirements 13 Low voltage operation and low quiescent current allows low voltage battery operation with extended battery life This eliminates the need for 9V batteries and allows for 10year operation with a lithium battery. Programmable Setup and Programmable Calibration allows a wider selection of infrared LED s, photodiodes, and batteries for use with a single smoke detector IC. This results in flexible design options with a single IC and reduced parts inventory required. Manual calibration is also eliminated. Programmable features allow different model and regulatory requirements to be met with a single IC. This reduces parts inventory and manufacturing requirements. The integrated horn driver with selectable horn patterns and hush allows a single smoke detector IC to provide a complete system solution with reduced parts inventory and manufacturing requirements 13
Features, Benefits, Results Feature Benefits Results Interconnect with Alarm Memory Interconnect Digital Filter Interconnect Charge Dump Low Battery Test with Hush Chamber Test Remembers if tripped making it easy to determine which device set off the group. Signal on Interconnect line will not cause false alarms and interconnect line quickly cleared when coming out of alarm state. Test battery for proper operating voltage and hush when necessary Insure proper operation of the photo chamber Defective unit or bad location (for example, by or in a Kitchen or bathroom) can be found. Smoke Alarm will not incorrectly sound on CO event and comes out of alarm state more quickly. Insures proper operation of the smoke detector Insures proper operation of the smoke detector 14 Interconnect with Alarm Memory allows the IC to remember if it was tripped making it easy to determine which device set off the group of smoke detectors. This allows a defective unit or bad location (for example, by or in a Kitchen or bathroom) to be found easily. The Interconnect Digital Filter prevents a carbon monoxide signal on the interconnect line from causing a false alarm. The Interconnect Charge Dump allows the interconnect line to be quickly cleared when coming out of alarm state. The Low Battery Test with Hush allows the battery to be tested for proper operating voltage and allows the low battery alarm to be silenced when necessary. This feature warns the user that the smoke detector is not properly powered. The Chamber Test warns that the smoke detector is not operating properly and allows the end user to replace a defective unit. 14
Features, Benefits, Results Feature Benefits Results Long Term Drift Adjustment EOL (End of Life Alarm) Reduced Component Count Corrects for component aging or drift Warns that the smoke detector is 10 years old Reduced inventory and manufacturing costs Insure proper operation of the smoke detector Warns the smoke detector should be replaced Improved margins 15 The Long Term Drift Adjustment corrects for component aging or drift. This insures the proper operation of the smoke detector. The End of Life Alarm warns that the smoke detector is 10 years old and that the smoke detector should be replaced. The Reduced Component Count leads to reduced inventory and manufacturing costs and improved margins. 15
Part Numbering Base Part Number: 190 3V, E-Cal, E Highly Integrated, Alarm Memory Photo Smoke Detection RE: Detector Products RE46C190S16TF T&R Pb free Part Type: 46C: Standard (not a custom) Package: S16: SOIC-16 16 The RE46C190 is a standard product provided in a lead free 16 pin SOIC package which can be taped and reeled. 16
Availability Data Sheet available at www.microchip.com Pricing in Price Book: US$0.94, each in 10k-unit quantities. Sampling available today at: http://sample.microchip.com Volume production available today at: www.microchipdirect.com 17 Please visit www.microchip.com for the data sheet and additional details. Samples are available at sample.microchip.com and the product can be purchased online at www.microchipdirect.com. Microchip has made a concerted effort to support the needs of the Smoke Detector industry. From low power operational amplifiers and power management products to the PICmicro and dedicated Smoke Detector I.C.s like the ones we are introducing here look to Microchip for Smoke Detector support. 17
Thank You Thank you for your time. 18