atmega4809 building the next generation smart,...

Building the Next Generation Smart, Secure and

Connected Air Quality Monitor

Introduction

Author: Namrata Dalvi, Ankit Phougat, Microchip Technology Inc.

The indoor air quality is a major concern in offices and houses due to the significant impact of air pollutionon health, comfort, well-being, and productivity of the occupants. The World Health Organization (WHO)estimates that around seven million people die every year from exposure to fine particles in the pollutedair that affects the lungs and the cardiovascular system, causing diseases such as stroke, heart disease,lung cancer, chronic obstructive pulmonary diseases and respiratory infections, including pneumonia.Hence, it is essential to have good air quality monitor systems at offices and at home for constant airquality monitoring. The Air Quality Monitor (AQM) is a real-time monitoring system, which measures mainairborne contaminants: Particulate Matter (PM2.5), Carbon Dioxide (CO2), humidity and temperaturelevels of the indoor air. The smart and secure AQMs can transmit the measured air quality data to a cloudserver or a smartphone over the internet or through a wireless communication medium. The AQM datacan also be sent to the HVAC control system inside buildings and homes or to other air monitoringsystems to control the air purification system. The air quality data can also be used for the earlymaintenance of the indoor air delivery systems.

This white paper describes how an AQM can take advantage of the Microchip megaAVR®

microcontroller’s core independent peripherals (CIPs), intelligent analog peripherals, and highlights theease of configuring CIPs using Atmel START and MPLAB® Code Configuration (MCC). ACryptoAuthentication™ secure element (ATECC608A) and a fully-certified Wi-Fi® module (ATWINC1510)can be used to connect the smart AQM to the Wi-Fi and cloud securely.

© 2019 Microchip Technology Inc. 00003017A-page 1

1. Air Quality Monitor RequirementsAn Air Quality Monitor (AQM) shall measure PM2.5 concentration levels and calculate Air Quality Index(AQI). The AQI can be used to determine the healthiness of the environmental air. The higher the AQIvalue, the greater the level of air pollution and health concern. For example, an AQI value of 50represents good air quality with little potential to affect public health, while an AQI value over 300represents hazardous air quality. An AQI value of 100 corresponds to the national air quality standard forthe pollutant, which is the level the Environmental Protection Agency (EPA) has set to protect publichealth. AQI values below 100 are generally thought of as satisfactory. For certain sensitive people groupsair quality is unhealthy if AQI values are above 100 and for everyone if AQI is above 151. Refer to the ‘AirQuality Index Guide by Environmental Protection Agency’ in the References section for more details.

The generic specifications of an AQM are the following:

• Input Sensors:– CO2 (0 – 10000 ppm) (Good Air quality range 0-1000 ppm)– PM2.5 (Good Air quality range 0- 12 ug/m3) refer to ‘Air Quality Index Calculator’ in the

References section for more details– Humidity (0-100%)– Temperature (-40°C to +125°C)

Devices should be able to measure analog signals from the above mentioned sensors and processanalog signals with required noise filtering to get the desired signal.

• Low Power Battery-Operated Design: the devices should be portable and operate on a rechargeablebattery. It should use the battery effectively to maximize time between battery charge cycles and thusmaximizing the battery life. Adding USB power for device operation is beneficial since devices usethe USB power instead of batteries to maximize battery life.

• User Interface: Display, Status LED, Buzzer and User Keypad:– Display AQI and other measured signals and provide status to the user– Provision to configure measurement parameters like the measurement frequency of input

parameters, data logging, etc.• Real-Time Data Logging: the storage element and RTC should be provided so real-time data with

timestamp can be logged to check the trends of the measured input.• Wireless Connectivity: a wireless connected device can act as an IoT node, which can be accessed

by the HVAC control or air purifier systems to improve the indoor air quality. Also, the user canaccess data over Wi-Fi to know the air quality.

• Security – Authorize Access, Data Encryption: today, security is most important with devices havingWi-Fi connectivity to prevent unauthorized access. The communication between a device and acontrol system/server needs to be authenticated and encrypted for firmware upgrades and AQI data.

Air Quality Monitor Requirements


2. Conceptual Design of Air Quality MonitorThis section discusses the conceptual design of a smart, secure and wirelessly connected Air QualityMonitor (AQM) using the Microchip ATmega4809 microcontroller, a temperature sensor (MCP9808), aCryptoAuthentication™ secure element (ATECC608A), an EEPROM (24LC512) and a Wi-Fi module(ATWINC1510) for wireless connectivity.

An AQM can be implemented as shown in the figure below, using a particulate matter PM2.5 sensor, aCO2 sensor, a humidity sensor and a temperature sensor. The Air Quality Index (AQI) can be calculatedby measuring the periodic values of PM2.5. The AQI value, the CO2 level, the humidity and temperaturecan be displayed on the OLED display. The real-time AQI data can be stored in EEPROM and sent to thecloud using Wi-Fi.

Figure 2-1. Conceptual Block Diagram of Indoor Air Quality Monitor

The AQM measures main airborne contaminants (PM2.5), humidity and temperature levels of indoor airusing ADC (Analog-to-Digital Converter), RTC (Real-Time Counter), Event System and I2C peripherals ofthe microcontroller. A 3" OLED display with SPI interface can be used to display the processed sensordata. The real-time air quality data can be logged to the EEPROM as per user configuration and loggeddata can be used to generate data trends. The processed air quality data can be sent wirelessly to asmartphone or to a cloud-based server through a Wi-Fi module interfaced to the microcontroller over SPI.The wireless messages can be encrypted using the CryptoAuthentication™ secure device for security.

Conceptual Design of Air Quality Monitor


Improving Noise Filtering in Sensor Node Applications

The sensor node application such as AQM mainly involves measuring analog signals from varioussensors. In the ideal case of a completely noiseless signal, achieving a high-quality digital representationof the signal is simple (single ADC conversions triggered with a fixed time interval are enough). But mostanalog signals are affected by noise. A potential solution could be to filter the acquired ADC samples insoftware, but this would require additional CPU resources. The ATmega4809 device features asuccessive approximation Analog-to-Digital Converter (ADC) with a maximum conversion rate of 150ksps with 8-bit resolution, or 115 ksps with 10-bit resolution. The ADC measurements can be doneagainst a selection of internal voltage references (0.55V, 1.1V, 1.5V, 2.5V and 4.3V) or directly againstVDD. This ADC has built-in noise filtering capabilities. The noise countermeasures supported by the ADCare:

• Hardware sample accumulator: the ADC can be configured to automatically accumulate a number of(up to 64) sampling results for a single conversion trigger.

• Sampling delay: inserts delay cycles between consecutive ADC conversions. When used togetherwith hardware sample accumulation, the sampling delay can be used to de-alias the ADC burstingfrequency from harmonic noise frequency components present in the sampled analog signal.

• Automatic sampling delay variation (ASDV): together with sample accumulation, ASDV can behelpful in suppressing harmonic noise with an unknown base frequency.

Periodic Sensor Measurements

The user can configure the time interval for taking input sensor measurements periodically. Themicrocontroller can configure the available 16-bit RTC to provide periodic event to start the ADCconversion. The megaAVR® 0-series microcontroller is equipped with RTC which can run continuously oninternal or external clock, in low-power Sleep modes, keep track of time and wake up the device fromSleep modes and/or interrupt the device at regular intervals.

Automated Periodic Start of ADC Conversion Providing Enhanced System Flexibility

The Event System peripheral is a core independent peripheral (CIP) in megaAVR 0-seriesmicrocontrollers that can reroute the RTC event to ADC and can trigger the ADC conversionautomatically.

The Event System features are listed below:

• Allows a change in one peripheral (the event generator) to trigger actions in other peripherals (theevent users) through event channels.

• Autonomous control of peripherals without any use of interrupts, CPU or DMA.• Provides short and predictable response times between peripherals and can reduce the complexity,

size, and execution time of the software and save power.

Temperature Measurement

The temperature plays a very important role to make a comfortable environment for the occupants. Thetemperature sensor MCP9808 from Microchip can be used to measure the ambient temperature. Therange of temperature measurement is between -20°C to +100°C with ±0.5°C accuracy and it can beinterfaced to the microcontroller using TWI (I2C) interface.

User Interface

LEDs and buzzers can be used to provide status and alarm conditions. A keypad can be provided foruser configurations. Logic and math peripheral - Configurable Custom Logic (CCL) - is a programmablelogic peripheral that can serve as ‘glue logic’ between the microcontroller peripherals and externaldevices. It can be connected to a wide range of internal and external inputs such as microcontroller pins,



events, or other internal peripherals. The CCL can be used for a variety of system tasks, ranging fromsimple digital signal inversion to complex event sequencing. CCL can handle the key press anddebounce the logic of the keypad.

Security and Connectivity

When connectivity comes to discussion, security is the major concern. Security can be added to aproduct by providing message encryption and decryption. Microchip provides modules for both securityand wireless communication, which will significantly reduce certification time and the amount of timerequired to get the new product to market. An example of such a secure element is Microchip’sATECC608A device. This device handles all the tasks associated with the authentication and securestorage of keys and certificates, delivering a secure solution without requiring any code writing. Similarly,certified wireless modules (ATWINC1510) execute everything needed to connect securely to a wirelessnetwork; the security protocols supported are WPA/WPA2 Personal and Enterprise, TLS and SSL. Themodules include all the necessary pieces of code and generally are controlled by simple commands sentover a serial interface like UART, SPI or I2C.

Enhanced Safety and Monitoring with Cyclic Redundancy Check and Memory Scan (CRCSCAN)

The hardware peripheral CRCSCAN can be used to detect errors in the program memory with theCRC-16-CCITT polynomial. CARSACN can be used for checking of the entire Flash section, applicationcode, and/or boot section.

Low-Power Battery Operated Design

The system can be powered up using an external power source such as USB power or a Li-Ion/Li/Polymer rechargeable battery. The battery power can be used to ensure that disturbances to the powernet does not take away the safety that the AQM provides. The megaAVR® 0-series microcontroller hassleep currents as low as 0.1 µA in Power-Down mode with VDD as 3VDC and all peripherals stopped inorder to be suited for battery-powered applications where performance and power consumption must beoptimized to extend battery life.

To charge the Li-Ion/Li/Polymer battery, Microchip’s USB battery charger with power path management ICMCP73871 can be used. The power supply section can have two power rails, 5 VDC (for various sensors)and 3.3 VDC (for the microcontroller and Wi-Fi module). A boost converter (MCP16251) can be used togenerate 5 VDC while 3.3 VDC can be generated using an LDO (MIC2951).

Extending AQM for Other Useful Applications

The indoor air quality monitor can be a very good example of an IoT sensor node using the Wi-Fi/BLEconnectivity and useful in hospitals, indoors and workplaces to monitor the air quality. This application canbe extended to the LPG detection in kitchens and control gas valves. Furthermore, the design can beupgraded to measure outdoor air quality through more sensors that detect hazardous gases such asCarbon Monoxide (CO), Nitrogen Dioxide (NO2), Ozone (O3), Sulphur Dioxide (SO2) and Volatile organiccompunds (VOCs), having analog interface with microcontrollers using ADC or digital interface such asI2C.



3. Faster Time to Market with Configurators and Development ToolsSupportTo simplify the embedded design process and to accelerate time to market, Microchip provides variousdevelopment boards such as the AVR-IoT WG Development Board, the ATmega4809 Xplained ProEvaluation Kit and the Curiosity Nano Evaluation Board and also software configuration tools such asAtmel START and MPLAB Code Configurator (MCC).

AVR-IoT WG Development Board

The AVR-IoT WG Development Board is equipped with the ATmega4808 microcontroller, an ATECC608ACryptoAuthentication™ secure element IC and the fully-certified ATWINC1510 Wi-Fi® network controllerfor secure and easy-to-deploy IoT connectivity. It provides the most simple and effective way to connectthe embedded application to Google’s Cloud IoT core platform. The board has an on-board debugger andrequires no external hardware to program and debug the microcontroller. It is supported by two award-winning Integrated Development Environments (IDEs): Atmel Studio and Microchip MPLAB® X IDE. Theuser can easily generate code for peripherals using the free software libraries in Atmel START or MCC.The board has an on-board light sensor and a temperature sensor (MCP9808). It has a mikroBUS™

connector to connect various MikroElektronika Click boards™ such as Air Quality Click useful for the proofof concept implementation of indoor AQM.

Figure 3-1. AVR-IoT WG Development Board

ATmega4809 Xplained Pro Evaluation Kit

The ATmega4809 Xplained Pro is a feature-rich evaluation board that can be used to start thedevelopment of projects. The board is equipped with an ATECC508 cryptoAuthentication device, threeXplained Pro Extension Headers, a mikroBUS™ socket, an embedded debugger for programming anddebugging, including power measurements, a data Gateway Interface, SPI, I2C, four GPIOs and a virtualCOM port (CDC).

Faster Time to Market with Configurators and ...


Figure 3-2. ATmega4809 Xplained Pro Evaluation kit

MCU Peripheral Configuration and Software Library Modules with Atmel START or MCC

• START is an intuitive, web-based tool that enables the configuration of microcontroller peripheralsand application code through a Graphical User Interface (GUI) reducing significantly the designdevelopment time of the embedded projects. START generates factory-validated C code to help getthe design started quickly. With a few clicks, START projects can be imported into the Atmel StudioIntegrated Development Environment (IDE) and can be easily modified at any time.

• megaAVR 0-series devices are now supported by the MPLAB Code Configurator (MCC). This freeplug-in with the MPLAB® X Integrated Development Environment (IDE) or the cloud-based MPLAB®

Xpress IDE provides a graphical programming environment that generates seamless, easy-to-understand C code. Using an intuitive interface, it enables and configures a rich set of peripheralsand functions specific to the application.

• Microchip provides certified software modules for security, wireless connectivity, bootloaders, I2CEEPROM, or temperature sensors.

Faster Time to Market with Configurators and ...


4. ConclusionThis white paper covers a conceptual design of an AQM using Microchip components. It also discusseshow design complexity in the hardware and the load over CPU can be reduced by using a state-of-the-artmicrocontroller (ATmega4809), and its CIPs like Event System, CCL, CRCSCAN and intelligent analogperipherals. These hardware-based peripherals allow the CPU to focus more on critical tasks, utilize lowpower, reduce design time and cost, increase safety and provide deterministic response in the system.The embedded design can be secured with the ATECC608A CryptoAuthentication™ secure elementwhich handles the authentication of each device. Wireless connectivity can be added to the design with afully-certified Wi-Fi® module (ATWINC1510). The development ecosystem formed of: Atmel Studio IDEwith built-in GCC complier, MPLAB® X IDE, and easy to use configuration tools like Atmel START andMCC, the AVR-IoT WG development board for cloud-connected devices and evalution kits like XplainedPro or Curiosity Nano enable users to build prototypes to validate designs and reach market faster thanbefore.

The rich feature set of the megaAVR® 0-series microcontrollers along with the easy-to-use developmenttool suite, CryptoAuthentication™ secure element, the fully-certified Wi-Fi® module, EEPROM, thetemperature sensor, the battery charger ICs, the boost converter controllers and LDOs make Microchipthe ideal solution provider for a wide variety of smart, secure and connected applications such as real-time control, sensor nodes, Internet of Things (IoT), industrial processing control and home appliances.

Conclusion


5. References1. Air Quality Index - A Guide to Air Quality and Your Health: https://airnow.gov/index.cfm?

action=aqi_brochure.index2. Air Quality Index - A Guide to Air Quality and Your Health Guide: https://www3.epa.gov/airnow/

aqi_brochure_02_14.pdf3. AQI Calculator: https://airnow.gov/index.cfm?action=airnow.calculator4. ATmega4809 Product Page: https://www.microchip.com/wwwproducts/en/ATMEGA48095. Introduction to CIPs: http://ww1.microchip.com/downloads/en/AppNotes/Getting-Started-with-

Peripherals-on-AVR-MCU-00002451C.pdf6. ADC Basics with AVR Microcontrollers: http://ww1.microchip.com/downloads/en/AppNotes/

AN2573-ADC-Basics-with-tinyAVR-and-megaAVR-00002573C.pdf7. Getting Started with megaAVR® 0-series: http://ww1.microchip.com/downloads/en/AppNotes/

Getting-Started-with-megaAVR-0-series-00002563B.pdf8. Noise Countermeasures for ADC Applications: http://ww1.microchip.com/downloads/en/AppNotes/

AN2551-Noise-Countermeasures-for-ADC-Applications-00002551C.pdf9. Create Smart, Secure Nodes for Google Cloud IoT with the AVR-IoT WG Development Board:

https://www.microchip.com/design-centers/internet-of-things/google-cloud-iot/avr-iot10. FreeRTOS™ with ATmega4809: http://ww1.microchip.com/downloads/en/AppNotes/AN2783-

FreeRTOS-Using-Percepio-Trace-on-ATmega4809-00002783A.pdf

References


https://airnow.gov/index.cfm?action=aqi_brochure.indexhttps://airnow.gov/index.cfm?action=aqi_brochure.indexhttps://www3.epa.gov/airnow/aqi_brochure_02_14.pdfhttps://www3.epa.gov/airnow/aqi_brochure_02_14.pdfhttps://airnow.gov/index.cfm?action=airnow.calculatorhttps://www.microchip.com/wwwproducts/en/ATMEGA4809http://ww1.microchip.com/downloads/en/AppNotes/Getting-Started-with-Peripherals-on-AVR-MCU-00002451C.pdfhttp://ww1.microchip.com/downloads/en/AppNotes/Getting-Started-with-Peripherals-on-AVR-MCU-00002451C.pdfhttp://ww1.microchip.com/downloads/en/AppNotes/AN2573-ADC-Basics-with-tinyAVR-and-megaAVR-00002573C.pdfhttp://ww1.microchip.com/downloads/en/AppNotes/AN2573-ADC-Basics-with-tinyAVR-and-megaAVR-00002573C.pdfhttp://ww1.microchip.com/downloads/en/AppNotes/Getting-Started-with-megaAVR-0-series-00002563B.pdfhttp://ww1.microchip.com/downloads/en/AppNotes/Getting-Started-with-megaAVR-0-series-00002563B.pdfhttp://ww1.microchip.com/downloads/en/AppNotes/AN2551-Noise-Countermeasures-for-ADC-Applications-00002551C.pdfhttp://ww1.microchip.com/downloads/en/AppNotes/AN2551-Noise-Countermeasures-for-ADC-Applications-00002551C.pdfhttps://www.microchip.com/design-centers/internet-of-things/google-cloud-iot/avr-iothttp://ww1.microchip.com/downloads/en/AppNotes/AN2783-FreeRTOS-Using-Percepio-Trace-on-ATmega4809-00002783A.pdfhttp://ww1.microchip.com/downloads/en/AppNotes/AN2783-FreeRTOS-Using-Percepio-Trace-on-ATmega4809-00002783A.pdf

The Microchip Web Site

Microchip provides online support via our web site at http://www.microchip.com/. This web site is used asa means to make files and information easily available to customers. Accessible by using your favoriteInternet browser, the web site contains the following information:

• Product Support – Data sheets and errata, application notes and sample programs, designresources, user’s guides and hardware support documents, latest software releases and archivedsoftware

• General Technical Support – Frequently Asked Questions (FAQ), technical support requests, onlinediscussion groups, Microchip consultant program member listing

• Business of Microchip – Product selector and ordering guides, latest Microchip press releases,listing of seminars and events, listings of Microchip sales offices, distributors and factoryrepresentatives

Customer Change Notification Service

Microchip’s customer notification service helps keep customers current on Microchip products.Subscribers will receive e-mail notification whenever there are changes, updates, revisions or erratarelated to a specified product family or development tool of interest.

To register, access the Microchip web site at http://www.microchip.com/. Under “Support”, click on“Customer Change Notification” and follow the registration instructions.

Customer Support

Users of Microchip products can receive assistance through several channels:

• Distributor or Representative• Local Sales Office• Field Application Engineer (FAE)• Technical Support

Customers should contact their distributor, representative or Field Application Engineer (FAE) for support.Local sales offices are also available to help customers. A listing of sales offices and locations is includedin the back of this document.

Technical support is available through the web site at: http://www.microchip.com/support

Microchip Devices Code Protection Feature

Note the following details of the code protection feature on Microchip devices:

• Microchip products meet the specification contained in their particular Microchip Data Sheet.• Microchip believes that its family of products is one of the most secure families of its kind on the

market today, when used in the intended manner and under normal conditions.• There are dishonest and possibly illegal methods used to breach the code protection feature. All of

these methods, to our knowledge, require using the Microchip products in a manner outside theoperating specifications contained in Microchip’s Data Sheets. Most likely, the person doing so isengaged in theft of intellectual property.

• Microchip is willing to work with the customer who is concerned about the integrity of their code.


http://www.microchip.com/http://www.microchip.com/http://www.microchip.com/support

• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of theircode. Code protection does not mean that we are guaranteeing the product as “unbreakable.”

Code protection is constantly evolving. We at Microchip are committed to continuously improving thecode protection features of our products. Attempts to break Microchip’s code protection feature may be aviolation of the Digital Millennium Copyright Act. If such acts allow unauthorized access to your softwareor other copyrighted work, you may have a right to sue for relief under that Act.

Legal Notice

Information contained in this publication regarding device applications and the like is provided only foryour convenience and may be superseded by updates. It is your responsibility to ensure that yourapplication meets with your specifications. MICROCHIP MAKES NO REPRESENTATIONS ORWARRANTIES OF ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORYOR OTHERWISE, RELATED TO THE INFORMATION, INCLUDING BUT NOT LIMITED TO ITSCONDITION, QUALITY, PERFORMANCE, MERCHANTABILITY OR FITNESS FOR PURPOSE.Microchip disclaims all liability arising from this information and its use. Use of Microchip devices in lifesupport and/or safety applications is entirely at the buyer’s risk, and the buyer agrees to defend,indemnify and hold harmless Microchip from any and all damages, claims, suits, or expenses resultingfrom such use. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectualproperty rights unless otherwise stated.

Trademarks

The Microchip name and logo, the Microchip logo, AnyRate, AVR, AVR logo, AVR Freaks, BitCloud,chipKIT, chipKIT logo, CryptoMemory, CryptoRF, dsPIC, FlashFlex, flexPWR, Heldo, JukeBlox, KeeLoq,Kleer, LANCheck, LINK MD, maXStylus, maXTouch, MediaLB, megaAVR, MOST, MOST logo, MPLAB,OptoLyzer, PIC, picoPower, PICSTART, PIC32 logo, Prochip Designer, QTouch, SAM-BA, SpyNIC, SST,SST Logo, SuperFlash, tinyAVR, UNI/O, and XMEGA are registered trademarks of Microchip TechnologyIncorporated in the U.S.A. and other countries.

ClockWorks, The Embedded Control Solutions Company, EtherSynch, Hyper Speed Control, HyperLightLoad, IntelliMOS, mTouch, Precision Edge, and Quiet-Wire are registered trademarks of MicrochipTechnology Incorporated in the U.S.A.

Adjacent Key Suppression, AKS, Analog-for-the-Digital Age, Any Capacitor, AnyIn, AnyOut, BodyCom,CodeGuard, CryptoAuthentication, CryptoAutomotive, CryptoCompanion, CryptoController, dsPICDEM,dsPICDEM.net, Dynamic Average Matching, DAM, ECAN, EtherGREEN, In-Circuit Serial Programming,ICSP, INICnet, Inter-Chip Connectivity, JitterBlocker, KleerNet, KleerNet logo, memBrain, Mindi, MiWi,motorBench, MPASM, MPF, MPLAB Certified logo, MPLIB, MPLINK, MultiTRAK, NetDetach, OmniscientCode Generation, PICDEM, PICDEM.net, PICkit, PICtail, PowerSmart, PureSilicon, QMatrix, REAL ICE,Ripple Blocker, SAM-ICE, Serial Quad I/O, SMART-I.S., SQI, SuperSwitcher, SuperSwitcher II, TotalEndurance, TSHARC, USBCheck, VariSense, ViewSpan, WiperLock, Wireless DNA, and ZENA aretrademarks of Microchip Technology Incorporated in the U.S.A. and other countries.

SQTP is a service mark of Microchip Technology Incorporated in the U.S.A.

Silicon Storage Technology is a registered trademark of Microchip Technology Inc. in other countries.

GestIC is a registered trademark of Microchip Technology Germany II GmbH & Co. KG, a subsidiary ofMicrochip Technology Inc., in other countries.

All other trademarks mentioned herein are property of their respective companies.


© 2019, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved.

ISBN: 978-1-5224-4421-3

Quality Management System Certified by DNV

ISO/TS 16949Microchip received ISO/TS-16949:2009 certification for its worldwide headquarters, design and waferfabrication facilities in Chandler and Tempe, Arizona; Gresham, Oregon and design centers in Californiaand India. The Company’s quality system processes and procedures are for its PIC® MCUs and dsPIC®

DSCs, KEELOQ® code hopping devices, Serial EEPROMs, microperipherals, nonvolatile memory andanalog products. In addition, Microchip’s quality system for the design and manufacture of developmentsystems is ISO 9001:2000 certified.


AMERICAS ASIA/PACIFIC ASIA/PACIFIC EUROPECorporate Office2355 West Chandler Blvd.Chandler, AZ 85224-6199Tel: 480-792-7200Fax: 480-792-7277Technical Support:http://www.microchip.com/supportWeb Address:www.microchip.comAtlantaDuluth, GATel: 678-957-9614Fax: 678-957-1455Austin, TXTel: 512-257-3370BostonWestborough, MATel: 774-760-0087Fax: 774-760-0088ChicagoItasca, ILTel: 630-285-0071Fax: 630-285-0075DallasAddison, TXTel: 972-818-7423Fax: 972-818-2924DetroitNovi, MITel: 248-848-4000Houston, TXTel: 281-894-5983IndianapolisNoblesville, INTel: 317-773-8323Fax: 317-773-5453Tel: 317-536-2380Los AngelesMission Viejo, CATel: 949-462-9523Fax: 949-462-9608Tel: 951-273-7800Raleigh, NCTel: 919-844-7510New York, NYTel: 631-435-6000San Jose, CATel: 408-735-9110Tel: 408-436-4270Canada - TorontoTel: 905-695-1980Fax: 905-695-2078

Australia - SydneyTel: 61-2-9868-6733China - BeijingTel: 86-10-8569-7000China - ChengduTel: 86-28-8665-5511China - ChongqingTel: 86-23-8980-9588China - DongguanTel: 86-769-8702-9880China - GuangzhouTel: 86-20-8755-8029China - HangzhouTel: 86-571-8792-8115China - Hong Kong SARTel: 852-2943-5100China - NanjingTel: 86-25-8473-2460China - QingdaoTel: 86-532-8502-7355China - ShanghaiTel: 86-21-3326-8000China - ShenyangTel: 86-24-2334-2829China - ShenzhenTel: 86-755-8864-2200China - SuzhouTel: 86-186-6233-1526China - WuhanTel: 86-27-5980-5300China - XianTel: 86-29-8833-7252China - XiamenTel: 86-592-2388138China - ZhuhaiTel: 86-756-3210040

India - BangaloreTel: 91-80-3090-4444India - New DelhiTel: 91-11-4160-8631India - PuneTel: 91-20-4121-0141Japan - OsakaTel: 81-6-6152-7160Japan - TokyoTel: 81-3-6880- 3770Korea - DaeguTel: 82-53-744-4301Korea - SeoulTel: 82-2-554-7200Malaysia - Kuala LumpurTel: 60-3-7651-7906Malaysia - PenangTel: 60-4-227-8870Philippines - ManilaTel: 63-2-634-9065SingaporeTel: 65-6334-8870Taiwan - Hsin ChuTel: 886-3-577-8366Taiwan - KaohsiungTel: 886-7-213-7830Taiwan - TaipeiTel: 886-2-2508-8600Thailand - BangkokTel: 66-2-694-1351Vietnam - Ho Chi MinhTel: 84-28-5448-2100

Austria - WelsTel: 43-7242-2244-39Fax: 43-7242-2244-393Denmark - CopenhagenTel: 45-4450-2828Fax: 45-4485-2829Finland - EspooTel: 358-9-4520-820France - ParisTel: 33-1-69-53-63-20Fax: 33-1-69-30-90-79Germany - GarchingTel: 49-8931-9700Germany - HaanTel: 49-2129-3766400Germany - HeilbronnTel: 49-7131-67-3636Germany - KarlsruheTel: 49-721-625370Germany - MunichTel: 49-89-627-144-0Fax: 49-89-627-144-44Germany - RosenheimTel: 49-8031-354-560Israel - Ra’ananaTel: 972-9-744-7705Italy - MilanTel: 39-0331-742611Fax: 39-0331-466781Italy - PadovaTel: 39-049-7625286Netherlands - DrunenTel: 31-416-690399Fax: 31-416-690340Norway - TrondheimTel: 47-72884388Poland - WarsawTel: 48-22-3325737Romania - BucharestTel: 40-21-407-87-50Spain - MadridTel: 34-91-708-08-90Fax: 34-91-708-08-91Sweden - GothenbergTel: 46-31-704-60-40Sweden - StockholmTel: 46-8-5090-4654UK - WokinghamTel: 44-118-921-5800Fax: 44-118-921-5820

Worldwide Sales and Service


Introduction1. Air Quality Monitor Requirements2. Conceptual Design of Air Quality Monitor3. Faster Time to Market with Configurators and Development Tools Support4. Conclusion5. ReferencesThe Microchip Web SiteCustomer Change Notification ServiceCustomer SupportMicrochip Devices Code Protection FeatureLegal NoticeTrademarksQuality Management System Certified by DNVWorldwide Sales and Service

atmega4809 building the next generation smart,...

Documents