Smoke Detection Systems

The ADPD188BI is a complete photometric system for smoke detection using optical dual wavelength technology. The module integrates a highly efficient photometric front end, two light emitting diodes (LEDs), and two photodiodes (PDs). These items are housed in a custom package that prevents light from going directly from the LED to the photodiode without first entering the smoke detection chamber.

The front end of the application specific integrated circuit (ASIC) consists of a control block, a 14-bit analog-to-digital converter (ADC) with a 20-bit burst accumulator, and three flexible, independently configurable LED drivers. The control circuitry includes flexible LED signaling and synchronous detection. The analog front end (AFE) features best-in-class rejection of signal offset and corruption due to modulated interference commonly caused by ambient light. The data output and functional configuration occur over a 1.8 V I²C interface or serial peripheral interface (SPI) port.

Applications

• Smoke Detection

The ADPD1080/ADPD1081 are highly efficient, photometric front ends, each with an integrated 14-bit analog-to-digital converter (ADC) and a 20-bit burst accumulator that works with flexible light emitting diode (LED) drivers. The ADPD1080/ADPD1081 stimulate an LED and measures the corresponding optical return signal. The data output and functional configuration occur over a 1.8 V I²C interface on the ADPD1080 or a serial port interface (SPI) on the ADPD1081. The control circuitry includes flexible LED signaling and synchronous detection.

The analog front end (AFE) features rejection of signal offset and corruption due to modulated interference commonly caused by ambient light without the need for optical filters or dc cancellation circuitry that requires external control.

Couple the ADPD1080/ADPD1081 with a low capacitance photodiode of <100 pF for optimal performance. The ADPD1080/ADPD1081 can be used with any LED. The ADPD1080 is available in a 16-ball, 2.46 mm × 1.4 mm WLCSP and a 28-lead, 4 mm × 4 mm LFCSP. The SPI only version, ADPD1081, is available in a 17-ball, 2.46 mm × 1.4 mm WLCSP.

Applications

• Wearable health and fitness monitors
• Clinical measurements, for example, SpO₂
• Industrial monitoring
• Background light measurements

The ADuM7440 / ADuM7441 / ADuM7442 are 4-channel digital isolators based on the Analog Devices, Inc., iCoupler^® technology. Combining high speed CMOS and monolithic air core transformer technologies, these isolation components provide outstanding performance characteristics superior to the alternatives, such as optocoupler devices and other integrated couplers.

The ADuM7440 / ADuM7441 / ADuM7442 family of quad 1 kV digital isolation devices is packaged in a small 16-lead QSOP. While most 4-channel isolators come in 16-lead wide SOIC packages, the ADuM7440 / ADuM7441 / ADuM7442 free almost 70% of board space and yet can still withstand high isolation voltage and meet UL regulatory requirements. In addition to the space savings, the ADuM7440 / ADuM7441 / ADuM7442 offer a lower price than 2.5 kV or 5 kV isolators where only functional isolation is needed.

This family, like many Analog Devices isolators, offers very low power consumption, consuming one-tenth to one-sixth the power of comparable isolators at comparable data rates up to 25 Mbps. Despite the low power consumption, all models of the ADuM7440 / ADuM7441 / ADuM7442 provide low pulse width distortion (<5 ns for C grade). In addition, every model has an input glitch filter to protect against extraneous noise disturbances.

The ADuM7440 / ADuM7441 / ADuM7442 isolators provide four independent isolation channels in a variety of channel configurations and two data rates (see the Ordering Guide) up to 25 Mbps. All models operate with the supply voltage on either side ranging from 3.0 V to 5.5 V, providing compatibility with lower voltage systems as well as enabling voltage translation functionality across the isolation barrier. All products also have an output default high logic state in the absence of the input power.

APPLICATIONS

• General-purpose, multichannel isolation
• SPI interface/data converter isolation
• RS-232/RS-422/RS-485 transceivers
• Industrial field bus isolation

The LT3009 Series are micropower, low dropout voltage (LDO) linear regulators. The devices supply 20mA output current with a dropout voltage of 280mV. No-load quiescent current is 3μA. Ground pin current remains at less than 5% of output current as load increases. In shutdown, quiescent current is less than 1μA.

The LT3009 regulators optimize stability and transient response with low ESR ceramic capacitors, requiring a minimum of only 1μF. The regulators do not require the . addition of ESR as is common with other regulators. Internal protection circuitry includes current limiting, thermal limiting, reverse-battery protection and reverse-current protection.

The LT3009 Series are ideal for applications that require moderate output drive capability coupled with ultralow standby power consumption. The device is available in fixed output voltages of 1.2V, 1.5V, 1.8V, 2.5V, 3.3V and 5V, and as an adjustable device with an output voltage range down to the 600mV reference. The LT3009 is available in the 6-lead DFN and 8-lead SC70 packages.

Applications

• Low Current Battery-Powered Systems
• Keep-Alive Power Supplies
• Remote Monitoring
  • Utility Meters
  • Hotel Door Locks

The LTC3130/LTC3130-1 are high efficiency, low noise, 600mA buck-boost converters with wide V_IN and V_OUT ranges. For high efficiency operation at light loads, BurstMode operation can be selected, reducing the quiescent current to just 1.6µA. Converter start-up is achieved from sources as low as 7.5µW.

TheLTC3130/LTC3130-1 employ an ultralow noise, 1.2MHz PWM architecture that minimizes solution footprint by allowing the use of tiny, low profile inductors and ceramic capacitors. Built-in loop compensation and soft-start reduces external parts count and simplifies the design. Features include an accurate RUN comparator threshold to allow predictable regulator turn-on and a maximum power point control (MPPC) capability that ensures maximum power extraction from non-ideal sources such as photovoltaic panels. The LTC3130-1 includes an internal voltage divider to provide four selectable fixed output voltages.

Additional features include a power good output, an external V_CC input and thermal shutdown.

The LTC3130 and LTC3130-1 are available in thermally-enhanced 20-lead 3mm × 4mm QFN and 16-lead MSOP packages.

Applications

• Long-Life, Battery-Operated Instruments
• Portable Military Radios
• Low Power Sensors
• Solar Panel Post-Regulator/Charger

The MAX31875 is a ±1°C-accurate local temperature sensor with I²C/SMBus interface. The combination of tinypackage and excellent temperature measurement accuracymakes this product ideal for a variety of equipment.

The I²C/SMBus-compatible serial interface accepts standard write byte, read byte, send byte, and receive byte commands to read the temperature data and configure the behavior of the sensor. Bus timeout resets the interface if the clock is low for more than 30ms (nominal). PEC helps to avoid communication errors when used with a master that supports this feature.

The MAX31875 is available in a 4-bump, wafer-level package (WLP) and operates over the -50°C to +150°C temperature range.

Applications

• Battery-Powered Equipment
• Data Communications Equipment
• Handheld Electronics
• Industrial Equipment
• Servers

In the DARWIN family, the MAX32660 is an ultra-low-power, cost-effective, highly-integrated 32-bit microcontroller designed for battery-powered devices and wireless sensors. It combines a flexible and versatile power management unit with the powerful Arm^® Cortex^®-M4 processor with floating point unit (FPU) in the industry’s smallest form factor: 1.6mm x 1.6mm, 16-bump WLP or 4mm x 4mm, 20-pin TQFN-EP, or 3mm x 3mm, 24-pin TQFN-EP.

The MAX32660 enables designs with complex sensor processing without compromising battery life. It also offers legacy designs an easy and cost optimal upgrade path from 8- or 16-bit microcontrollers.

The device supports SPI, UART, and I²C communication while also integrating up to 256KB of flash memory and 96KB of RAM to accommodate application and sensor code. An optional bootloader through I²C, UART, or SPI is available.

OnDemand Webinar: What Can you Do with the World’s Smallest Arm^® Cortex^® M4 with FPU Microcontroller?

Applications

• Fitness Monitors
• Industrial Sensors
• IoT
• Optical Modules: QSFP-DD, QSFP, 400G
• Portable Medical Devices
• Sports Watches
• Wearable Medical Patches

The EVAL-ADPD1080Z-PRX evaluation kit provides users with a simple means of connecting with the ADPD1080 hardware, collecting data from the ADPD1080, and evaluating long range proximity capabilities. The ADPD1080 hardware is configured with a large area, p-type, intrinsic, n-type (PIN) semiconductor photodiode as a proximity sensor. In this configuration, motion and proximity in front of the EVAL-ADPD1080Z-PRX are measured by detecting the amount of infrared (IR) light reflected off of objects and the change in IR light as objects move relative to the EVAL-ADPD1080Z-PRX.

The evaluation kit requires the EVAL-ADPDM3Z and the Applications Wavetool, which can be downloaded from the EVAL-ADPD1080Z-PRX product page. The Applications Wavetool is a graphical user interface (GUI) that provides users with low level and high level configurability, real-time data analysis, and user datagram protocol (UDP) transfer capabilities so that the evaluation board can easily connect to a PC.

The USB port of the PC powers the EVAL-ADPDM3Z and the EVAL-ADPD1080Z-PRX. On-board voltage regulators provide voltage supplies for the ADPD1080.

The evaluation board schematic indicates signal names for easy identification.

Full specifications for the ADPD1080 are available in the ADPD1080 data sheet. Refer to both this data sheet and the EVAL-ADPD1080Z-PRX user guide when working with the evaluation board.

The EVAL-ADPD188BIZ-S2 evaluation board provides users with a simple means of evaluating the ADPD188BI optical module along with the EVAL-CHAMBER smoke chamber for smoke and aerosol detection applications.

The evaluation system is composed of the EVAL-ADPD188BIZ-S2 evaluation board, the EVAL-ADPDUCZ microcontroller board, the optional EVAL-CHAMBER smoke chamber, and the Wavetool Evaluation Software graphical user interface (GUI). The software provides users with both low level and high level configurability, real-time frequency and time domain analysis, and user datagram protocol (UDP) transfer capability so that the evaluation board can easily interface to the user development system.

The EVAL-ADPD188BIZ-S2 is powered through the ribbon cable from the EVAL-ADPDUCZ microcontroller board (ordered separately).

For full details on the ADPD188BI, see the ADPD188BI data sheet, which should be consulted in conjunction with this user guide when using these evaluation boards.

Since the 1970s, smoke detectors have become commonplace in commercial and residential buildings. Two basic types of detectors exist today: the oldest technology is the ionization type that uses radioactive material to ionize the air and checks for an electrical imbalance, the second, newer technology is the photoelectric type that uses a light source aimed at an angle away from a photodetector (PD) and checks for photodetector current caused by the light reflecting from airborne particles to the photodiode. Between two types, the photoelectric smoke detector enjoys greater popularity due to its improved reliability in detecting common house fires and faster response times to smoldering fires.

Until recently, smoke detector technology and regulations have also remained virtually the same despite advances in electronics and common household materials throughout the decades. New revisions in standards, such as ANSI/UL 217 8th edition and ANSI/UL 268 7th edition, published by Underwriters Laboratory (UL) and the NFPA^® 72 National Fire Alarm Code, published by the National Fire Protection Agency (NFPA), aim to address this gap by updating the requirements for modern smoke detector designs. Other worldwide standards, such as EN 14604, EN 54, and ISO 7240 are likely to add similar tests to address this and other concerns in the future, making it more important to have advanced sensing capabilities and software-driven detection algorithms that can be adjusted to meet new requirements.

Fundamentally, these new regulations aim to reduce the incidents wherein a user may disable the smoke detector due to false alarms. Disabled smoke detectors lead to fire related deaths, so by reducing false alarms, smoke detectors are less likely to be manually disabled. New smoke detectors are required to tolerate a minimum quantity of nuisance smoke without alarming and must last 10 years on the installed battery.

The circuit shown in Figure 1 is a tested and verified smoke detector system-on-module (SOM) reference design with an available algorithm and data set. This system includes all of the components needed for standalone operation such as an on-board optical sensor, microcontroller, temperature sensor, and power regulators. The design of the SOM features castellated pins that allow it to be fitted into a carrier board or soldered directly to a custom application board for test and development.

Embedded software and algorithms are used to evaluate smoke and fire tests specified in 8th edition of the UL 217, 7th edition of the UL 268, and EN 14604 standards. These algorithms and data sets are available separately to help deploy your smoke detection solution faster. For customized algorithmic developments, additional data can be collected and added into the algorithm to adapt it for other standards.

UL-217 8th edition and EN14604:2005 certified algorithm was developed and passed the smoke/fire tests outlined in the standard. This algorithm will enable you to design your smoke detector applications faster and with more confidence, with the updated standards. Collecting more than 1000 sensor datasets at certified testing facilities provided a large statistical representation which the algorithm was trained and tuned. The accompanying embedded software initializes, calibrates, temperature compensates, pre-processes data, and implements the algorithm engine.

The EVAL-CN0583-SOM uses the ADPD188BI integrated optical sensor (with LED and PD) along with an optimized smoke chamber design to sense and measure smoke particles using a single calibrated device. The hardware design also can handle environmental nuisances, like humidity/dew, using heater resistors to dry the air inside the smoke chamber. The hardware can be used directly with many different microcontrollers, which provides features such as a buzzer, push button, LED indicator, and microSD slot for storing data.

The CN0583 reference design includes a complete data and software offering designed to accelerate smoke/fire detection application development.

The Data and Algorithm (EVAL-SMOKE-ALG) package provides an extensive (1000+) smoke dataset taken at UL-217 and EN14604 certified facilities for those who wish to develop their own algorithm. It includes the CN0583 source code for initialization, calibration, environmental compensation, data pre-processing and adds a UL & EN certified smoke detection algorithm and associated algorithm project files.

This reference design plus related software is designed and tested to meet UL 217/UL 268 and similar smoke/fire detection standards. To address the needs of different customers a number of solution offerings are available which are summarized in the table below. The hardware is Arduino form factor compatible and is designed to accelerate prototyping and the evaluation of the embedded smoke detection algorithm. The hardware is compromised of the EVAL-CN0537-ARDZ reference design which is described the CN0537 circuit note and the supporting EVAL-ADICUP3029 microcontroller board. The Data (EVAL-CN0537-DATA) package provides an extensive smoke dataset taken at UL certified facilities for those who wish to develop their own algorithm and the CN0537 source code - excluding the detection algorithm. The Algorithm (EVAL-CN0537-ALGO) package includes everything in the Data package and a UL certified smoke detection algorithm with associated algorithm project files.

Since the 1970s, smoke detectors have become commonplace in commercial and residential buildings. Two basic types of detectors exist today, the ionization type that uses radioactive matter to ionize the air and checks for an electrical imbalance, and the photoelectric type that uses a light source aimed at an angle away from a photodetector and checks for photodetector current caused by the light reflecting from airborne particles to the photodiode. Although a combination solution of both types is recommended, the photoelectric smoke detector is more popular due to its improved reliability in detecting common house fires and faster response times to smoldering fires.

Unfortunately, smoke detector technology and regulations have also remained virtually the same since the 1970s despite the advances in electronics and common household materials through the decades. New revisions in standards, such as ANSI/UL 217 and ANSI/UL 268, published by Underwriters Laboratory (UL), or the NFPA^® 72 National Fire Alarm Code, published by the National Fire Protection Agency (NFPA), aim to address this gap by placing more complex requirements on modern smoke detector designs. Other worldwide standards, such as EN 14604, EN 54, and ISO 7240 will likely add similar tests to address this and other concerns in the future, making it more important to have more advanced sensing capabilities.

The goal of these updated standards is to increase safety and decrease the number of fire related deaths by reducing the number of false alarms that are generated from everyday activity. For example, in addition to the traditional fire and smoke sensitivity tests, the 8th edition of UL 217 and the 7th edition of UL 268 now requires that smoke detectors do not produce a false alarm during nuisance events, like cooking. Therefore, modern smoke detectors must be able to distinguish between a cooking nuisance event and a fire event. Traditionally, this goal required a complicated solution with multiple sensor technologies and a level of artificial intelligence. However, the use of the ADPD188BI makes this solution significantly more simple to implement.

The circuit shown in Figure 1 is a tested and verified smoke detector reference design with an available algorithm and a data set based on the ADPD188BI optical module. For easy and rapid development, the design is made compatible with the Arduino form factor controller platforms. Software and embedded algorithms combined with the hardware can be used to evaluate smoke and fire tests specified in 8th edition of the UL 217 and the 7th edition of the UL 268 standards. Verified algorithms are available for direct use to help deploy the smoke detection solution faster, and additional data can also be collected and added into the algorithm to adapt it for other standards.

UL-217 8th edition certified algorithm was developed and passed the smoke/fire tests outlined in the standard. This algorithm will enable you to design your smoke detector applications faster and with more confidence, with the updated standards. Collecting more than 1000 sensor datasets at certified testing facilities provided a large statistical representation which the algorithm was trained and tuned. The accompanying embedded software initializes, calibrates, temperature compensates, pre-processes data, and implements the algorithm engine.

The EVAL-CN0537-ARDZ uses the ADPD188BI integrated optical sensor (with LED and PD) along with an optimized smoke chamber design to sense and measure smoke particles using a single calibrated device. The hardware design also can handle environmental nuisances, like humidity/dew, using heater resistors to dry the air inside the smoke chamber. The hardware is an Arduino form factor design and can be use used directly with many different microcontrollers, which provides features such as a buzzer, push button, LED indicator, and micro SD slot for storing data.

The CN0537 reference design includes a complete data and software offering designed to accelerate smoke/fire detection application development.

The Data (EVAL-CNO537-DATA) package provides an extensive (1000+) smoke dataset taken at UL-217 certified facilities for those who wish to develop their own algorithm. It includes the CN0537 source code for initialization, calibration, environmental compensation, data pre-processing - but excludes the detection algorithm.

The Algorithm (EVAL-CN0537-ALGO) package includes everything in the Data package and adds a UL certified smoke detection algorithm and associated algorithm project files.