Flame Detection

QFS SMD Sensor

QFS SMD Sensor

KEMET’s QFS pyroelectric flame sensors combine high sensitivity with fast response times and high dynamic range to ensure rapid and accurate detection of small and large flames, nearby or over larger distances. These high quality sensors, in their small SMD package, integrate a digital, current mode read-out offering high responsivity over the full frequency range of flame flicker from 3 – 30 Hz. Industry standard I2C communication enables plug-and-play connectivity to microcontrollers and allows easy tuning and calibration. Programmable gain and filtering offer maximum flexibility in system design, and various optical filter options are also available. These sensors can be connected together in a linear series for synchronized sampling across devices. Their long and maintenance-free operational lifetime and various low power modes make these sensors ideal for any smart or IoT type of application.

Part Number Filter Filter BW Use


2.20 μm Long pass Broadband flame detection  
USEQFSEA50L180 5.00 μm Long pass Human motion rejection  
USEQFSEA391180 3.91 μm 90 nm Rejection Channel  
USEQFSEA464180 4.64 μm 180 nm Flame channel (wide FoV)  
USEQFSEA448180 4.48 μm 620 nm Flame channel (main detector)  
Features and Benefits Field of View Applications for Rapid Fire Detection
  • High sensitivity with fast response time
  • High dynamic range
  • Small SMD package
  • I2C communication compatible and digital output
  • Programmable gain and filtering
  • Various optical filter options
  • Integrated configurable amplifier, filter, and ADC
  • Low power consumption
Flame Sensor Field of View
  • Industrial IoT
  • General manufacturing
  • Marine, transportation, and logistics
  • Smart home and building
  • Energy and power
  • Retail
  • Healthcare


The Flame Sensor Modules consist of a breakout board, on which a SMD flame sensor is mounted, ideal for easy evaluation and quick prototype development. A ribbon cable for flexible connection to user’s hardware or backplane and control board is included.

Part Number

Including Sensor


Filter BW Use
USEQFSM122L100 USEQFSEA22L180 2.20 μm Long pass Broadband flame detection
USEQFSM150L100 USEQFSEA50L180 5.00 μm Long pass Human motion rejection
USEQFSM1391100 USEQFSEA391180 3.91 μm 90 nm Rejection channel
USEQFSM1464100 USEQFSEA464180 4.64 μm 180 nm Flame channel (wide FoV)
USEQFSM1448100 USEQFSEA448180 4.48 μm 620 nm Flame channel (main detector)

Outfitted with all necessary components for the 1.8-3.6 V power supply of the device, all functionality of the sensor is routed out to a 10-pin 1.27mm pitch IDC connector on the back side of the 16 x 13.8 mm PCB. The build height including the socket is 9 mm. They provide up to 1 MHz Fast Mode+ I2C communication to configure the sensor and read data from it.

  Pin Symbol Type
1 Vsupply Power supply
2 Unassigned
3 SCL (I2C) Digital in/out
4 SDA (I2C) Digital in/out
5 CS Digital in
6 INT Digital out
7 SYNC Digital in/out
8 CLK Digital in/out
9 Unassigned
10 GND Ground

There is a chip select/enable pin and an interrupt output available. The CLK/SYNC pins can be used to feed an external clock signal in to the board or, alternatively, distribute the clock signal of one board to several other boards, thereby creating a synchronized “network” of sensors.

Part Number Use Type
USEQCSK0000000 Control board for modules
  • Preassembled backplane PCB
  • USB communications cable
  • Ribbon cable, optional use (up to 4)

USEQCSK0000000 can flexibly host up to four modules. With no hardware design work required, a combination of this backplane board and any of the attached SMD sensors can produce infrared sensor signal measurements out of the box in the early evaluation and design stages. This control board is provided with PC software allowing the user to configure and read out each of the SMD sensors connected. The sensor data is visualised in real time on a scope plot in the user interface. A csv file capture facility records the digital signals from the sensors for further processing by the user.

QFC Analog TO39 Sensor

QFC Analog TO39 Sensor

KEMET’s QFC pyroelectric flame sensors provide accurate discrimination of flame sources in triple IR flame detection systems, through their excellent signal to noise characteristic at the signature 8 – 10 Hz flicker range of a flame. The sensor element is built into a low noise circuit that has an internal CMOS op amp with a 10 GΩ feedback resistor outputting a voltage signal centered around half the supply rail. Exceptionally high responsivity, a wide field of view and rapid recovery from thermal and electrical shocks makes it the ideal solution for demanding flame detection applications.


  Part Number Filter Cut On Wavelength Cut Off Wavelength
USEQFCSA338100 3.38 μm bandpass 3.295 μm typical 3.475 μm typical
USEQFCSA391100 3.91 μm bandpass 3.865 μm typical 3.955 μm typical
USEQFCSA435100 4.35 μm bandpass 4.05 μm typical 4.65 μm typical
USEQFCSA448100 4.48 μm bandpass 4.17 μm typical 4.79 μm typical
USEQFCSA455100 4.55 μm bandpass 4.34 μm typical 4.76 μm typical
USEQFCSA500100 5.00 μm cut on 5.0 μm typical
USEQFCSA550100 5.50 μm cut on 5.5 μm typical
Features and Benefits Applications for Rapid Fire Detection
  • Exceptionally high responsivity
  • Wide field of view angle, typically 100°
  • Rapid recovery from thermal and electrical shock, <1 second downtime
  • TO39 package
  • Analog output
  • Integrated operational amplifier
  • Industrial
  • General manufacturing
  • Chemical production
  • Oil and gas
  • Marine, transportation, and logistics
  • Energy and power
  • Healthcare
  • Infrastructure protection
  • Forest protection
Field of View



Product Listing

Product Listing

Loading your content...
Loading your content...
QFS/QFC Evaluation Kit

QFS/QFC Evaluation Kit

To allow for further in-depth testing of these flame sensing and detection solutions, KEMET is proposing 2 evaluation kits, a digital one and an analog one. The purpose of these kits is to enable engineers and technicians to carry out simple and effective evaluation of KEMET flame sensors, experiment with the sample flame detection ratio based algorithm, and to capture measured data to a PC through the KEMET Flame Sensing Evaluation Tool software.

  Part Number Use Includes
USEQFSK1000000 SMD Flame Sensing Evaluation Kit
  • USEQFS prototype flame sensing detector
  • 4 sensors
    • USEQFSEA50L180 1p x 5.0 µm LWP
    • USEQFSEA391180 1p x 3.91 µm/90 nm
    • USEQFSEA464180 1p x 4.64 µm/180 nm
    • USEQFSEA448180 1p x 4.48 µm/620 nm
  • USB communications cable
  Part Number Use Includes
USEQFCK4000000 TO Flame Sensing Evaluation Kit
  • Flame detection demonstrator kit
  • 3 sensors
    • USEQFCSA391100 3.91 μm bandpass filter
    • USEQFCSA435100 4.35 μm bandpass filter
    • USEQFCSA500100 5.00 μm cut on filter
  • 9 VDC power supply
  • USB communications cable