What is a quick and effective way to identify defects on a circuit board assembly without conventional troubleshooting? The answer is thermography. Thermal infrared (IR) imaging devices are excellent tools for increasing the life expectancy of devices by getting real-time imagery of temperature distribution as well as development of heat on objects in a board through a contact-less tool.
Nip it in the bud
Higher-resolution thermal imaging cameras can spot overheating in individual components like transistors and resistors across the whole printed circuit board (PCB). This means that engineers can use it in an early-stage design to sort out circuitry damages. For example, a component that is not designed to go above 85°C could end up above 110°C and get stressed by overheating. The thermal camera immediately catches the over-heated component in its viewfinder without the engineer having to probe each component individually. This means that chances for an over-cooked component to ruin a PCB are far lesser since the engineer can see almost the entire board at a glance.
Earlier this year, Keysight had announced higher-temperature models, targeting electrical and electronic applications where these can be used to detect variations over a wider temperature range. U5856A and U5857A can perform temperature measurements up to 650°C and 1200°C, respectively.
Fluke and FLIR also launched similarly-named models: Fluke’s TiX1000 and FLIR’s T1K or T1020. Both these models have very good specifications; details of these have been included in the table.
Upgrades for displays and sensors
Fluke’s new expert series thermal imagers called TiX560 and TiX520 come with an articulating lens that can rotate 180° as well as a large touchscreen LCD featuring a resolution of 320×240. The camera also comes with on-camera analytics and features SuperResolution mode that quadruples the resolution into 640×480 or even 1024×768, which is full HD (FHD).
FLIR has come out with a thermal imager (T1K) that comes with a sensor having a 1024×768 HD detector and features up to 3.1 megapixels of detection with its UltraMax processing technology. It also comes with HDIR lenses that claim to deliver more accurate measurements from a greater distance. (FLIR claims twice the distance as legacy systems.) Additionally, it features video recording along with continuous auto-focus. FLIR also packs in some software tools that allow users to analyse data, change colour patterns and generate detailed reports.
Keysight U5850 series is also claimed to be among the first to come with four times in-camera fine resolution of 320×240 pixels from a 160×120 pixel detector that comes with manual-focus.
IR thermometer ILV-301 by Flex Instruments features a distance-to-spot ratio of 30:1 calculated at 95 per cent energy. It can sense a range from -30°C to 800°C.
MECO has a thermometer called IRT1050P that can sense from -50°C to 1050°C. It features a distance-to-spot ratio of 50:1, too.
Flex Instruments’ thermal camera (model number TG-501) features a 128×128 pixel thermal image after interpolation. Its display is a 160×128 pixel TFT-LCD, mounted on a pistol grip with one navigator key operation.
Making it easier to use thermal cameras
FLIR TG165 was announced late last year, which is an easy-to-use thermal imager built for do-it-yourself users and for industrial professionals who require a compact low-cost tool for quick troubleshooting.
Last year, Fluke talked about its introduction of a laser focus system in thermal imagers where a laser beam was used to measure the distance, which aids the user to focus properly on the object.
FLIR TG165 comes with dual rotating lasers to visually mark the size and location of what is being measured, while an on-screen crosshair pinpoints the region on the thermal image.
FLIR C2 was also launched last year as a pocket-size camera designed to show hidden heat patterns due to energy leaks, bad wiring, HVAC issues and other problems. FLIR’s T1K also comes with a rotating block that houses the optics so you can use it on tougher angles while holding your head in different positions when you are using the touchscreen to operate the device.
Start debugging those electronics
You can now pick up a thermal imager and start working on debugging your circuit board. It will help you find that one overheating chip in the board that is causing the embedded system to fail, or quickly identify that short in the circuit.