IGBT selector and Current v. Frequency tool Energy Saving Products BU July 2013 COMPANY CONFIDENTIAL 25 The traditional selector Selection based on IGBT parameters (Vce, Vbr, Ic, etc) COMPANY CONFIDENTIAL 26 A selector tool based on applications parameters http://igbttool.irf.com/ Related topics Article on tool To select a part You know the part numbers and want the Current v. Frequency curves Explanation of selection criteria English, Chinese, Japanese Questions and comments COMPANY CONFIDENTIAL 27 The two tools are open to anybody – no sign-in To select a part COMPANY CONFIDENTIAL 28 To select a part enter the operating conditions First: chose an application Multi-select Operating voltage, rated voltage range and short-circuit Thermal operating conditions “per IGBT”: heatsink for 6 IGBTs would be 0.3 COMPANY CONFIDENTIAL 29 A short list of suitable parts They are ranked by junction temperature Click on the part number for data sheet. Hover on the part number for basic details. Check the boxes for the Current v. Frequency curves. Or you can change the application parameters and proceed to a new selection Try changing the shortcircuit requirement. Check the difference in conduction losses COMPANY CONFIDENTIAL 30 Current v. Frequency plots for parts selected Curve for each IGBT is at Tjmax less the specified derating. Export to pdf Criteria for calculations of losses are described below the curves COMPANY CONFIDENTIAL 31 Plots for parts you already know You can access this page directly from the front page. How many IGBTs do you want to compare? (max of 5) Chose an application Select the parts you want to compare Select the conditions Click on the button at the bottom of the page COMPANY CONFIDENTIAL 32 Go directly into the Current v. Frequency tool If you know the part numbers to compare you can go directly into the Current v. Frequency tool from the front page COMPANY CONFIDENTIAL 33 Plots for parts you already know Select the parts you want to compare Select the conditions Click on the button at the bottom of the page How many IGBTs do you want to compare? (max of 5) Chose an application COMPANY CONFIDENTIAL 34 Select an IGBT for a refrigerator compressor Motor drives need copacks Choose a mounting method and package: Short-circuit is required in motor drives IGBTs with higher s-c rating have higher conduction losses Operating voltage, rated voltage range Current and frequency Silicone pad Small sink or individual clips COMPANY CONFIDENTIAL 35 Four IGBTs meet the requirements Click for data sheet Lower losses, lower junction temperature Check the parts you want to compare for current v. frequency Switching and conduction losses Lowest losses Highest losses Losses are low. Can be done with surface-mounted IGBT without a heatsink (cheaper). Let’s try. COMPANY CONFIDENTIAL 36 A surface-mounted solution Surface mounting Chose d-paks (smaller and less expensive) 2oz PCB with vias COMPANY CONFIDENTIAL 37 One IGBT meets the requirements Power losses are close to those of TO-220 PCB is smaller and IGBTs are less expensive Vias can be eliminated by going to an D2-pak. Losses are the same but thermal resistance is lower Just enter D2-pak in the package selection COMPANY CONFIDENTIAL 38 What happens if we reduce the short-circuit time? The inverter in a refrigerator is mounted with the compressor. Risk of short-circuit is very low. We can reduce the short-circuit requirement from 10µs to 5µs, well within the response time of current-sensing ICs The tool returns the previous IGBT, plus a second one, the most efficient (trench design) Check the boxes for current v. frequency chart COMPANY CONFIDENTIAL 39 A closer look at the two IGBTs From this chart it appears that the IRGR4045D is capable of more current, particularly at lower frequencies. COMPANY CONFIDENTIAL 40 Select an IGBT for 500W PFC (cont. current) PFCs don’t need copacks TO-247 has better thermal characteristics Short-circuit is not required in a PFC Operating voltage, rated voltage range 100 kHz, 1.5A input rms Silicone pad Increase temperature derating for more safety Heatsink thermal resistance COMPANY CONFIDENTIAL 41 Several IGBTs meet the requirements Compare four IGBTs Losses are low, mostly switching A reminder: Losses are calculated for operation at 50% duty cycle. A boost converter normally operates at less than 50%. Hence conduction losses may be overstated. For this reason we have chosen the four IGBTs with best performance at high frequency: the “U” and the “W”. Another reminder: this is a selection tool, not a design tool COMPANY CONFIDENTIAL 42 Not much difference between the four IGBTs Price and availability may be the deciding factor in this application. The IRGPC40W is probably the most cost-effective choice. Notice: At 50% duty cycle, continuous current, Boost and Buck have same losses COMPANY CONFIDENTIAL 43 What if you don’t know the heatsink size? Select “Fixed case temperature” Enter a reasonable operating temperature for the stated conditions. A lower temperatures requires a bigger heatsink For SM applications remember that FR4 is limited to 110-125ºC The losses in the table can be used to calculate a first approximation for the heatsink thermal resistance Rth Now you can enter the thermal resistance of the heatsink and do a finer selection with a second (and third) iteration COMPANY CONFIDENTIAL 44 In summary This tool narrows down the list of potential candidates from hundreds to a few. It allows you to change operating conditions to match the design to the IGBT and reduce overall BOM cost (components + heatsink + PCB). It is not a design tool. It’s a selector tool Comparisons and losses are accurate only for the specific topology of this tool (Buck/Boost at 50% duty cycle). For design tools, go to our webpage COMPANY CONFIDENTIAL 45