Damaged Silicon Identification - Inverter repair - SUCCESS ! - Page 1
Forum section: electronics / repair

author: Dunk_c
author_rank: Contributor
timestamp: June 21, 2023, 12:00:22 am
content: HiI have a blown component on an Aero-sharp inverter that I cannot identify.No luck finding a circuit diagram or service manual on line for HR-INV-X01-015The inverter is not showing any fault indicators and the unit appears to be OK except that there is no Pout. In the previous week there was a humming/rattling noise from inside the cabinet that ceased when I did a restart.I think the smoked component maybe a MOSFET to control the output relays and would like to try repairing the board. The underlying tracks are still all connected.Hopefully someone can identify it?Cheers

author: fzabkar
author_rank: Super Contributor
timestamp: June 21, 2023, 06:14:40 am
content: The bottom line is the part number.This part appears to match the pinout, but it would be one of many possibilities:https://www.infineon.com/dgdl/Infineon-IRF7103-DataSheet-v01_01-EN.pdf?fileId=5546d462533600a4015355f0f0141ac6

author: gamalot
author_rank: Super Contributor
timestamp: June 21, 2023, 07:09:37 am
content: Quote from: fzabkar on June 21, 2023, 06:14:40 am

author: mengfei
author_rank: Regular Contributor
timestamp: June 21, 2023, 07:44:25 am
content: it looks like the PN starts with 7**3 but in the website there are a few combinations of those PN, you could get the highest spec or use the link belowIf you know what you needhttps://www.infineon.com/cms/en/design-support/finder-selection-tools/product-finder/mosfet-finder/?redirId=143927

author: wraper
author_rank: Unknown
timestamp: June 21, 2023, 08:00:51 am
content: You need to remove all carbonized PCB material, then bodge a new part on wires and fix it with neutral RTV silicone or UV solder resist. Carbonized FR-4 becomes electrically conductive, so you should never leave burned PCB material unless it's totally isolated to one trace only.

author: Dunk_c
author_rank: Contributor
timestamp: June 21, 2023, 09:33:53 am
content: Thanksi did not know that. I was going to apply conformal coating obver the damaged areas after masking off the solder pads and putting the new part in the same place but the carbonized PCB would have still been there. Some more advice here would be good please. Sounds like you might mean cutting the tracks back to clean PCB and using jumpers?

author: Dunk_c
author_rank: Contributor
timestamp: June 21, 2023, 09:40:23 am
content: Thanks the F7103 looks like a possibly the most likely match

author: Dunk_c
author_rank: Contributor
timestamp: June 21, 2023, 09:42:27 am
content: Thanks for the lead. That may well be it 👍

author: Dunk_c
author_rank: Contributor
timestamp: June 21, 2023, 09:52:01 am
content: A quick search for a Dual N-Channel MOSFET, 3 A, 50 V, 8-Pin SOIC Infineon IRF7103PBF shows that RS Components in Taiwan has them but not Australia. I still have to look at the spec sheet for the highest rated version but in the meantime can anyone suggest a source?Thanks

author: gamalot
author_rank: Super Contributor
timestamp: June 21, 2023, 01:47:26 pm
content: You can buy IRF7103TRPBF, they are packaged in a tape reel instead of a tube.

author: Dunk_c
author_rank: Contributor
timestamp: June 21, 2023, 09:31:15 pm
content: Thanks EveryoneElement14 Australia had IRF7103TRPBF in stock same day dispatch.

author: Dunk_c
author_rank: Contributor
timestamp: June 22, 2023, 06:22:38 am
content: One more thing …I forgot to photograph PCB before removing the chip 😩How do I ensure correct orientation of the IC on the PCB? The datasheet has no typical circuit diagram but there appears to be a notch on the PCB screen print.

author: gamalot
author_rank: Super Contributor
timestamp: June 22, 2023, 06:40:52 am
content: In your pictures, the bottom left pin is the pin 1.

author: ArdWar
author_rank: Frequent Contributor
timestamp: June 22, 2023, 06:41:59 am
content: Pin 1 is bottom left in your photo. There's silkscreen visible, the traces also matches with the double drain pins.Your MOSFET should have matching dot or bevel.

author: Dunk_c
author_rank: Contributor
timestamp: June 22, 2023, 06:49:09 am
content: Thanks for the confirmation 🙏🙏🙏🙏🙏🙏🙏I reckon I have less that 50% chance of a successful repair but worth a go.Not worth buying a new (or second hand) isolated inverter for my old 1.5kw system. Locked into a high feed in tariff with this old system until 2028, so won’t be upgrading until after that.

author: Dunk_c
author_rank: Contributor
timestamp: July 01, 2023, 11:58:25 pm
content: Well, I think I got lucky!Inverter back up and running and saved it from the skip!First IC was installed with a solder bridge I could not remove. When I removed that IC, solder had crept underneath also so luckily I replaced it. Used a finer tip in the iron second go.Also noticed a slight swollen 470uf 25V cap on the board (marked). Removed it and it had failed (180uf). Possibly this contributed to the MOSFET failure if it was supplying its regulated power.Scavenged a replacement from a scrapped power supply.Origin Energy can start paying me again !Thanks for the support!I will add this to the previous Miele induction cooker repair (power MOSFETs, diodes and capacitor), and call it a good 12 month!😀

author: phred01
author_rank: Contributor
timestamp: August 18, 2025, 11:48:15 am
content: Hi fellow Aerosharp owners 15yrs ago after 3 replacements under warranty got a good one. However noticed error LED not on but no output generated. Open the unit and found a small cap can floating on the front panel. on close inspection found where the cap come from On the display board the tracks were blown away with internals of the cap covered the damaged area. Having a spare display board on hand replace the damaged one Turn the inverter on surprise surprise output was being generated...thought easy fix Checked a few days later output again was zero. On inspection of the new display this cap to had spewed it little heart out (3.3uf @ 50v). So seeing this post decided to remove the main control board and noticed most of caps were in a distressed state. Seeing this replaced all the caps even the ones that looked physically OK. If the others were distressed then the ones looked OK would be faulty in a short time too. Repaired the display board and the inverter is making power again Logged power generation for four days and the caps are fine

author: phred01
author_rank: Contributor
timestamp: August 23, 2025, 04:44:00 am
content: Hi Fellow Aerosharp ownersDone the right move by replacing all 470 uf 100 uf and 47 uf even if they visually looked unstressed. Did capacitance measurements so were low by 10% and a number measured zero. My conclusion after 10 yrs of service expect the capacitors to deteriorate. Repaired 2KW unit produces 1.6KW @ noon ...... late winter / early spring

author: phred01
author_rank: Contributor
timestamp: September 16, 2025, 09:57:46 am
content: More success fixed 2 more units1 unit was stuck on please wait message replaced all the minor caps on the main board ...... unit is making 1.8kw midday in September2nd unit intermittent system error replaced same caps this too has came good also produces 1.8kw @ midday3rd unit Originally tried to power up but dropped out when output was > 50w. after replacing the caps The main control board crashes with 2 red leds lighting up......basket case it's a boat anchor now.Thought about the components on the main board and noticed how small the the smp transformers are My conclusion is they are running @ a very high frequency so the caps have work cut out for them Aboutwhen Aerosharps were made Chinese small caps of a poor quality So even with 105C rating their life is curtailed because the higher internal resistance and high currents contributes self heating therefore getting hotter than normal. Low ESRcaps would been better choice. When Aerosharp when pear shape I did panic so bought a BNU as a spare..... no future warranty support. So could replace the installed inverter like for like withouthaving to have the system reinspected So my success is 4 out of 5