Brother printer, help to identify 510A GNC

[richnormand]

Hopefully this might be helpful to someone with the same issue:
TL;DR: Printer stopped working, need help to identify 510A GNC integrated circuit on board.
Model: Brother laser printer HL-L2360DW
Message: Print unable ZC


From the Brother trouble shooting website, and the web, the solution is to turn off the printer, wait and turn it on again. Apparently this message is due to dropouts or other issues with the powerline. Typical “have you tried to turn it off and then on again”

Noted the “off” button did not work either. Unplugged from the mains did not restore the printer. Some more web searches also implicated the power supply board.  Its output is 24V and within specs. There is also another section providing about 6-8V with high impedance and a significant AC ripple on it that is on all the time, irrespective of the printer being on or off. Most likely for when the printer is in deep sleep mode and waiting to be awaken from the network or WiFi. Traced and reversed engineered that circuit, no bad parts, linked to the main board  on the bottom connector in the photo (arrow).

Now looked at the “off” soft button issue. Traced that from the keypad pcb to the main board and followed the trace to a ribbon to the top connector on the main board, to an IC called 510A GNC (arrow in lower middle middle). I could measure the change of resistance when it was pressed and the voltage swing when the printer is powered up. So the non-working on/off button does signal the IC.

Then I followed the power supply voltages to the main board to the bottom connector (arrow). Note the two aluminium electrolytics. The one on the right has the +24V from the power supply. The one on the left has +5V from the always on standby supply. The circuit circled does regulation of the 5V and extract a nice 1Vpp square wave at the line frequency derived from the ripple.  The 5V is applied to the 510A IC, as well as the square wave. So the “print unable ZC” could be a zero crossing to synch some printer signal….

I used a blast of “super freeze” on the IC (bad contact perhaps) and it the printer turned on, as long as the power line was applied. If disconnected it would revert to power on with the same error message. For the next few tests I soaked a Q-tip swab with the freeze spray to cool only the chip and eliminate any adjacent component. It worked. I then removed the chip with my smd rework station, cleaned all the contacts and pads and reinstalled. Same issue, so it was not a bad contact, it’s the chip.

I was not able to find a suitable replacement for the 510A GNC (photo) . The few potential candidates all had the wrong packaging, number of pins , function, etc… So, what is it? House number? Any ideas out there? 
Would be sad to throw away a perfectly good laser printer to the dump because of the $1 chip and a lack of schematics to repair or do a work-around.

Cheers and thanks.

[amyk]

The closest match for the marking and package is the PTN5100A, but I do not think its function of a USB-C IC is correct.

There is a rather large service manual available, which might yield more clues.

[richnormand]

Many thanks for looking into it amyk.

I will scope the chip again and see if the pinout and signals make sense. Indeed I did notice the I2C lines going to the eeprom next to it. It does not seem to be related to the usb controller at the other end of the board but who knows.
I did find the service manual you mentioned but unfortunately there is only a partial block diagram and no schematics. Yours seem to have more pages than what I have. 

Give me a day to scope the signals to the chip and compare to the PTN5100A

Cheers and thanks.

[tsman]

From what you've described of the connections and what is shown in amyk's service manual, it is the "HYPNOS" chip on the wiring diagram. It talks to the main CPU via I2C and feeds it an AC zero crossing signal + reset. The same chip seems to be used on several Brother laser printers. The name Hypnos means sleep so whoever designed these boards decided to be cute with the naming.

My guess is that it is some kind of microcontroller so it might not be available off the shelf. You might be able to kludge something together to generate the reset + zero crossing signals the main CPU wants and bypass this HYPNOS chip entirely. The problem is the I2C interface though.

[richnormand]

Looks like it tsman.

I started to look at the signals on the chip and amyk is a most likely lead at this time compared to what I found.
Although the chip is labeled as a usb-c  it looks like a lot of functions it provides would/could/might be useful for the sleep mode monitoring and wake up functions here. i'll need to fully scope the pins in fault mode and working modes.

If the chip is used on other Brother printers I might be able to find a cheap donor board out there. A quick look at Digikey and Mouser list them as non stock with a 7 week leadtime. Another place has a 6000 piece minimum order

More to come.

 

[tsman]

It isn't a NXP PTN5100ABS. It doesn't match up with how it is wired on these printer controller boards and functionality is completely different.

[fzabkar]

Can you identify some of the other ICs on the PCB? Perhaps the designer chose ICs from the same manufacturer, or from the same country of manufacture. For example, Japanese designers seem to prefer Japanese IC makers.

[richnormand]

OK, thanks for the replies tsman and fzabkar.

1)
Scoped the various pins and it does not seem to be the same pinout (VDD wrong place, clock signals, grounded pins, etc...) No direct path to usb circuits.

2)
The other chips and smds are typically Toshiba, Etrontech, Realtek,ST.... All the smd codes resolved to pretty much their functionality as I traced the circuits. That is why I am a bit surprised this one does not seem to fit the pattern (of course it has to be the one that is dodgy...)
Better start looking for a replacement board or a donor board then.

3)
The dot on the chip is about 0.5mm (whole thing is about 4x4mm) but does this look like a logo or am I grasping at straws here?

[tsman]

The dot on the chip is about 0.5mm (whole thing is about 4x4mm) but does this look like a logo or am I grasping at straws here?

Doesn't look like a logo to me. It is the path the laser engraver took to etch that dot.

[amyk]

From what you've described of the connections and what is shown in amyk's service manual, it is the "HYPNOS" chip on the wiring diagram. It talks to the main CPU via I2C and feeds it an AC zero crossing signal + reset. The same chip seems to be used on several Brother laser printers. The name Hypnos means sleep so whoever designed these boards decided to be cute with the naming.

My guess is that it is some kind of microcontroller so it might not be available off the shelf. You might be able to kludge something together to generate the reset + zero crossing signals the main CPU wants and bypass this HYPNOS chip entirely. The problem is the I2C interface though.

I found another service manual (for the L5800) which shows that chip having a 32K crystal, so it probably also contains an RTC. The part numbering is somewhat reminiscent of the Renesas R5F10xxx but that could just be a coincidence, and the pin names (REVOUT0, REVOUT1, REVOUT2, ZC_IN) don't give any useful results.

[fzabkar]

Could "510" be a YWW date code?

[richnormand]

Could be, who knows. 510A GNC is all there is on it.
GNC does not bring any results either.
Unlike most of the other components on the board that have brand logos or known numbers and codes this one is the oddball.

Now looking for a donor board or replacement board that is not worth (priced) as much as a new printer.

Just trying my best to not feed the landfill needlessly.
Hopefully the "right to repair" trend will progress.

[richnormand]

Update.

Found a few places on the web that have the whole board. Pretty high priced but OK.

Fired a note to Brother for a replacement chip or replacement main board. No dice, they don't provide that service.

Printer is  only 3 years old, so my sympathy for the "right to repair" trend is growing.
Nothing like buying a product that it designed for the landfill in our society..... 

[KL27x]

^ It's called progress. If we could buy a cheap anything, and it last forever, we would not have enough tax revenue to feed our government workers and defense budget.... along with a sky high unemployment rate. The stock market would crash and we'd have millions of people with no retirement or health care.

I know a guy still using an inexpensive laser printer from the 80's. They've since learned how to make these things not last that long.

[tooki]

I know a guy still using an inexpensive laser printer from the 80's. They've since learned how to make these things not last that long.

Correction: we’ve since learned how to manufacture them for 1/100th the price.