Spectra S1+ Breast pump - No suction

[caphair]

Re: Spectra S1+ Breast pump - No suction

Top of Q9 does not connect to Q7 or any other leads.

Top of R21 connects to the Source pins of Q7
R21 and R30 are in series and bottom of R30 is connected to the Gate of Q7

I’ve attached pics to show the operations of Q9-12 when powered on and off.

Seems like Q9 possibly cycling whatever’s plugged into connector SOL? Looks like maybe an actuator. But that’s the clicking I hear when powered on without suction pump.

[momaka]

Re: Spectra S1+ Breast pump - No suction

Top of Q9 does not connect to Q7 or any other leads.

Top of R21 connects to the Source pins of Q7
R21 and R30 are in series and bottom of R30 is connected to the Gate of Q7

Do any of the resistor leads of R21 or R30 connect to top pin of Q9? If not, what about Q11? I'm curious what drives Q7.

I've attached pics to show the operations of Q9-12 when powered on and off.

Seems like Q9 possibly cycling whatever's plugged into connector SOL? Looks like maybe an actuator. But that's the clicking I hear when powered on without suction pump.

Hmm. So the 0-4V fluctuation is consistent with the clicking?
Can you trace where the Emitter/Source pin of Q11 goes to? (Should be pin 3, the one on the right when the SOT-23 device is viewed with the single pin at the top, and two at the bottom.)

[caphair]

Re: Spectra S1+ Breast pump - No suction

R21 and R30 do not connect to the top pins of Q9 or Q11.

The 0-4v fluctuation is consistent with the clicking, as well as small fluctuations with the main power ~11-8-11.5v

Pin 3 of Q11 goes up to the drain pins of Q2 (top right of the board) which happens to be the same ic as Q7.

[redwire]

Re: Spectra S1+ Breast pump - No suction

These parts would have resistors inside:
Q9, Q12 SOT-23 marking NF, NPN digital transistor KRC106S or DRC2124X
Q11 SOT-23 marking PF, PNP digital transistor KRA106S

Q8 SOT-23 marking AO7? likely N-ch mosfet driving the solenoid.

My take on the pcb board:
Q9 drives Q7 for the motor.
Q12 drives Q11 for... braking?
Q10 drives Q8 for the solenoid.

It seems to have motor current-sense R32/R45 back to the MCU.

[caphair]

Re: Spectra S1+ Breast pump - No suction

These parts would have resistors inside:
Q9, Q12 SOT-23 marking NF, NPN digital transistor KRC106S or DRC2124X
Q11 SOT-23 marking PF, PNP digital transistor KRA106S

Q8 SOT-23 marking AO7? likely N-ch mosfet driving the solenoid.

My take on the pcb board:
Q9 drives Q7 for the motor.
Q12 drives Q11 for... braking?
Q10 drives Q8 for the solenoid.

It seems to have motor current-sense R32/R45 back to the MCU.

So would Q9 be the suspect for the motor not turning on?

[caphair]

Re: Spectra S1+ Breast pump - No suction

I’m now wondering if Q9 does drive Q7 if there’s maybe a break to Q9 to Q7 gate within the PCB. I measure 57Mohm from those two points.

Also my meter has a duty cycle option that I probed the bottom left pin of Q9 (base?) and can see duty percentage change as I change the speed of the vacuum motor through the up/down controls

Bottom right pin of Q9 connects to ground so maybe it’s supposed to be grounding the voltage of Q7 gate to turn the motor on?

[redwire]

Re: Spectra S1+ Breast pump - No suction

This is how the circuit looks to me. To turn on the pump motor, Q9-C should go to ground. You could try tap a 1k resistor to GND and see if the mosfet Q7 turns on.

[caphair]

Re: Spectra S1+ Breast pump - No suction

This is how the circuit looks to me. To turn on the pump motor, Q9-C should go to ground. You could try tap a 1k resistor to GND and see if the mosfet Q7 turns on.

Tap it to G of Q7?

What's the role of R30? Isn't it a 200 ohm? Labeled “201”

[redwire]

Re: Spectra S1+ Breast pump - No suction

I would tap a 1k resistor between GND and Q9-C which should drop Q7 gate voltage so it turns on.
R30 is to slow down the mosfet switching a little bit. It could be 200R.

[caphair]

Re: Spectra S1+ Breast pump - No suction

I would tap a 1k resistor between GND and Q9-C which should drop Q7 gate voltage so it turns on.
R30 is to slow down the mosfet switching a little bit. It could be 200R.

Pump did not turn on but I suspect that's because there's no voltage on Q9-C which is why I was suspecting a break within the Pcb possibly.

I tried jumping Q9-C to R30 and heard a whining noise measuring voltage at pump connector saw oscillating 0-2v. Possibly because 1k was too high dropping the voltage?

Didn't want to just try jumping from Q9-C directly to R30 without first reporting back and seeing if that would be a good idea or if I could damage something

[caphair]

Re: Spectra S1+ Breast pump - No suction

So out of curiousity I wondered if the trace from Q9-C to R30 was on the backside of the board. I had to remove one of the push buttons and there it was, corroded.

Cleaned it up but the trace going to R30 was too far gone. Ended up soldering a jumper wire and it's back to life!

Thanks everyone for your help on this one. Wouldn't have thought to look there without going through how it's configured.

[redwire]

Re: Spectra S1+ Breast pump - No suction

so that's where the water went! Glad it's fixed, we don't want any starving babies

[momaka]

Re: Spectra S1+ Breast pump - No suction

Nice job finding the fault fellas! Glad to see another repair success story.

[sam_sam_sam]

Re: Spectra S1+ Breast pump - No suction

One more repair that took some doing

[caphair]

Re: Spectra S1+ Breast pump - No suction

Question about the jumper wire I used, it had a clear tube inside the insulation that the copper wire wraps around. Not sure what it came from, but curious what application something like this would be used for?

[momaka]

Re: Spectra S1+ Breast pump - No suction

Was there a thin wire inside the thin clear tube as well? If so, this might be some kind of shielded wire. Or it could also be that the clear tube inside was for reinforcement... though I'm leaning more towards shielded wire.

[caphair]

Re: Spectra S1+ Breast pump - No suction

Actually don’t think there was a thin wire inside the tubing. Just a flat looking copper wire that wrapped around it. The copper looked wider than normal strand

[stj]

Re: Spectra S1+ Breast pump - No suction

extra flexible wire - used in places where it will bend - like in robots.
i used to have similar but older wire where the copper was wrapped around a thick cotton cord.

btw, i still think it's a huge waste of technology just to replace a hand!

[caphair]

Re: Spectra S1+ Breast pump - No suction

extra flexible wire - used in places where it will bend - like in robots.
i used to have similar but older wire where the copper was wrapped around a thick cotton cord.

btw, i still think it's a huge waste of technology just to replace a hand!

😂😂 agreed. Saw that these go for around $200. Pretty crazy to me

[momaka]

Re: Spectra S1+ Breast pump - No suction

btw, i still think it's a huge waste of technology just to replace a hand!

What isn't today? They are putting "smart" MCUs in everything.
Also, haven't you seen Demolition Man, the movie? With the way things are headed with VR and smart technology... and now with covid-19 measures restricting/limiting how people meet and interact, I suspect it won't be long before we'll be using the three shells instead of toilet paper (remember the TP shortage?) and have sex through VR only. LOL!