Aquaboy Deluxe 2019 Voltage issues

[strat68]

I'm getting low voltage issues at most points.  The leds blink fine.  With the input of a signal generator I can hear some affect on the signal.

For example:

On pin 2 of the LT1054 charge pump it reads 2.78 when it's supposed to get 5.  Pin 8 shows 8.28 when the expected value is 9.26.

On both MN3005s  all pine are reading 50-60% of expected values.  Same with the TL072.

Is this simply a wrong resisted early in the power circuit or something more complicated?
Thanks

[madbean]

Pin8 is going to have some variance depending on your power supply. For example, I use the same One Spot supply for every single project documentation I do. It outputs 9.4V nominal and 9.24V after a 1n5817 polarity protection diode. So, getting a different value there is completely dependent on your power supply specs. The thing to look at is if you are getting about 15v or so out of the regulator. If not, something has gone wrong and there are steps we can take to try and pinpoint the error.

[strat68]

Thanks for the quick reply.  The voltages coming out of the regulator are 12.87, 0 , 10.78.

[strat68]

bump

[madbean]

Something is going wrong with that supply voltage. Either the charge pump isn't doing its job or an IC is pulling too much current.

I'd start by pulling all the ICs except the charge pump. Now measure the voltages on the regulator again and see if you are getting closer to 18, 0, 15. If not, then the problem may just be with the charge pump.

If you do get the right voltages with all other ICs removed, then start inserting each IC in order, one by one. After inserting an IC check the voltage regulator again. That will help you determine which IC is pulling too much current and where we should focus on.

[strat68]

Thanks!  I haven't checked for a response in a while. 

[strat68]

The problem were the MN3005's.  They both dropped the voltage,  I has 2 spares and they fixed the voltage issue.  I started the calibration the first check on pin7 of IC3 failed.  No sound just a hiss.  Nor did pin7 of IC2  have any sound.  I'll just have to trace the circuit to see where the sound dies.  The TL062 and 072 both have sound.
Thanks for the help.