TP213 -2.3V
TP211 -1.67V
TP207 -0.44V
That does not compute. Can you recheck those three? Value at TP207 seems wrong.
And while at it, check voltages at TP205, TP206, TP208
OK TP207 was wrong its +0.44V
Rechecked the Resistor network as well
R238
pin 1 = -43.3mV
pin 2 = -0.438V
pin 3 = -0.833V
pin 4 = -0.833V
pin 5 = -0.395V
pin 6 = +43.3mV
OP AMP out -1.2V
TP214 -2.3V
TP213 -0.4V (corrected)
TP212 +0.4V
TP211 -1.6V
TP210 +10.3V
TP209 +10.2V
TP205 +9.4V
TP207 +0.44V
TP230 -13.9V
TP231 -0.833V
While messing with the unit I set it to current mode and complacence voltage to 2.100V and the meter measured 2.10018V I checked the output and it was right no the money (2.10018V measure with Keithley 2700). The current was set to 10ma but the DAC must be dead as it always Measures 43mV on NIDAC . Current reading on the meter is 0.833mA and the output stage is not outputting any current at least based on the measurement across R562 R563 being 0.000mV
Tried it with Compliance Voltage of 21.0v and that works as well.
But current is always reading 0.833mA same as pins 2, 3 off R238. So the current feedback must be trying to correct for its reading.
U227 feeds directly to the pin IFB which I think is Current Feedback.
And this is the issues there is a large voltage on the indeed of this chip. The chip is a AMP03G which makes sense.
Now to figure out where this voltage difference is coming from there is a ton of switching going on in this area.
In voltage mode i get -240V all the time even when output is off. So something is working.
Updated firmware from version C11 to C32 while i was inside. Used images from Xdevs and TL866II plus programmer.
The memory was TMS28F020 and I saved C11 just in case.
So the measurement side is working and the output side is working .
NV dac still crazy hot probably needs to be changed - but outputting correct values.