East Tester ET4410&ET4510 Desktop LCR Meter

[Martin72]

Last for today was to identify the chips on the main pcb.
Controller is a STM32F103RC, "lots" of CD74HC4053/4051, several analog switches (SGM3002/3003), highspeed rail to rail op-amp (MS8052), TL072C and OPA2354.
Also a couple of 5-pin ICs, I can´t identify at the moment.
I´ve asked East Tester for a schematic today - I know, chances are near zero, but it will be total zero if I won´t ask for it. 
There are several testpoints on the main pcb, most of them are for the voltages, but there are four others:
-Vmea (Vmeasure I guess)
-SigOut (signal out, very close to the output)
-DCA1out (??)
-Vcur (??)

I took a 1µF cap and measure it with 1khz and 1V, meanwhile I pick up the testpoints with scope against ground, see below.
Next steps are measure the caps from work and compare to the three other LCRs, two of tem are calibrated.
Then searching for different inductors..
And so on, if there are questions about what I should test or general things concerning the ET4410, feel free to ask.
Actually I can say, it´s a very good instrument for the money 
But it says also, that the DE5000 is an excellent intrument for its money...

[precaud]

can the meter be calibrated by the user? Or it has to be sent back to them?

Hi Franco,
A little bit OT, but if your concern is about accuracy on the lowest range, all of the 4-wire LCR/impedance meters I have or have serviced (mostly HP 427x and 428x) have no actual adjustment for it. Calibration of that range is really just 'verification'. Accuracy depends entirely on the Open/Short (or Open/Short/Load) math to bring it into spec. And to some extent, the integrity of the test fixture.

[SHTechnics]

Anyone who has an idea if it is possible to 'upgrade' an ET4401 to an ET4410?

[Martin72]

Hi,

If the hardware is the same, maybe a readout of the cpus can be the solution, but I´m not a software crack.
Looking at my main pcb, it´s named by ET-44, without explicit 01, 02 or 10.

Today I wanted to continue testing, everything was ready - but some visitors came today, so next weekend....
Interesting: The fixture for our sourcetronic LCR fits also on my ET4410...
Next time I want to talk about the handling in general and some of the functions.
For example, what I don´t like is the missing of a manual range selection - Only "lock"...
To be continued.

[SHTechnics]

So it could be only a difference in firmware?

[Martin72]

When we compare the hardware of the 4401 and 4410 and didn´t find any difference, it MUST be a difference in the software.

Martin

[Kleinstein]

The video teardown (defporn)  of the 4401 and the pictures of the 4410 look quite different (the newer PCB has less relais and the connector directly at the PCB).  However both boards show ET44.  and just different versions / dates.

[Martin72]

So SHTechnics "must" post pics from his ET4401 to make it finally clear.

[Martin72]

It´s totally different and the CPU is "masked" in defpoms video...
Maybe a real early version.

[SmokedComponent]

I just received mine. I can confirm that the FREG button hasn't been fixed.   
Other than that, looks good so far after some basic tests; will do some more later.

[SHTechnics]

Martin72; I just saw your response today, I'll include some pics I've made of the ET4401

[Martin72]

Hi,

Did you masked all the IC´s ??

[SHTechnics]

Hi,

Did you masked all the IC´s ??

No, I didn't. It was like that when I opened it.

[Martin72]

Interesting, mine looks "bare"..
Nevertheless,iIt seems the pcb´s are identical.

[SHTechnics]

Interesting, mine looks "bare"..
Nevertheless,iIt seems the pcb´s are identical.

Hmm, when they are identical it could be that the firmware is maybe the only difference.
10 kHz is more than sufficient but it would be nice to 'tweak' it to 100kHz 

[Martin72]

When you could upload pics with higher resolution, I could take a close look.
PCB version number are the same, but it could have different cap or resistance values.

[Kleinstein]

In the pictures one can not identify many OPs, but the one readable one (OPA2354) is pretty fast with 250 MHz GBW.
Many of the other chips are 4051 CMOS switches.
The slower version may also use slower OPs and possibly even a lower memory µC.

[SHTechnics]

When you could upload pics with higher resolution, I could take a close look.
PCB version number are the same, but it could have different cap or resistance values.

I'll do that this week. At the same time I'll check out which IC's are masked with your pics as reference.
Btw: ever seen the firmware of an ET44xx available for download?

[SHTechnics]

Where did you find the OPA2354's? I'll check for them on my version.

[Kleinstein]

Where did you find the OPA2354's? I'll check for them on my version.

The OPA2354 I found is U301, at the right edge of the board.

edit: It is not such an expensive chip ( ~$3-$4 in QTy 1)  , so one may still find it in the cheaper versions.

[SHTechnics]

Thanks, the reason I asked is because almost every IC and mosfet is blank 

[Martin72]

FYI, what the IC names concerns:

Last for today was to identify the chips on the main pcb.
Controller is a STM32F103RC, "lots" of CD74HC4053/4051, several analog switches (SGM3002/3003), highspeed rail to rail op-amp (MS8052), TL072C and OPA2354.
Also a couple of 5-pin ICs, I can´t identify at the moment.

[SHTechnics]

I revealed most IC's but U301 stays a mystery because it's etched too deep. Strange that they did this, but I suspect it's exactly the same hardware as the 4402 and 4410 (U301 is possibly an OPA2354) so they've masked them on the 4401.

[Martin72]

Hi,

It´s a OPA2354...
The pic below you can download it and zoom in..
When it´s interesting, I can make new pics from the pcb, using a camera stand and better light.

Martin

[SHTechnics]

I believe it's indeed a OPA2354 but I can't be sure because mine is an ET4401 and not a 4410. 'Maybe' it's different although I think it's all the same except the firmware.

Any clue about firmware or anyone who has flashed new firmware?