Jan, I have one LCD module very similar to the BOM unit but positive type. I would like to use it in autoranger since I happened to have no other use for it. Do you know if it will work as is? I have no intention to modify or tweak the autoranger to use it, only if it works right away.
One more question. Do I understand it right that the pinhead connectors only carry control signals?
Regards,
Oleg
One more question. Do I understand it right that the pinhead connectors only carry control signals?
Regards,
Oleg
Oleg, the software should be able to run with this class of displays, same connections, with a compatible display controller. The specified display has an ST7066U controller which should be compatible to the well-know HD44780 from Hitachi.
But you should try fist before soldering it together. I tried to get an OLED display going, presumably compatible, but no luck.
The flatcable carries static control signals, the 5V supply and the DC RMS voltage from the AD536. No signal.
Jan
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You could solder the row of pins on the top of the board, then slip the display over it and put some bending pressure on it so all pins make contact. Then see if you get sensible display. You probably need an extra hand for it...
Note that if you have a dark display you may need to adjust the contrast trimpot!
Jan
For people interested, this is the cable I am ordering with the connectors (DigiKey MC14G-5-ND).
Electronic Components and Parts Search | DigiKey Electronics
C27 on the PCB a 3pin device, all other cer-caps are also 3pin and have the middle pin connected with an outside pin, this connection seems to be missing at C27, as the circuit connections to C27 are on the outside pins, when a small C is fitted in this spot you need to bend the legs in such a way that the outside holes on the PCB are used (as the center pin seems to be unconnected).
Am I making sense?
Am I making sense?
Yes you make sense - it is in the data package, I think on the layout guide. For C27, for some reason, the connection between the 2 pin-1's is not present on the PCB, so for C27 you need to use a 5mm/0.2inch pitch part and use the two outer holes, or if you use a smaller (like I did) spread the wires a bit.
In hindsight, it would have been better just to use a 2-pin footprint and specify a specific part, but I always try to be flexible...
Jan
Part value change
Those of you who are progressing to the calibration section may have found that the -32dB adjustment in Bal mode cannot reach the required value. The reason for this is that the value of C6 at 510pF is incorrect. It should be 360pF.
The counterpart of C6 is C10 and that is correct at 510pF.
For some reason the C10 value ended up as the C6 value as well in the BOM, sorry about that.
I will amend the relevant files in the Data Pack later today. A suitable 360pF cap from Mouser is 80-C322C361JDG; it is a 5% part although I would prefer a 2% tol part. But any COG or NPO that fits the board will do. If you have a couple 180pF laying around, that will of course work fine in parallel.
Jan
Those of you who are progressing to the calibration section may have found that the -32dB adjustment in Bal mode cannot reach the required value. The reason for this is that the value of C6 at 510pF is incorrect. It should be 360pF.
The counterpart of C6 is C10 and that is correct at 510pF.
For some reason the C10 value ended up as the C6 value as well in the BOM, sorry about that.
I will amend the relevant files in the Data Pack later today. A suitable 360pF cap from Mouser is 80-C322C361JDG; it is a 5% part although I would prefer a 2% tol part. But any COG or NPO that fits the board will do. If you have a couple 180pF laying around, that will of course work fine in parallel.
Jan
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Oleg, yes indeed. You were also right about C1, C8 being part of the atten board, not the control board.
All corrected, thanks for the heads-up.
Jan