FMC ADC 100M 14b 4cha - Hardware issueshttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues2022-03-21T08:55:35Zhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/11V5 - Add soldermask both sides near standoff2022-03-21T08:55:35ZErik van der BijV5 - Add soldermask both sides near standoffIn the corner near standoff B4 there is no soldermask on copper areas on
both sides of the board. The idea was that this should improve the
cooling in this area that gets hot because of the regulator in this
corner. However, as there is no soldermask, the solder for the
components is leaking out (see attached images) which can create
problems.
As the surface is so small anyway, we believe it is better to add the
soldermask.
- Add soldermask on both sides near the B4 standoff to improve
solderability.
### Files
* [IMG_1176.JPG](/uploads/985199534940fcc16f4837de812066ad/IMG_1176.JPG)
* [IMG_1180.JPG](/uploads/ef42e4d7f10e0f5552d0c5fbca300852/IMG_1180.JPG)V6.0Erik van der BijErik van der Bijhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/14V5 - Noise level channel 1 higher than others2022-03-04T14:19:39ZErik van der BijV5 - Noise level channel 1 higher than othersThe noise level of channel one is in the +/- 50mV range is around a
factor of 3 (~5dB) higher on channel 1 than on the other channels. This
is likely caused by this channel being closest to the DC/DC switched
power supply.
- Re-measure SNR and ENOB of all channels and document in spec on wiki
- Analyze noise sources (spikes) on all channels
- Consider moving all channels on the PCB design and having the
Trigger input closest to the DC/DC
- Consider better shielding/decoupling of the DC/DC converterV6.0Erik van der BijErik van der Bijhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/6V5 - T1,T2, BOM description is wrong2019-11-08T18:40:17ZErik van der BijV5 - T1,T2, BOM description is wrongThe BOM at
https://edms.cern.ch/ui/file/1165461/1/EDA-02063-V5-0_pcb-mat.pdf
reads:
T1,T2 2 **50V 200mA** N-Channel Enhancement Mode Field-Effect Transistor
BSH103 NXP SEMICONDUCTORS BSH103 SOT23-3
The description of **50V 200mA** is wrong.
The datasheet at
https://assets.nexperia.com/documents/data-sheet/BSH103.pdf (This NXP
part is moved to Nexperia)
shows **30V 0.85A**.
- Correct description of library item BSH103 to show 30V 0.85A instead
of 50V, 200mA.
- Change NXP SEMICONDUCTORS to Nexperia (see cover letter on the
datasheet)
*Problem found by Seven Solutions, during price enquiry for production.*V6.0Erik van der BijErik van der Bijhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/8V5 - Specify Phillips screws instead of Hexalobular type2019-11-08T18:38:57ZErik van der BijV5 - Specify Phillips screws instead of Hexalobular typeThe [mechanical
BOM](https://edms.cern.ch/file/1165461/1/EDA-02063-V5-0_arrangement-mat.pdf)
specifies "Hexalobular Pan Head Screws".
(BN 5687 ISO 14583 - Hexalobular Pan Head Screws - Fully Threaded -
Stainless Steel A2 M2.5 - L=6mm BOSSARD - 3061597)
However, the Xtech and ELMA FMC front-panel kits both contain Phillips
screws. Also it is more practical to use Phillips screws.
Improve BOM. Copy info from
[FMC\_Delay\_1ns\_4Cha](https://edms.cern.ch/file/1382769/1/EDA-02267-V6-0_arrangement-mat.pdf)
BOM. And improve as those specify that the screws are in the kit, but do
not specify the type at all (just
[pan-head](http://en.wikipedia.org/wikis/Screw#mediaviewer/file:screw_head_types.svg)
(image A).V6.0Erik van der BijErik van der Bijhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/62V5 - Obsolete L1: CTX10-1A-R, Dual Winding Shielded Power Inductor/Transformer2019-11-08T18:18:04ZErik van der BijV5 - Obsolete L1: CTX10-1A-R, Dual Winding Shielded Power Inductor/TransformerSee https://forums.ohwr.org/t/ctx10-1a-r-has-been-discontinued-by-eaton-cooper-bussmann/848245 for the proposal of an alternative type.V6.0Erik van der BijErik van der Bijhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/63V5 - make C41 "do not mount"2019-11-08T18:09:27ZErik van der BijV5 - make C41 "do not mount"I recommend we make C41 "do not mount", because removing it stopped the instability in the voltage regulation feed back loop. However other layout changes may requires some capacitance to be fitted. The final layout will need to be checked for control loop stability to answer this question.V6.0Erik van der BijErik van der Bijhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/4EEPROM type not compatible with VITA 57.12019-10-08T15:31:25ZDimitris LampridisEEPROM type not compatible with VITA 57.1In order to comply with VITA 57.1 standard, the FMC EEPROM needs to be
changed to 24C02.https://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/1V5 - Obsolete inductor L1: CTX10-1A-R2019-08-05T11:20:36ZErik van der BijV5 - Obsolete inductor L1: CTX10-1A-RProducer of cards mentioned that the inductor L1, CTX10-1A-R is
obsolete.
This is a transformer used to generate the negative supply voltages.
For the 2018 production the supplier managed to buy the component via a
broker.https://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/61C5/C37 22nF 200V difficult to obtain2019-02-12T11:15:06ZErik van der BijC5/C37 22nF 200V difficult to obtainDuring production of the prototypes, it was found that C5/C37 22nF 200V
are difficult to obtain. 100V or 50V are easier and in stock. These are
used for the capacitive connection of the front-panel and standoffs to
Gnd.
- Verify if a 100V or 50V version may be used for C5 and C37.
- Modify schematic and BOM accordinglyMaciej FimiarzMaciej Fimiarzhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/60Stand-off and front-panel grounding scheme possibly not correct2019-02-12T11:15:05ZErik van der BijStand-off and front-panel grounding scheme possibly not correctThe standoff and front-panel of each side are connected together and
optionally connected to Gnd via R//C.
The FMC spec reads:
- Rule 3.19: FMC front-panel shall be isolated.
- Rule 3.23: the standoffs shall be tied to ground.
With the SMC connectors that are screwed onto the panel, we anyway
connect the front-panel directly to the circuit ground. This violates
Rule 3.19, but is in my opinion good anyway.
At the same time it means that the R//C on both sides are not useful.
- Consider removing C5//R1 and C37/R98 to reduce the BOM (only place
where 22nF is used).
- In this case still connect the mounting holes of the front-panel
directly or via 0 Ohm to Gnd as it may give a better connection than
the contact via the SMC connectors.Erik van der BijErik van der Bijhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/59Change resistor values for availability2019-02-12T11:15:05ZErik van der BijChange resistor values for availabilityFor availability reasons two resistor values need to be modified
(120<s>121, 510</s>\>511)Maciej FimiarzMaciej Fimiarzhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/5856 Ohm resistor in 1812 package not easily available2019-02-12T11:15:03ZErik van der Bij56 Ohm resistor in 1812 package not easily availableThe 56 Ohm resistor in 1812 package (used for the External trigger
input) is not easily available. Replace by 50 Ohm type.https://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/57Temperature chip to be replaced2019-02-12T11:15:03ZJavier SerranoTemperature chip to be replacedI am not 100% sure, but I believe the thermometer chip in this card is
different from the one used in the PCIe carrier board. The advantage of
the latter is that it also contains a unique 64-bit identifier, very
useful for stocks and card lifetime management.Erik van der BijErik van der Bijhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/56Vishay diode used obsolete2019-02-12T11:15:02ZErik van der BijVishay diode used obsoleteWe received a message from Farnell (see attached file) that the VISHAY
MBR0530PBF, DIODE SCHOTTKY 0.5A DIRECT has become obsolete.
They propose to replace it by ON SEMICONDUCTOR MBR0530T1G, DIODE
SCHOTTKY 0.5A 30V SOD-123 (Farnell 1431036).
*Actions**
- verify if proposed alternative is compatible (package,
characteristics)
- modify schematics
- update production files
### Files
* [FARNELL.TXT](/uploads/d0106f74728f0f6d64d46e50cb80e4f5/FARNELL.TXT)Maciej FimiarzMaciej Fimiarzhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/55Verify if connectors are close enough to front-panel.2019-02-12T11:15:01ZErik van der BijVerify if connectors are close enough to front-panel.It seems that there is a little too much space between the SMC
connectors and the front-panel. In principle they should almost touch
(leaving just a few tens of a mm space).
Not clear if dependent on front-panel or connector assembly as the three
prototypes are slightly different.Maciej FimiarzMaciej Fimiarzhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/52Temperature sensor not near hottest spot on board2019-02-12T11:14:59ZErik van der BijTemperature sensor not near hottest spot on boardThe temperature sensor IC (IC13) seems to be at a rather cool place on
the board. Consider moving it nearer the components dissipating the most
(DC/DC and drop-down regulator).Maciej FimiarzMaciej Fimiarzhttps://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/44Inductors: BOM not correct2019-02-12T11:14:53ZErik van der BijInductors: BOM not correctCertain inductors are not correct in the schematics and in the BOM.
Request new symbols and correct. Verify package types to see if no PCB
revision is needed. May become a variant.
- L2 etc. (14 times): (±20% 360mA Wire Wound Chip Inductors 4.7uH
KEMET L0805C4R7MDWIT).
Replace by TAIYO YUDEN CB2012T4R7M - Farnell 9544526.
<!-- end list -->
- L3 etc. (4 times): (5% 250mA SMT Inductors SIMID Series 1uH EPCOS
B82498B1102)
Replace by VISHAY DALE IMC0805ER1R0J01 - Farnell 170-4104.
<!-- end list -->
- L4 etc. (8 times): (25% 1.2A SMT Chip Bead for Power Line
390R@100MHz TDK MPZ1608R391A)
Replace by TYCO ELECTRONICS 36501JR27JTDG - Farnell 1265492RL.https://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/43V2: capacitors selecting clock to use are all mounted2019-02-12T11:14:52ZErik van der BijV2: capacitors selecting clock to use are all mountedIn the first production of 10 cards of the V2 version of the card, the
capacitors that select the clock input are all mounted, shorting several
clock inputs.
Verify if the schematics or production documentation is wrong.
\- signaled by Tom.https://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/41V2 - C44 is too close to the edge2019-02-12T11:14:51ZProjectsV2 - C44 is too close to the edgeC44 is too close to the board edge.
Has already been pulled out on one board.
C2 is also quite close to the edge.https://ohwr.org/project/fmc-adc-100m14b4cha-hw/issues/40V2 - solder mask cutout badly placed2019-02-12T11:14:50ZProjectsV2 - solder mask cutout badly placedThe solder mask cutout under IC9 is badly placed.