QuadPulserRev1DebugLog

Issues on prototype

• Resistor wrong on -1V regulator (should be 20k not 2k)
• Enables not connected to +V on LDO regulators (3.3V, 4V)
• Missing cap on output of 3.3V LDO
• ADC "reset" signal wired to incorrect pin on FMC connector
• Clock must be AC-coupled to ADC (with 100 ohm term upstream)

To Do list

(new items added at top)

• Move L1 to the front. It is likely to run into the carrier board on the back. OK
• The input connectors should not be marked "U1" etc but "J1" or "P1" etc OK
• The silkscreen text still needs some cleaning up, maybe Dan can say something about this. OK
• On the back, the oscillator is too close to other components IMO

ok

• Op-amp (THS4509)
  • Footprint, pinout OK
  • Need solder mask opening on center / thermal pad? OK
  • Add pin 1 mark (circle) on silkscreen between pins 1 amd 16 OK

• ADC chip
  • See ​adc_traces.jpgOK
    • No traces wider than pads OK
    • No traces between pads and thermal pad OK
    • No traces or any other copper between pads OK
  • Add component body outline on silkscreen OK
  • Add pin 1 / orientation mark on silkscreen OK
  • LVdd is a long skinny trace. Should be wider (25-40 mils) OK
  • Add traces from GND pins to thermal pad. OK
  • Ensure thermal pad is connected to GND, looks like it might be 3V3 now! OK
  • pins CFG1-4 and PDN are configuration pins we're not using and are GND. This is OK, but they should have traces maybe 100-200 mils away from the chip to vias (one shared via is OK) so if we've messed up we can cut the traces and wire them to something else. OK
  • Solder paste layout on ADC thermal pad per data sheet OK-ish

• U13 and U16 (regulators)
  • Shrink solder paste opening a bit away from other pins (check data sheet) OK

• U12 (dc/dc dual output)
  • Move TP1 away from part OK
  • Check data sheet for solder mask and solder paste recommendations
    • "SOlder mask defined" (SMD) "Non solder mask defined" (NSMD) pad types | It didn't look like the datasheet said anything so I went with NSMD
  • double check if it's a BGA (with solder) or LGA (no solder) type package | Only available in LGA; LTM8045 (Neg. Converter) available in BGA

• General
  • make all copper area boundaries on grid and separations all ~ 15 mils OK
  • Add mounting holes in front corners of board OK
  • Route SEN above power connector OK