Sunday, November 30, 2025

Replacing some chips on 1130MRAM board based on testing

›
TOGGLING STORAGE READ AND OBSERVING THE SENSE OUTPUTS I have the board set up with a switch that will drive a rising edge on the +Storage Re...
Tuesday, November 25, 2025

Finishing new PCB for 1130 MRAM, waiting on memory chip

›
CONNECTOR PINS INSTALLED AND MORE CHECKING ON THE PCB I use square profile gold plated pins, soldered onto the PCB with the correct spacing,...
Sunday, November 23, 2025

Building new version of the PCB for 1130 MRAM

›
USING SOLDER PASTE AND HOT AIR GUN FOR ALL SOLDERING Because so many of the chips are tiny footprints with very narrow pin spacing, I decide...
Tuesday, November 11, 2025

More work on retriggering issue with 1130MRAM

›
GOOD SUGGESTION FROM A BLOG READER One of the blog readers, Merlin Skinner-Oakes, suggested that I add a low pass filter to the output signa...
Thursday, October 30, 2025

1130 MRAM - quick check after removing large buffer capacitors

›
PREVIOUSLY ADDED CAPACITORS WHEN SUPPLY SAG SUSPECTED A while back I worried that the rails on the PCB were sagging during the heavy output ...
12 comments:
Tuesday, October 28, 2025

1130MRAM smoking gun found

›
SCOPE ON 3.3V AND GROUND, TRIGGERED BY THE ANOMALY I set the scope on the yellow trace and triggered on the first fall of the +Storage Read ...
3 comments:
Saturday, October 25, 2025

1130MRAM spurious retrigger - what it can not be then musings

›
NOT A FAULT OF THE CONTROL SIGNALS The control signals that fire off the timer chips are +Storage Read and +Storage Write . They are produc...