Wide-Temperature Industrial Storage — Common Engineering Questions
Engineering answers for wide-temperature (-40°C to +85°C) industrial memory and storage: NAND behavior, qualification testing, and...
Technical Resources
Selection guides, whitepapers, and engineering insights for industrial storage.
Q&A
10 items
What are the guidelines for trace impedance (e.g., 40Ω or 50Ω) for DDR3 signals and the required trace width for a given stack-up?
Practical answer covering common impedance targets for DDR3 and guidance on trace width based on stack-up, referencing JEDEC stand...
Is it acceptable to use through vias instead of blind or backdrilled vias for DDR3 routing to reduce PCB costs?
A practical field answer for engineers weighing cost vs. signal integrity: through vias can work for DDR3 if timing margins and st...
How do I compensate for an unbalanced number of vias in DDR3 routing, and what are the signal integrity implications?
Practical techniques to compensate for unbalanced vias in DDR3 PCB routing and the resulting signal integrity effects on timing, i...
Why Does DDR3 Memory Have a BGA Footprint with Two Columns of Pads and an Empty Column?
The DDR3 BGA footprint uses two columns of pads with an empty column to improve signal integrity, simplify board routing, allow de...
Can I swap data wires (e.g., connect DQ0 on the CPU to DQ1 on the memory) on the data bus between the CPU and a DDR3 x16 memory for routing optimization?
Swapping individual DQ lines between CPU and DDR3 x16 memory is not recommended for standard designs. Within a byte lane, some con...
For DDR3 layout, what is the acceptable skew tolerance (e.g., 25 mils) within a net class, and does the reset line require length matching?
Practical answer for DDR3 layout: skew tolerance within a net class depends on signal group (e.g., data vs. address/command), and...
How do I properly length-match the different signal classes (address/command/clock vs. DQ/DM/DQS) for DDR3 routing?
Practical guidelines for length-matching DDR3 signal groups: address/command/clock vs. DQ/DM/DQS. Covers why matching matters, typ...
What are the minimum number of PCB layers required for proper DDR3 fanout and routing to keep costs down?
Loongtion documentation does not specify a minimum PCB layer count for DDR3. General engineering practice recommends 4 layers for...
Systemd Boot Optimization: Why dev-mmcblk0p2.device Takes 4.5 Seconds on an Embedded eMMC System?
Learn why the dev-mmcblk0p2.device unit delays boot by 4.5 seconds and how to optimize eMMC initialization using kernel parameters...