Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [dimensions]

60 questions
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Is there any pattern or standard to through-hole resistor sizes?

I've long been under the impression that a quarter-watt resistor has a standard package, and a half-watt resistor has a standard package, etc. But I've recently gotten through-hole resistors which are not in the expected package size. I've done an…
Stephen Collings
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Difference between 1206, 0805 and 0603 SMD resistor

What is the difference between a 1206, 0805 and a 0603 SMD resistor, as far I know they all have a resistance of 10.7K? I going to need one for my little 5v DC buck converter.
Artonn
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What does "V.A." mean in datasheet dimensions?

I'm looking at a datasheet for an LCD panel (pdf link to datasheet). I don't understand these two encircled dimensions: What does the acronym "V.A." mean for these dimensions? I have referenced a couple of other questions here on EE, but they don't…
skrrgwasme
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Reading dimension in datasheet

This is my first time making pcb layout. I am also quite unfamiliar with datasheets. I am using DS90LV019 (the figure is attached below). What is the actual length of this IC. Does (0.335-0.344)/(8.509-8.738) mean the length is 0.0393 inches?
Sui
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What are the max. overmold dimensions for USB-C plugs?

In contrast to earlier USB specs, the USB-C specification doesn't seem to define a maximum width and height of the overmold part of the plug (according to figure 3.3, there is just a length defined). 1) What is the idea behind not even giving a…
Philippos
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What is the correct pin spacing for this footprint?

I'm trying to import an IC footprint into CAD software and can't seem to nail down the exact dimension for pin spacing. The two supporting documents seem to conflict with each other (Land Patterns here, and Package Drawings here). In the drawings…
Tanenthor
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Why do they put some optocouplers in 6-pin packages?

Example: It is obvious that an optocoupler which provides a pin for the base of the internal transistor (e.g.; PS2621) cannot be in a 4-pin device. My question is not about this kind of optocouplers. But, an optocoupler which gives out only the…
hkBattousai
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Through-hole footprints: pad size from technical drawings

I'm creating some footprints for through-hole components in KiCad, and I've got some issues determining the correct pad dimensions from manufacturer's technical drawings. As an example, here's the drawing for a Fairchild BC547 - TO-92 package (line…
Macmade
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Missing footprint dimensions in Datasheet

I am preparing to start work on designing a board that uses a component in a PowerFLAT 5x6 package (the component is a power Schottky rectifier, part STPS30M100DJF from STMicroelectronics). The datasheet is here:…
DerStrom8
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What is the pin diameter for this part?

What is the required pad diameter for the following part ? HM2J07PE5118N9LF Maybe its late and I'm just not seeing ? The recommended PCB hole layout usually contains this information but I just don't see it.
efox29
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How to find the right connector?

I have gotten the task of finding an appropriate connector for our application, but given so much information there is on connectors, I don't even know which information is relevant. So this is the task; I have a cable that has a strand of 10…
Samo Smodis
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Reading dimensions for datasheet

I have the following PCB datasheet, but I am very uncertain as to what it is saying. Some of the dimensions each have 3 numbers, which I took as nominal, minimum and maximum values, however, the sides do not add up. The datasheet says that each side…
Samyak Shah
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pick and place cannot read LCC module

The assembly house has a P&P machine (Yamaha i-pulse M4S) and the export file is from Altium. All components are read from the machine fine except an LCC gsm module MG323-b which has a particular think that i'll try to explain: As you see at the…
TBELO
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What is the maximum height (thickness) per slot for a finished (soldered/populated) PCI express card?

The main question is: Defined by maximum allowable height from the surface of the PCB on both sides (soldered pins and components), or whatever metric experts think would be most useful in decoding an undefined "card height" measurement in inches as…
Rook
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Have AAA batteries gotten shorter?

I'm finding that the standard AAA battery from most manufacturers (including Duracell and Energizer) have gotten shorter and don't fit as tightly in my alarm clock and HP-48 calculator. The old Duracells (I dated these as 2015 when I inserted them)…
D Duck
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