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3

Could someone help me understanding the markings of this schematic? What the little numbers I circled in red and yellow are The numbers you have circled in yellow, are the BGA ball numbers on that IC (cut off on the right side of the schematic photo you included). The numbers you have circled in red, are the page numbers in this schematic diagram where ...


2

C59 isn't "providing power" at all. It's merely functioning as a bypass capacitor (in parallel with C49, C53 and C285) between that 1.2V supply rail and ground. All of the pins that are connected by that heavy line are connected together electrically.


1

As far as I know, Proteus is the only electric simulator where you can place a micro-controller, load a compiled program, connect other electrical components to the ports, and see how the system behaves. Despite being quite frown upon, I chose this way to learn and design my first microcontrolled circuits. And I'm still using it. Because: Building a ...


2

I typically use the footprint for a 0.1 inch pitch "pin header". You can then use either male or female connector strips, or just solder wires directly to the pads if you don't need to use a connector. But using the header/connector provides a convenient place to show where the external connections are in the schematic and on the board. But it does not ...


1

This is a current source symbol. It provides a constant current (whose value should be written next to the symbol), whatever the voltage across it. And basically, it's the opposite of a constant voltage source (ideal power supply). Its meaning is not different from the usual symbol with a single circle. Here are different symbols for current source: ...


5

Learn to love "Find Similar Objects". Right-click on the object, change 'Value' from 'Any' to 'Same' and it should find all the 1pF capacitors. It will highlight them when you click apply, and if that's right (and it should be, unless there are more than one type of 1pF capacitor, in which case you should apply some distinguishing feature) then click 'okay'...


9

Typically, resistor "multipliers" are represented as: KΩ (thousands of ohms), MΩ (millions of ohms), GΩ (thousands of millions of ohms) ...etc. Since the context usually makes it clear that we're talking about resistor values, it's common short-hand to drop the 'Ω' so that, for example, you can write "39K"* instead of "39KΩ". But, dropping the "Ω" ...


36

The idea is that the multiplier replaces the decimal point. This dates back to pre-CAD schematics which were hand drawn and then photocopied and reduced. A decimal point could easily get lost during the copying process. By writing 4k7 rather than 4.7k the risk of these errors was greatly reduced. R was used for a multiplyer of 1 because omega could easily be ...


9

Adding to the other answers, sometimes you may even see E used in place of R. So a 100 ohm resistor would be 100E and a 9.1 ohm resistor would be 9E1 for example.


16

It is quite common to see the letter "R" used as a decimal point. As in 47R9 = 47.9 ohms. And likewise, it is common to see the letter "K" or "M". For example 6K81 would be 6,810 ohms and 2M3 would be 2,300,000 ohms.


1

'Z' is often a designator for Transzorb, as is the symbol. However any SMPS I have ever seen normally use a 20mm MOV, which has a higher transient absorption rating. Confusing the issue even more is that 'Sidacs' use the same symbol, but are very expensive, often in the $20 to $40 price range. Though I do not see values such as the rating of F1, this would ...


0

Move the port to right side. Altium will change the port direction automatically. Wire will be disconnected. Then drag the wire and connect to the port.


2

In Eagle, single physical parts can be broken into logical "gates". This is meant for exactly this situation, where you have a collection of independent logic gates in a single package that share certain pins, like power and ground. In this case, there will be one gate for each inverter, and a separate one for the power and ground pins. This allows the ...


0

You need to add the supply in the schematic. Click the button with the four gates on it and then click onto your buffer. A menu will pop up and you can select the power pins.


4

Your circuit is a strange mix of upside-down-ness. Figure 1 shows a more-likely-to-work configuration. simulate this circuit – Schematic created using CircuitLab Figure 1. The standard solution to this problem. A few tips: Draw your schematics with positive rail on top and negative at the bottom. It will be easier to trace current flow from ...


1

The battery and diode polarity are opposite to what is required using NPN transistors. With an NPN transistor, the base and collector need to be +ve wrt the emitter for collector to emitter current to flow. If you substitute PNP transistors, I think the circuit might work.


2

Yes, there is a free circuit creating client. In fact, the Electrical Engineering SE has it as well! It is called Circuit Lab! I believe it's free to design a circuit and to run basic simulations but there are advanced features that will require a subscription.


1

Agreed, nothing turns up in English as specified - you might ask the manufacturers if English documents of those exact models exist. However, here is the next best thing: TX-2B/RX-2B: 5-function remote controller (thanks to Bruce Abbott) Comprehensible translation of the Chinese datasheet for TC117HS


4

Because these DDR's have merged drivers and on-chip termination they have an active termination calibration circuitry and procedure. The calibration resistor should be accurate , thus the 1% selection. Note that this resistor can be shared amongst die if the controller sequences properly. Look at this app note from Micron (opens a PDF) concerning the ...


3

1% is the resistor tolerance (its 'accuracy' value). The actual resistor used in the circuit must have a value that is within 1% of the specified 240R. The dot may be an orientation indicator of some sort. Could this resistor be one part of a network or package of multiple resistors?


1

Your power supply concept makes sense (using a buck converter to make 5 V from 24 V), but your motor driver needs work. The voltage follower you show in your second schematic won't deliver much voltage to the motor. The FET will likely need a few volts G-S to turn on enough to allow useful motor current. With the gate at 5 V, that leaves very little to ...



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