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What you need is the Direct on line starter with timer. Since nothing is free in this world and everything comes with a price, get your "client" to agree to buy for you the simple starter with red+green push buttons on it and get it linked to the timer unit. This starts the load with a momentary press on the green button and it drops the load off during ...


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You have all of the address pins constantly held low giving the address 0000, you have all of the data bits held low except for bit 1 giving a nibble (or word in the datasheet) of 0001. Using !ME and !WE (to replace the overscore notatation used for active low in the datasheet) - you have !ME always low, and (hopefully) can toggle !WE low by closing the ...


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This is a memory IC, so it remembers the state of D1-D4 when ME is low and you pulse WE low. The leds that should be OFF are R1, R2, and R3. R4 should be ON. To change which LED's are ON you need to change the state of the memory inputs (D1-D4), then bring WE low then high again and see the change. The data outputs of this IC are inverted, so to turn an LED ...


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Your client needs a start-stop contactor and timer. Press the green button to switch on power. When power goes off contactor will drop out. When power comes back on start the timer. When time reached press green button. It has an off button too.


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This is a very simple thing to do with a small microcontroller. The on and off buttons would be just inputs to the micro. The micro would sense AC power via a opto-coupler and control a relay that switches the AC on/off to the equipment. Even a small PIC with internal oscillator can do this easily. Of course if your client can't even afford a "smart ...


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My experience is limited to using rather than designing the "Due compatible" Duet board designed by Think3DPrint3D and RepRapPro using the same microcontroller, it uses 10pF external caps https://github.com/T3P3/Duet/blob/master/Duet0.8.5/Duet0.8.5_Schematic.pdf digging around you could find the crystal capacitance pretty quickly, but as you and the other ...


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Rather than just moving wires to change your inputs, it would be well worth your while to get a DIP switch and a bunch of resistors (or a SIP resistor network). I would hook the 7489 up as follows: simulate this circuit – Schematic created using CircuitLab The SIP network is nice because you can plug it into your breadboard right next to the ...


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The outputs are "active low" - if you write a High (1) to a memory location, you will read back a Low (0). The outputs are "open collector" which means that the output transistor's collector has no connection inside the chip - you need to add a pull-up resistor to see a high output. Your LED + 470 ohm to +5 will light the LED when the output is low, which ...


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You need to connect CAN_TX and CAN_RX to a CAN transceiver such as an MCP2561. The CAN transceiver will provide the CAN_HI and CAN_LOW signals. For an example, look at how they implemented the dsPIC33EV 5V CAN-LIN STARTER KIT evaluation board. The schematic for the evaluation board can be found in Appendix A of the dsPIC33EV 5V CAN-LIN Starter Kit User’s ...


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Consider LTC3633A. I used it for several designs, it works very good, predictable and according to the datasheet. I suggest using MLCC X7R or X5R for input and output filters (no aluminum or tantalum capacitors!) and running it about 2.5-3.2 MHz. Two or three "layers" of LC or LRC filters are enough to meet RF requirements for interference. Make sure that ...


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In principle that will work, but probably not well. Efficient coil gun drive requires the coil to maintain current while the projectile is accelerating, and only cut the current when the projectile is in the coil. If the current persists after the projectile exits the coil it will act to decellerate the projectile, which does defeat the purpose of the whole ...


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Loudness control From Elliot Sound Products Beginner's Guide to Potentiometers: Ah! Another one ... Most pot 'gangs' are 3 terminal types, but there are some with a tapping partway along the resistance element. This was used in the bad old days to create a 'loudness' control, where the bass and treble are increased at low levels to compensate for the ...


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It is a pot with a (probably center) tap. They used to be more-or-less common in audio design, typically in the 'tone control' circuit. See, for example, this guitar amplifier schematic:


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In Altium you have to place ports on the schematic of the sub-circuit to define its outputs and inputs. Example: Once this schematic is ready and you have defined all of its ports, you should switch to the schematic into which you want to place an instance of this sub-circuit. Now, select the Create Sheet Symbol From Sheet or HDL option from the Design ...


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You can regard both types as complementary, if the circuits are identical but one is just the "upside down" version of the other, everything applies to both architectures you only need to watch the directions of currents and voltage polarties but that is it. Lastly, what is the difference between these two architectures?(in general) They are identical but ...


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In my opinion, the "right" way to do this is to instantiate the LED sheet 20 times, and route one to the next explicitly. This may seem more messy, but it explicitly defines a relationship that you're trying to trick the schematic compiler into building.


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I think this may be your issue. You need to put the sheet name first in the argument list. But note that it's totally acceptable to make multiple sheet entries from the same schematic page and just route it explicitly too.


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You can almost work out the circuit from the photograph, since the PCB traces are fairly visible through the substrate. The circuitry to the left of the power switch generates the high-voltage to charge the flash capacitor C3 at the top. The circuitry to the right of the power switch provides the trigger pulses to the trigger transformer T2. There's a ...


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I presume the labels are intended to be relative to the device, not the Arduino. In other words, "Dig Out" means "Digital Output from the Sensor" and similar for "Dig In". You would connect the digital output from the sensor to an input of a microcontroller or other circuit.


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Eagle paints many of the gerber features with a raster of 0.3mm lines, making it difficult to seamlessly identify features such as pads or tracks, versus polygonal pours, ground planes and so forth. If your version of Eagle supports import, you are mostly done and dusted. If not, other options would include converting to another file format which you may be ...


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As of Eagle 7.5, this is indeed possible. It's a simple case of File->Import->Gerber from the layout editor. There is a video demo on YouTube. As others have mentioned, there is no real DRC checking possible of the imported file as the Gerbers contain no information on nets and connectivity. Eagle simply imports all of the various shapes and lines ...


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No. A standard Gerber format file contains only primitive shapes and positions. It contains no concept of WHAT any of the shapes represent, or even that it is an electronic printed-circuit board. However, the Gerber format is a quite simple and strightforward text file. It can be edited in any low-level text editor. So, if it is worth the time and ...


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Essentially, the Gerbers are vector drawings (that PCB fab equipment understands). In a Gerber, you can have a rectangle, but the Gerber doesn't "know" that this rectangle is actually a pad, and it's a part of footprint that has other pads. Gerbers don't carry the schematic information: all traces are just lines (or polylines) for x1,y1 to x2,y2. Afaik, ...


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The dashed oval outline designates a conductive overall shield. Typically a braid of small, bare copper (or tinned copper) wires. However ordinary power cables just have the safety ground as a third, insulated internal wire just like hot and neutral. Note that back in vintage days (as when those diagrams were drawn) the color standard in North America was ...


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I see several details in your drawings. 1) The top drawing is of a shielded power cable, and the power can be AC or DC. 2) Pin 'E' on the J2 connector is Earth ground for the chassis and power. The J2 connector has a gnd symbol at the bottom to clarify it is earth grounded.3) J2 also shows built-in capacitors to filter out EMI noise from either direction. I ...


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I would agree, this appears to be a conductive shield around the the 2 leads in the power cable, the clue here is the military spec on this device, this is done generally to try and prevent Emf interference on the operating device


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The dotted lines that circle the bundle of signals is often used to delineate a cable bundle (e.g. wrapped together in a sleeve), and when signals are connected to it, that generally means that it represents the (conductive) cable shield. The second thing you circled (in J2), is a typical representation of Earth ground. I take it to mean that the chassis ...


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Connect them all. The reason why multiple pins of the same potential are brought out of the die is for two reasons. 1) this reduces the resistance. When you do that you reduce the voltage bounce that occurs from current pulses that are formed upon switching. So you get a cleaner voltage source on the internal power rail. 2) it reduces the inductance of ...


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Generally, a device with multiple supply/ground pins intends for those pins to be externally connected to the appropriate supply/ground. It is particularly important to connect the ground pins together using wide traces or polygons/planes to avoid ground loops. The datasheet, section 1.1, for the 328p indicates three specific power connection types: VCC, ...


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Connect all of them and more importantly apply very localized decoupling capacitors on them all.


1

A simple and direct answer to your main question, is that this is one way of providing the differential voltages that the op-amps need (+ & - 5v). By floating the ground (to +5v) the single 10v source can supply + & - 5v! You should now be able to understand that the output of op-amp I, is being used. It creates a virtual ground (or reference ...



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