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2

I found the Molex 5569 library you're using. Whoever made this library did something very odd. For each square through-hole pad, they also added a co-centric hole on top of it. So there's a pad and a hole in the same spot for every pin. Eagle is programmed to isolate pours away from holes, which is why you're getting an isolation circle around each square ...


5

I've designed over a dozen FPGA based boards that employed a wide range of different types of FPGAs from low power Lattice Mach X02s to high performance Virtex 6's with 24 SERDES channels. The normal steps I follow are: Find a COTs board (similar to MarkU) and get a rough idea of the internal FPGA resources you will need, in particular I pay attention to: ...


0

The ER341245 data sheet says it can supply 450mA continuous, and 1000mA pulse. So it does not look like a capacitor is needed to protect it from damage by a 60mA peak. According to the data sheet the battery capacity is quite sensitive to the discharge rate, so trying to smooth out the discharge rate might have some benefit. "peak last 25ms and its ...


2

With only simple logic gates, you're going to be "putting a crazy amount of them" on the four MSBs. Optimizing your logic can help reduce the number of gates (there are two that start with 11, so they can share some gates, for a start). However, if you were to spend a few pence and invest in a 74xx154 4-to-16 decoder then the 16 possible combinations of ...


1

In principle it is ok but it does suffer from shoot-through's during PWM transitions. This is compounded by the fact that P-TYPES switch slowed than N-TYPES. Depending on how much current you plan to draw through the MOSFET's you could simply solves this by putting a diode-resistor pair in parallel with the already present gate-resistor (while possibly ...


1

Single-transistor BJT amplifiers won't come up trumps for all the "rules" you have written at any frequency. For instance, you require an amplifier so I'm assuming you want voltage amplification. OK so far? The collector delivers a current output signal and not a voltage signal. This means that this current signal only becomes a sensible voltage signal ...


4

At my company, we've previously designed some custom FPGA boards, and have recently started using commercial off-the-shelf ("COTS") FPGA boards with custom FMC daughterboards. Prototype stage If you're still in the early project definition stage, plan on buying at least one COTS FPGA board for prototyping. You can wire up one of your sensors to the I/O ...


4

I think a good starting point for a custom PCB equipped with a FPGA will be the reference design boards from the FPGA vendor. You can inspect these designs for example for the power supply, but be aware that reference design boards are sometimes undersized. We had many trouble with Xilinx ML605 boards loosing there configuration, because of an undersized ...


0

I was also looking at something similar. If you want to run 802.11 and 802.15.4 on a single transceiver / chip It would in someways impossible if the chip cannot support DSSS and QPSK. Even if it does you would be looking at rewriting 802.11 stacks to make it work. look at the following product for a better and a easy implementation of two protocols on a ...


1

Design Spark has full capability to let you create your own schematic and layout symbols. Use that capability.


2

There is no way to tell whether you circuit will "work" since you haven't said what it should do. "Working" means the actual behaviour matches the specification. Obviously that requires a specification, which is missing in your case. What this circuit will do is to blow out the LED when the light is interrupted. Whether that is the desired behaviour and ...


6

I'm sorry to say that your circuit will not work: The MOSFET RDS(on) (2.8 Ω) is too big compared to your load resistance (2.5 Ω). If your load needs 2 V to work properly, be aware that it will only have around 1 V (assuming the MOSFET was fully on, which as mentioned above, it won't be). The LED (indicating if the load is powered) has no current limiting ...


5

In addition to the too low supply voltage there is another issue. If the LED is intended to light when the load is activated you will need to turn the LED around the other way and place a resistor in series with the LED to limit it's forward current. In the end the LED may not even light if the supply voltage is kept lower than the forward voltage drop of ...


7

It won't work, your MOSFET has a VGS(Th) of 3 V. Your supply is only 2 V. What is this circuit for; if we know we can help you better?


3

There were quite a few 3-input gates made, with three circuits per package. This meant that 12 pins would be needed (3 inputs, 1 output) x 3 and adding VCC and GND uses up all 14 pins in a 14-pin package which was very popular at the time these parts were designed 40 some years ago. Here are the 3-input logic ICs I am aware of: triple 3-input NAND ...


4

Try searching yourself at a distributor such as Digikey to get some idea of availability. I'll take you through a step-by-step if I was looking for, say, a NOR gate with at least 4 inputs. I'll be primarily interested in 4000 series CMOS or 74HC CMOS families (usually it would not be for the same application). First, get on the site and search for NOR ...


1

There are quite a few more-than-two input logic gates available. For example, the 7400 series of logic gates is outlined on this wikipedia page. For 8-input specifically, there is: 7430 8-input NAND gate 744078 8-input OR/NOR gate



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