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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


0

How about a unijunction (relaxation) oscillator e.g. 2N2646 See http://baec.tripod.com/DEC90/uni_tran.htm for design details


1

Probably everyone knows about this 3-component oscillator- but it's hardly suitable for any serious application. simulate this circuit – Schematic created using CircuitLab


2

"How would I calculate the values for the positive feedback capacitive divider network? Also, is there any universal way of analyzing transistor feedback circuits? I would really appreciate a step by step guide." What is your intention for positive feedback? For normal amplification purposes we use negative feedback (dc and ac). There is one application ...


2

While the above answers are correct, in the late 70's through the early 90's sometimes simple CPU's were constructed from TTL logic. While you may or may not want to get into such a project, it is interesting concept. Because the CPU is spread out and hand wired you can probe around and see it in its entirety rather than just as a small black box. Here's ...


8

For practical purposes of getting it working on your desk, you probably want an FPGA. In order to make sure it works, you should simulate it first with a program like Modelsim. This enables you to iron out the bugs before buying any hardware.


3

Texas Instruments, et al. have almost unbelievably extensive stables of digital logic functions available which can be assembled into pretty much anything you want. Go here and here , then check out HC (HCMOS) to get started.


-1

Charging up a capacitor quickly and discharging it a bit more slowly is something that you probably do every day without noticing - charge your phone much? That battery acts a lot like a cap. It all has to do with the time constant, which is a product of resistance and capacitance, simply put. So, to charge fast, what kind of resistor would you have to use ...


0

Well, you know that to charge a capacitor instantly will require infinite current, right? And we know that all real-world power sources have some finite resistance associated with them, as do capacitors (ESR). However, as your intuition suggests, if you just pop your capacitor across a supply you are depending on the parasitic resistance to limit your ...


3

This is not going to be easy since it's hard to make semiconductor circuits that switch nicely at only 700 mV supply. I'd probably use a boost converter chip that can make 3.3 V from the 700 mV, then run the control electronics off of that. Now you can use widely available digital logic to create a nice clean on/off signal that drives the final power ...



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