New answers tagged

3

It could use 2 diodes. Diodes will only conduct current in one direction, but they do drop some voltage. I assume your 1V voltage source is actually a higher DC voltage? simulate this circuit – Schematic created using CircuitLab


0

Yes, but not with that circuit set up. You'd need a different one, and large capacitors. Edit: More explaining is necessary. The circuit you have provided is a bridged topology for only one channel. You can either double this circuit and have one copy drive each channel separately OR you can use one amplifier with the circuit at the top of the data sheet ...


0

Amplify the signal and feed it though filter, buffer the output of the filter and rectify the voltage using a full wave rectifier, a smoothing capacitor and another diode to get rid of the ripple voltage. Send the output into a properly DC biased amplifier stage that will drive the LED. The DC signal will be low for values outside the cutoff but approach a ...


3

To detect the frequency of a relatively pure tone you don't need filters. All you have to do is convert the fundamental frequency into a voltage, using a frequency to voltage converter such as the LM2907. You can then fed the voltage output into an LM3914 dot/bar LED display driver.


1

Use tandem stepper motors or synchros or servo motors; one with a hollow shaft to which one hand will be attached, and one with a solid shaft to which the other hand will be attached, the solid shaft rotating in the first shaft's hollow space, like this:


0

So a little bit of filter theory kinda puts a little mud into this project. Unless you're looking at high-order filters (read complicated), a first order filter only rolls off at 20dB/decade which means your filters won't isolate their bands very well. This might work for 250Hz, but what about 290Hz? You may have so little filtering that 3-4 lights light up ...


5

When the opamp output voltage falls the capacitor C2 charges trough the base of Q2 until the capacitor positive terminal reaches a voltage so high that current cannot flow anymore. As Q2 is a pnp transistor this current trough the base causes it to conduct, charging C3. When the opamp output begins to rise again, the negative terminal of C2 is brought up in ...


1

You are not a million miles away with your estimate. BUT you need to think about what your device is going to be doing to make a real estimate. Use your calculations of: 500mAh / 59mA = 8.47h if your device is only going to be used as a receiver. Or use the higher value of: 500mAh / 278mA = 1.8h if the device is going to be used as a transmitter. But ...


8

There are a few good reasons: - Only one diode forward voltage drop Only one diode as opposed to four 0V can be an incoming power line as well as the outgoing DC side You can use one secondary of a transformer and two diodes to get a split V, 0, -V supply: -


1

Use of the words "Port" and "Entity" suggests that you are working in the VHDL language, perhaps your schematic editor is a tool that allows the visual creation of VHDL designs. The actual meaning of the message is clear : you are trying to connect a signal to a pin that doesn't exist. For example, take this AND gate entity AND2 is port (A,B : in ...


4

Beginner electronics. Searching the internet is your friend. There are so many web sites for beginning electronics. One place to go : http://www.hobbyprojects.com/ Click this for another site With amplifiers, the word GAIN is used to describe how much more the output signal is compared to the input signal. You could search for "amplifier gain ...


0

You should be able to do this using NC (normally closed) relays. Simply have voltage across source 2's input pins trigger a reay in series with source 1 to open (turn off), and have voltage across source 3's input pins open relays on both source 1 & source 2. Sorry, I can't provide a diagram due to only having access to my phone & tablet right now.


1

All sources say "Improved EMI and RFI mitigation features" but I'm sure it's the same reason every other power connector is shielded... to stop the pins shorting out on metal objects unintentionally.


3

USB micro-B is known for its high mate/demate cycle specification relative to the other USB connector types. It achieves this by having the sprung contacts in the cable, rather than in the device. This way, only the cable is subject to deformation, and can be replaced if it becomes unreliable. The contacts in the device are fixed and so do not wear or deform ...


2

They likely wanted a contiguous ground shield for the high speed data (most high speed buses do have shielding for alien cross talk). Anything past that would be pure speculation.


0

You can use the 'report_power' at any stage of the flow to find out the power measurements.


3

My take on this. Are there any reasonably priced eval/dev boards for USB chips ? I assume with "USB chip" you mean a programmable microcontroller with USB peripheral. Yes, plenty. But if you want to stay focused, start looking from where you are now. And by that I mean; how much and particularly on which embedded platforms are you familiar with? Some ...


6

This is not a complete answer, and your question is too broad for that. I can give you my experience. Are there any reasonably priced eval/dev boards for USB chips? I can't answer this. Can you recommend any specific chips? I have used the PIC16F1454 in two projects. It has everything built-in for use as a USB peripheral. You literally only need ...


0

10 pin 0.1inch spaced pin headers on your boards, mount 'smd' style , flat on your board, (or get SIP right angle pin headers). Let the pins hang over the edge of the board, parallel to it. Build a 'veroboard' backplane with 0.1inch spaced female sockets into which the headers plug. sockets at right angles to the backplane. Cheap and nasty. You can do the ...


1

There are some broad guidelines, but each situation is different, and emphases will vary. Wasteful of space? If your circuit must fit in a USB stick, you cram all the components together. But then you have difficulty debugging, reworking, adding the bit you forgot. If you can generous with 'empty' space on your first layout, do it! Put all the ICs with pin ...


3

I think that's excessively big. I normally use 8 mil width and space unless there is a good reason not to, and I don't see one here. 8 mils is something just about any board house in the world can do, usually with a little extra margin so that nothing is being pushed to the limit. If you know the board house and that they can do finer line/space, then ...


0

As Bruce said you can get it from an existing Eagle file like the one in A10 OLinuXino project. You can then either extract the lbr using exp-lbr.ulp or you can copy it using the GROUP and COPY commands in the OLinuXino schematic and then PASTE command in your schematic. You can get it from here as well http://wp.me/p2D6cb-Tz



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