T&L Publications

I'm an EE - I design analog circuits for CMOS integrated circuits. This mainly means spending a lot of time in front of a simulator nowadays. But I still like to get in the lab (unlike most in this particular specialty), and enjoy reading about projects in Nuts and Volts. Got started reading it beca...

Thanks again for the info, bodgy.<p>The Needham's programmer is a stand-alone unit with its own power supply; I'm sure it generates the 12 V or so to program parts by itself.<p>My understanding was that some PIC's actually can generate the programming voltage themselves; I thought that this is what ...

If it seems kind of awkward to work with the LM317(s), take a look at the TL783 from TI. It is good for 125 V from input to output. Figure 18 in the datasheet (linked to at the web page shown below) shows how to short circuit protect it when the input-to-output voltage is potentially greater than 12...

Thanks for the reply, bodgy.<p>So, basically you are saying that the regular programmer can work in a serial mode, and I can fly the wires over from the programmer to the target board. Then if I follow the rules you list for a couple of the pins, it should work okay. Right?<p>The other point, if I u...

Hope this hasn't been answered before, since there seems to be a lot of PIC processor info on this forum. But when I did a search, I couldn't find this particular topic addressed:<p>I've been using PIC processors with a Needham's Electronics programmer for years, and it's worked just fine. But it is...

I assume you mean 500 microhenries (uH), right?<p>If that is the value, and assume you have only an audio generator capable of 20 kHz maximum, the inductive reactance at 20 kHz will be:<p>XL = 2 * Pi * 20*10^3 * 500*10^-6 = 62.8 Ohms.<p>That's pretty workable. Just put a 62 Ohm resistor in series wi...

brad087:<p>Yes the way you did it should work fine. Making the voltages across each element equal will ensure that the inductive reactance equals the resistance of the resistor. Then the rest is math, just like you say. Probably easier than the way I said to begin with; it eliminates one step.<p>Reg...

Not so sure anymore that everyone has to do the math at least once. My recent experience with trying to hire a couple analog designers would indicate not...<p>Regards,
Todd

"In other words, LOTS of math, or a simple inductance meter."<p>-- indeed. But the math is straight-forward algebra, and presumably one with access to an "inductance meter" wouldn't have asked the question. And a guy might even gain some insight with the indirect method.<p>Then a...

Do you have access to a meter that can measure AC volts and AC milliAmps? You also need some kind of sine wave generator appropriate to the value of the inductor (lower values work better with higher frequencies).<p>Without an idea of what value inductor you have, this may be an iterative process. B...

"1N" and "2N" prefixes are part of the so-called "JEDEC" registered part numbers, which are industry standards. Believe it or not, the "1" implies 2 useful terminals (like diodes), and the "2" implies 3 useful terminals, like bipolar transistors.<p>F...

Just built it tonight, and I get an arc, but it doesn't travel. Moving the rods affects where the arc decides to reside, but doesn't seem to make it want to move. Anyone else solve this problem?<p>I think maybe the arc is not lasting long enough in my circuit. How long are peoples 'on' times (I gues...