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High Voltage Logic

Posted: Tue Jul 29, 2003 9:03 pm
by i_myself_matthew
I need a way of driving nixie tubes without breaking the bank. Nixie tubes are gas-filled tubes with numbers that run off of high voltage (about 170 volts DC).
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Image<p>Each digit is connected to a pin, and logic chips are typically used to complete the circuit from B+ to ground. When not connected, each pin has around 60 volts. The current drawn when on is no more than 3 milliamps.<p>Does anyone know where I can buy a chip that is cheaper than the $7 NTE replacement for a 74141?
I would really like to avoid discrete transistors, as I have 8 tubes to drive, and I would like to avoid multiplexing.<p>Sources for (relatively) cheap 74141 chips, or new chips that can do the same thing would be greatly appreciated.<p>Thank You

Re: High Voltage Logic

Posted: Tue Jul 29, 2003 11:12 pm
by L. Daniel Rosa
You might try other outfits. As I recall, NTE never had the best price. If that fails, you can try a (CMOS) 4028 (BCD to decimal decoder) with NPN transistors on each output pin. If you do this, a 2N2222 can probably handle the 60V, but a 2N5550 is a much better choice. This is likely to be around $3 per digit.<p>Oh yes, other sources. I haven't looked, but Digikey, Jameco, MPJA, and Electronix Express are some popular retailers.

Re: High Voltage Logic

Posted: Wed Jul 30, 2003 8:24 am
by russlk

Re: High Voltage Logic

Posted: Wed Jul 30, 2003 7:43 pm
by i_myself_matthew
Thank You, Electronix Express has the 74141 for only $2.50 a chip, much cheaper than other places.

Re: High Voltage Logic

Posted: Tue Aug 12, 2003 10:06 am
by QUINNQUIXOTE
There's always ebay.... <p>Also Supertex offers an HV5530 that is a shift register and 32 high voltage line drivers - they run about $7-8 on mouser and can be cascaded, have digit blanking, etc -eliminates a lot of components, all you need is a pic or similar controller to feed serial data to the HV5530 which will drive four tubes in a clock at minimum!