[NEONIXIE-L] Neonixie 6 digit controller using DM8880 decoder drivers and B7971 Nixie tubes
DanielK
I bought Moses' Neonixie 6 digit Nixie Clock Controller to hopefully drive 6 B7871 Nixie tubes using 6 DM8880 High voltage 7-segment BCD decoder drivers. I need some help getting the clock built. Has anyone actually done this?
Here is the schematic using 74141's
http://www.neonixie.com/store/images/6-digit-nixie-controller-schematic-pic.jpg
1. Can anyone provide a simple schematic based on the above substituting the DM8880 for the 74141 and 7 segment B7971 instead of 10 digit tubes?
2. Since this is a direct drive design, is there a way to eliminate the need for the DM8880 for the tens of hours tube which is either blanked or a 1 in the 12 hour running mode? Could I just tie together the respective pins for the 8 and 12 segments of the B7971 tube and use an MPSA 92 transistor to turn on the cathodes?
3. Moses designed a display blanking feature for timed night time off periods. How can the DM8880 blanking input be used for the same purpose without using some logic to blank each tube separately?
I have uploaded the data sheet for the DM8880 in the Temp file folder.
Thanks for your help on this project.
Dan
DanielK
I would like to build a clock using six B7971 Nixie tubes with the Moses Neonixie 6 digit driver. I have enough DS/DM8880 HV BCD decoder drivers.
I uploaded the data sheets for the DS/DM8880 to the Temp files section on this site.
Here is the schematic for the controller
http://www.neonixie.com/store/images/6-digit-nixie-controller-schematic-pic.jpg
I have several questions for anyone who has successfully used this controller with the above tubes:
1. I need a simple schematic showing how to substitute the DS/DM8880s for the 74141s.
2. Is there a way to eliminate the DS/DM8880 for the Tens of hours tube since this requires only a leading zero blank or a number one for 12 hour mode which is what I will be using. e.g. a MPSA 42 and tie two pins for the cathode segments to make a one?
3. The DS/DM8880 has a Blanking Input that provides unconditional blanking of any
output display, while the Ripple Blanking pins allow simple
leading- or trailing-zero blanking. How is this interfaced with the controller to achieve the night time tube off feature and for leading zero blanking?
4. If the blanking will not work with the DS/DM8880, is it possible to use some sort of logic on the BCD lines, an AND gate maybe to make my own individual blanking outputs. The clock controller will by default blank a tube with a BCD "F" / 1111. A schematic would be very helpful since I have limited engineering capabilities.
Thanks much for any help
Dan
westdave
yep i use that chip a lot , you will want to have the 10 hours display fully wired to the seven segment display if you want to use the slot machine effect i use the ds8880 with the sp101 large speery neon displays and the/ B7971
i think i ended up having to put resistors on all the segments, to get it to run the neon even on each segment, i think i used 15k's
2) its easy just change the bcd wires from the 74141 to the ds8880 so A is A /B is B / C is C / D is D that is the wire placement(pin numbers) has changed
always have your handy spec sheets for the 74141 and the ds8880
i had the "f" problem on another clock the one digit kind ,but i dont think you have to worry about it "F" or blanking (did you want to blank the digit so you dont see it count?)hold then display?
the direct drive chip will work ,have fun with the 53 settings it can do a bunch of stuff.
if you do have trouble with the ds8880(but I think not) you will need to move to a cd4511 this has code correct and no "F"
-----Original Message-----
From: DanielK <DKuriloff@AOL.COM>
To: NEONIXIE-L@yahoogroups.com
Sent: Mon, Mar 1, 2010 3:34 pm
Subject: [NEONIXIE-L] Neonixie 6 digit controller using DM8880 decoder drivers and B7971 Nixie tubes
I would like to build a clock using six B7971 Nixie tubes with the Moses Neonixie 6 digit driver. I have enough DS/DM8880 HV BCD decoder drivers.
I uploaded the data sheets for the DS/DM8880 to the Temp files section on this site.
Here is the schematic for the controller
http://www.neonixie.com/store/images/6-digit-nixie-controller-schematic-pic.jpg
I have several questions for anyone who has successfully used this controller with the above tubes:
1. I need a simple schematic showing how to substitute the DS/DM8880s for the 74141s.
2. Is there a way to eliminate the DS/DM8880 for the Tens of hours tube since this requires only a leading zero blank or a number one for 12 hour mode which is what I will be using. e.g. a MPSA 42 and tie two pins for the cathode segments to make a one?
3. The DS/DM8880 has a Blanking Input that provides unconditional blanking of any
output display, while the Ripple Blanking pins allow simple
leading- or trailing-zero blanking. How is this interfaced with the controller to achieve the night time tube off feature and for leading zero blanking?
4. If the blanking will not work with the DS/DM8880, is it possible to use some sort of logic on the BCD lines, an AND gate maybe to make my own individual blanking outputs. The clock controller will by default blank a tube with a BCD "F" / 1111. A schematic would be very helpful since I have limited engineering capabilities.
Thanks much for any help
Dan
[Non-text portions of this message have been removed]
DanielK
Thanks for the info
<<i think i ended up having to put resistors on all the segments, to get it to run
the neon even on each segment, i think i used 15k's>>
What happened when you drove the cathode tube segments from the DS8880 without current limiting resistors???
<<if you do have trouble with the ds8880(but I think not) you will need to move
to a cd4511 this has code correct and no "F">>
The DS8880 is a high voltage decoder driver. I don't think the cd4511 is designed to drive high voltage Nixie tubes?
The DS/DM8880 has a Blanking Input that provides unconditional blanking of
any output display, while the Ripple Blanking pins allow simple
leading- or trailing-zero blanking. How is this interfaced with the controller
to achieve the night time tube off feature and for leading zero blanking?
Thanks
Dan
