Hi all, I am searching for a driver for 6-8 digits of 5x7 LED matrix displays. All I can find seems to be the 4-digit MAX6952/3 chips. Two of these would ofcourse work, but that requires a lot of space and they are not cheap either. I do not really need all the font functionality etc. As long as I can control each LED seperately, I'm OK. Another option would be a chip with only the drive transistors and current sources and do the multiplexing in SW. Does anybody know of chips that might do the job or manufacturers that carry these things? Or does anybody know of 30mm 5x7 displays with integrated drivers? All I have found are 5mm and 7mm, 4 or 8 digits (and with this option I need 6 digits). Preferably these displays should be available in red and blue. TIA, -- Stef (remove caps, dashes and .invalid from e-mail address to reply) Laugh at your problems; everybody else does.
Searching for 8-digit 5*7 LED matrix display driver
Started by ●June 11, 2004
Reply by ●June 12, 20042004-06-12
Stef wrote:> Hi all, > > I am searching for a driver for 6-8 digits of 5x7 LED matrix displays. > All I can find seems to be the 4-digit MAX6952/3 chips. Two of these > would ofcourse work, but that requires a lot of space and they are not > cheap either. I do not really need all the font functionality etc. As > long as I can control each LED seperately, I'm OK. Another option would > be a chip with only the drive transistors and current sources and do > the multiplexing in SW. > > Does anybody know of chips that might do the job or manufacturers that > carry these things? > > Or does anybody know of 30mm 5x7 displays with integrated drivers? All > I have found are 5mm and 7mm, 4 or 8 digits (and with this option I > need 6 digits). Preferably these displays should be available in red > and blue. > > > TIA, >Maxim makes 8 digit display driver chips. Do a search on MAX7219 or click on the link below: http://www.maxim-ic.com/quick_view2.cfm?qv_pk=1339 Other chips that you may want to consider are: MAX6591, ICM7218, ICM7228, MAX7221. Good luck on your search. Mostafa
Reply by ●June 12, 20042004-06-12
On Sat, 12 Jun 2004 13:29:51 GMT, Mostafa Kassem <No_one@Nowhere.com> wrote:>Stef wrote: >> Hi all, >> >> I am searching for a driver for 6-8 digits of 5x7 LED matrix displays. >> All I can find seems to be the 4-digit MAX6952/3 chips. Two of these >> would ofcourse work, but that requires a lot of space and they are not >> cheap either. I do not really need all the font functionality etc. As >> long as I can control each LED seperately, I'm OK. Another option would >> be a chip with only the drive transistors and current sources and do >> the multiplexing in SW. >> >> Does anybody know of chips that might do the job or manufacturers that >> carry these things? >> >> Or does anybody know of 30mm 5x7 displays with integrated drivers? All >> I have found are 5mm and 7mm, 4 or 8 digits (and with this option I >> need 6 digits). Preferably these displays should be available in red >> and blue.Probably the cheapest way would be to use a string of 74HC595s as column drivers and transistors (maybe driven from a HC138 if I/O is tight) as row drivers, and use a timer interrupt task to keep them refreshed. If CPU usage or IO is tight, you could use a seperate cheap MCU, e.g. PIC as a display controller to do the refresh & character generation and send it the characters serially. A PIC16F627 at <$2 could do it easily.
Reply by ●June 13, 20042004-06-13
oN 11-Jun-04, Stef said:> I am searching for a driver for 6-8 digits of 5x7 LED matrix displays.You may want to look here: http://www.allegromicro.com/ic/leddriver.asp -- Bill Posted with XanaNews Version 1.16.3.1
Reply by ●June 14, 20042004-06-14
In comp.arch.embedded, Mostafa Kassem <No_one@Nowhere.com> wrote:>Stef wrote: >> Hi all, >> >> I am searching for a driver for 6-8 digits of 5x7 LED matrix displays. >> All I can find seems to be the 4-digit MAX6952/3 chips. Two of these >> would ofcourse work, but that requires a lot of space and they are not >> cheap either. I do not really need all the font functionality etc. As >> long as I can control each LED seperately, I'm OK. Another option would >> be a chip with only the drive transistors and current sources and do >> the multiplexing in SW. >> > >Maxim makes 8 digit display driver chips. Do a search on MAX7219 or click >on the link below: > >Other chips that you may want to consider are: MAX6591, ICM7218, ICM7228, >MAX7221.^^^^^^^ MAX6951 ?? These are all 7-segment display drivers, driving at most 64 LED's. I am looking for 8-digit, 5x7 matrix display drivers, driving 280 LED's. -- Stef (remove caps, dashes and .invalid from e-mail address to reply) It's no surprise that things are so screwed up: everyone that knows how to run a government is either driving taxicabs or cutting hair. -- George Burns
Reply by ●June 14, 20042004-06-14
In comp.arch.embedded, Mike Harrison <mike@whitewing.co.uk> wrote:>On Sat, 12 Jun 2004 13:29:51 GMT, Mostafa Kassem <No_one@Nowhere.com> wrote: > >>Stef wrote: >>> Hi all, >>> >>> I am searching for a driver for 6-8 digits of 5x7 LED matrix displays. >>> All I can find seems to be the 4-digit MAX6952/3 chips. Two of these >>> would ofcourse work, but that requires a lot of space and they are not >>> cheap either. I do not really need all the font functionality etc. As >>> long as I can control each LED seperately, I'm OK. Another option would >>> be a chip with only the drive transistors and current sources and do >>> the multiplexing in SW. >>> >Probably the cheapest way would be to use a string of 74HC595s as column drivers and transistors >(maybe driven from a HC138 if I/O is tight) as row drivers, and use a timer interrupt task to keep >them refreshed.Yes, this is an option, but the drive capability of the 74HC595 may be a bit on the low side and I may need to add a current source somewhere.>If CPU usage or IO is tight, you could use a seperate cheap MCU, e.g. PIC as a display controller to >do the refresh & character generation and send it the characters serially. A PIC16F627 at <$2 could >do it easily. >-- Stef (remove caps, dashes and .invalid from e-mail address to reply) Lost: gray and white female cat. Answers to electric can opener.
Reply by ●June 14, 20042004-06-14
In comp.arch.embedded, William Meyer <wmeyerNO@SPAMsbcglobal.net> wrote:>oN 11-Jun-04, Stef said: > >> I am searching for a driver for 6-8 digits of 5x7 LED matrix displays. > >You may want to look here: >http://www.allegromicro.com/ic/leddriver.asp >These look interesting, but no single or low package count solution. So I'll look a bit further but keep these in mind. -- Stef (remove caps, dashes and .invalid from e-mail address to reply) Justice always prevails ... three times out of seven! -- Michael J. Wagner
Reply by ●June 14, 20042004-06-14
On Fri, 11 Jun 2004 15:42:08 +0200, stef33d@yahooI-N-V-A-L-I-D.com.invalid (Stef) wrote:>Hi all, > >I am searching for a driver for 6-8 digits of 5x7 LED matrix displays. >All I can find seems to be the 4-digit MAX6952/3 chips. Two of these >would ofcourse work, but that requires a lot of space and they are not >cheap either. I do not really need all the font functionality etc. As >long as I can control each LED seperately, I'm OK. Another option would >be a chip with only the drive transistors and current sources and do >the multiplexing in SW. > >Does anybody know of chips that might do the job or manufacturers that >carry these things? > >Or does anybody know of 30mm 5x7 displays with integrated drivers? All >I have found are 5mm and 7mm, 4 or 8 digits (and with this option I >need 6 digits). Preferably these displays should be available in red >and blue. > > >TIA,These aren't cheap either, and not 5 x 7, but they're available in green and red. Cascadeable 8 x 8 dot matrix LED module. Compatible with SPI, QSPI and Microwire. http://www.nexusmachines.com/Products/displays/bxxcdm.htm
Reply by ●June 14, 20042004-06-14
On Fri, 11 Jun 2004 15:42:08 +0200, stef33d@yahooI-N-V-A-L-I-D.com.invalid (Stef) wrote:>Hi all, > >I am searching for a driver for 6-8 digits of 5x7 LED matrix displays. >All I can find seems to be the 4-digit MAX6952/3 chips. Two of these >would ofcourse work, but that requires a lot of space and they are not >cheap either. I do not really need all the font functionality etc. As >long as I can control each LED seperately, I'm OK. Another option would >be a chip with only the drive transistors and current sources and do >the multiplexing in SW. > >Does anybody know of chips that might do the job or manufacturers that >carry these things? > >Or does anybody know of 30mm 5x7 displays with integrated drivers? All >I have found are 5mm and 7mm, 4 or 8 digits (and with this option I >need 6 digits). Preferably these displays should be available in red >and blue. > > >TIA,Then again there's TI's TLC5920, a 16 x 8 LED driver. $2.90 ea 1K+. Samples are available. If you wish to drive the rows and columns with seperate ICs, then you can drive the columns with a TI TPIC6595 8-bit serial shift register which has power DMOS switches.
Reply by ●June 14, 20042004-06-14
On Mon, 14 Jun 2004 22:35:07 +1000, the renowned dmm!@work.now wrote:>On Fri, 11 Jun 2004 15:42:08 +0200, stef33d@yahooI-N-V-A-L-I-D.com.invalid (Stef) wrote: > >>Hi all, >> >>I am searching for a driver for 6-8 digits of 5x7 LED matrix displays. >>All I can find seems to be the 4-digit MAX6952/3 chips. Two of these >>would ofcourse work, but that requires a lot of space and they are not >>cheap either. I do not really need all the font functionality etc. As >>long as I can control each LED seperately, I'm OK. Another option would >>be a chip with only the drive transistors and current sources and do >>the multiplexing in SW. >> >>Does anybody know of chips that might do the job or manufacturers that >>carry these things? >> >>Or does anybody know of 30mm 5x7 displays with integrated drivers? All >>I have found are 5mm and 7mm, 4 or 8 digits (and with this option I >>need 6 digits). Preferably these displays should be available in red >>and blue. >> >> >>TIA, > >Then again there's TI's TLC5920, a 16 x 8 LED driver. $2.90 ea 1K+. Samples are available. > >If you wish to drive the rows and columns with seperate ICs, then you can drive the columns >with a TI TPIC6595 8-bit serial shift register which has power DMOS switches.The rows can be driven with 3 dual p-channel MOSFETs. Parts count: 7 xx595s SMT 7 8-resistor arrrays (or 14 quads) SMT 3 dual p-channel MOSFETS SO-8 --- 17/24 parts Not bad. Watch the layout on the grounds for the column drivers and make sure you buy the right "polarity" of display. Best regards, Spehro Pefhany -- "it's the network..." "The Journey is the reward" speff@interlog.com Info for manufacturers: http://www.trexon.com Embedded software/hardware/analog Info for designers: http://www.speff.com
