Multiple Seven Segment Displays

[polus]

multiple seven segment

I have a project that requires 12 of these. Has anyone used this many in a project before and whats the cheapest/best way of controlling them all?

Presumably Id need a port (8 bits) for the different LED's within the displays and then 12 display select lines? But how to keep state?

I have found an alternative in the fiorm of the MAX6955 which looks like a great IC and will allow the use of a cheaper MCU (with less IO) but the MAX IC is expensive.

MAX6955 Datasheet:
**broken link removed**

Any tips or pointers would be very much appreciated!

 

[sunish]

multiple seven segment displays

hai
there are manyoptions
you can simply use an 8051 where u will get 4 ports(4x8)
out of which one port can be used for data out put
and any 12 lines can be used for switching the displays
this can be done by using transistors for each display and make
them on/off according to the data on which display to be displayed
u can also use de multiplexer ic's but if one part of the display is gone wrong,
u have to change the entire ic
so the cheap way is using transistors


regards


sun

 

[cristianp]

max6955

You can find an application note with 4x 7LED display at the following link: http://www.atmel.com/dyn/resources/prod_documents/doc1231.pdf. For more digits you can use a demultiplexer or a serial to paralel register (74HC595) to control each digit.

 

[polymath]

multiple seven segment display

Hi polus

You could try MAX7221CNG - 7 segment, 8 digits, SPI comms, brightness & digit control

**broken link removed**

regards ... Polymath