Summary of Driving 14-segment displays with the MAX6954
This article serves as a quick-start guide for engineers using the MAX6954 display driver to control eight mono-color, 14-segment LEDs. It details the specific connection scheme required to utilize the chip's multiplexing technique and internal 104-character font map, referencing related application notes for 7-segment and 16-segment configurations.
Parts used in Driving 14-Segment Displays with the MAX6954:
- MAX6954 Display Driver
- Eight Mono-Color 14-Segment LEDs
- Serial Interface
- Internal Registers
- 104-Character Font Map
Abstract: This article is how-to guide, intended as a quick learning aid for engineers considering using the MAX6954 to drive 14-segment monocolor LEDs.
The MAX6954 is a versatile display driver, capable of controlling a mix of discrete, 7-segment, 14-segment, and 16-segment LED displays through a serial interface. This application note shows a typical application and configuration for driving eight mono-color, 14-segment LEDs.
See the MAX6954 data sheet for additional information about MAX6954 features.
“Quick-Start: Driving 7-Segment Displays with the MAX6954” and “Quick-Start: Driving 16-Segment Displays with the MAX6954” are similar application notes that discuss configuring the MAX6954 for 7-segment and 16-segment applications, respectively.
Table 1. Connection Scheme for Eight 14-Segment Digits
| DIGIT | O0 | O1 | O2 | O3 | O4 | O5 | O6 | O7 | O8 | O9 | O10 | O11 | O12 | O13 | O14 | O15 | O16 | O17 | O18 |
| 0 | CCO | — | a | — | b | c | d | — | e | f | g1 | g2 | h | i | j | k | l | m | dp |
| 1 | — | CC1 | a | — | b | c | d | — | e | f | g1 | g2 | h | i | j | k | l | m | dp |
| 2 | a | — | CC2 | — | b | c | d | — | e | f | g1 | g2 | h | i | j | k | l | m | dp |
| 3 | a | — | — | CC3 | b | c | d | — | e | f | g1 | g2 | h | i | j | k | l | m | dp |
| 4 | a | — | b | c | CC4 | — | d | — | e | f | g1 | g2 | h | i | j | k | l | m | dp |
| 5 | a | — | b | c | — | CC5 | d | — | e | f | g1 | g2 | h | i | j | k | l | m | dp |
| 6 | a | — | b | c | d | — | CC6 | — | e | f | g1 | g2 | h | i | j | k | l | m | dp |
| 7 | a | — | b | c | d | — | — | CC7 | e | f | g1 | g2 | h | i | j | k | l | m | dp |
A common application for the MAX6954 is driving up to eight 14-segment mono-color LEDs. This application note guides the user through the process of connecting the MAX6954 to 14-segment displays and configuring the internal registers to control the displays using the included 104-character font map.
The MAX6954 utilizes a multiplex technique that reduces driver pin count by using ports alternately as cathode and anode drivers. This differs from the standard LED multiplex connection, which uses separate driver pins for anodes and cathodes. The technique is discussed in AppNote 1880. Table 1 lists the connection scheme for 14-segment digits that is compatible with the MAX6954 multiplex scheme and the built in 104-character font map. The letters in Table 1 correspond to the segment labels shown in Figure 2. Figure 1 illustrates an eight digit, 14-segment application circuit for the MAX6954.
For more detail: Driving 14-segment displays with the MAX6954
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What is the primary function of the MAX6954 described in this article?
The MAX6954 is a versatile display driver capable of controlling discrete, 7-segment, 14-segment, and 16-segment LED displays through a serial interface. -
How does the MAX6954 reduce driver pin count?
It utilizes a multiplex technique that uses ports alternately as cathode and anode drivers instead of using separate pins for each. -
What is the maximum number of 14-segment digits this configuration supports?
This application note guides users on connecting up to eight 14-segment mono-color LEDs. -
Which feature allows the driver to control specific segments easily?
The device uses an internal 104-character font map to control the displays via its internal registers. -
Where can one find information about driving 7-segment displays with this chip?
The article references Quick-Start application notes specifically for driving 7-segment and 16-segment displays. -
Does the connection scheme differ from standard LED multiplex connections?
Yes, the MAX6954 differs by alternating port functions rather than using separate driver pins for anodes and cathodes.
