MAX6852
Detailed Description
Overview of the MAX6852
The MAX6852 VFD controller generates the multiplex
timing for the following VFD display types:
• Multiplexed displays with one digit per grid, and up
to 48 grids (in 48/1 mode). Each grid can contain
one 5 x 7 matrix character, a decimal place (DP)
segment, a cursor segment, and four extra annunci-
ator segments (Figure 1).
• Multiplexed displays with two digits per grid, and up
to 48 grids (in 96/2 mode). Each grid can contain
two 5 x 7 matrix characters, two DP segments, and
two cursor segments. No annunciator segments are
supported (Figure 2).
Each digit can have a 5 x 7 matrix character, a DP seg-
ment, a cursor segment, and (for one-digit-per-grid dis-
plays only) four annunciators (Figure 3).
The 5 x 7 matrix character segments are not controlled
directly, but use on-chip fonts that map the segments.
The fonts comprise an ASCII 104-character fixed-font
set, and 24 user-definable characters. The predefined
characters follow the Arial font, with the addition of the
following common symbols: £, €, ¥, °, µ, ±, ↑, and ↓.
The 24 user-definable characters are uploaded by the
user into on-chip RAM through the serial interface and
are lost when the device is powered down. As well as
custom 5 x 7 characters, the user-definable fonts can
control up to 35 custom segments, bar graphs, or
graphics.
Annunciator segments have individual, independent
control, so any combination of annunciators can be lit.
Annunciators can be off, lit, or blink either in phase or
out of phase with the cursor. The blink-speed control is
software selectable to be one or two blinks per second
(OSC = 4MHz).
DP segments can be lit or off, but have no blink control.
A DP segment is set by the same command that writes
the digit’s 5 x 7 matrix character.
4-Wire Interfaced, 5
✕
7 Matrix Vacuum-
Fluorescent Display Controller
6 _______________________________________________________________________________________
Pin Description (continued)
