

pin      function
 1      led supply voltage
 2      latch data input b
 3      latch data input a
 4      left decimal point cathode
 5      latch strobe input
 6      omitted
 7      common gnd
 8      blanking input
 9      omitted
10      right decimal point cathode
11      omitted
12      latch data input d
13      latch data input c
14      logic supply voltage (5v)

LATCH STROBE INPUT, pin 5, when low, the data in the latches follow the data on the latch data
                             inputs.  When high, the data in the latches will not change.  If the
                               display is blanked and then restored while the enable input is high,
                               the previous character will again be displayed.

BLANKING INPUT, pin 8,    When high, the display is blanked regardless of the levels of the other
                              inputs.  When low, a character is displayed as determined by the data
                              in the latches.  The blanking input may be pulsed for intensity modulation.

LATCH DATA INPUTS, pins 2,3,12,13,   Data on these inputs are entered into the latches when the enable
                                          input is low.  The binary weights of these inputs are A = 1,
                                          B = 2, C = 4, D = 8

DECIMAL POINT CATHODES, pins 4, 10,   These LEDS are not connected to the logic chip.  If a decimal point
                                          is used, an external resistor or other current limiting
                                          mechanism must be connected in series with it.

LED SUPPLY, pin 1            This connection permits the user to save on regulated Vcc current by using
                                 a separate LED supply, or it may be externally connected to the logic
                                 supply (Vcc).

LOGIC SUPPLY (Vcc), pin 14      Separate Vcc connection for the logic chip

COMMON GROUND, pin 7,      This is the vegative termnal for all logic and LED currents except for the
                              decimal points.