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SN54/74LS247
SN54/74LS248
BCD-TO-SEVEN-SEGMENT SN54/74LS249
DECODERS/DRIVERS
The SN54/74LS247 thru SN54/74LS249 are BCD-to-Seven-Segment
Decoder/Drivers. BCD-TO-SEVEN-SEGMENT
The LS247 and LS248 are functionally and electrically identical to the LS47 DECODERS/ DRIVERS
and LS48 with the same pinout configuration. The LS249 is a 16-pin version LOW POWER SCHOTTKY
of the 14-pin LS49 and includes full functional capability for lamp test and
ripple blanking which was not available in the LS49.
The composition of all characters, except the 6 and 9 are identical between
the LS247, 248, 249 and the LS47, 48 and 49. The LS47 thru 49 compose
the and without tails, the LS247 thru 249 compose the and with
the tails. The LS247 has active-low outputs for direct drive of indicators. The J SUFFIX
LS248 and 249 have active-high outputs for driving lamp buffers. CERAMIC
All types feature a lamp test input and have full ripple-blanking input/output CASE 620-09
controls. On all types an automatic leading and/or trailing-edge zero-blanking 16
1
control (RBI and RBO) is incorporated and an overriding blanking input (BI)
is contained which may be used to control the lamp intensity by pulsing or to
inhibit the output's lamp test may be performed at any time when the BI/RBO N SUFFIX
node is at high level. Segment identification and resultant displays are shown PLASTIC
below. Display pattern for BCD input counts above 9 are unique symbols to CASE 648-08
16
authenticate input conditions.
1
LS247