The SN54S182 and SN74S182 are high-speed, look-ahead carry generators capable
of anticipating a carry across four binary adders or group of adders. They
are cascadable to perform full look-ahead across n-bit adders. Carry, generate-carry,
and propagate-carry functions are provided as enumerated in the pin designation
table above.
When used in conjunction with the 'LS181 or 'S181 arithmetic logic unit
(ALU), these generators provide high-speed carry look-ahead capability for
any word length. Each 'S182 generates the look-ahead (anticipated carry) across
a group of four ALUs and, in addition, other carry look-ahead circuits may
be employed to anticipate carry across sections of four look-ahead packages
up to n-bits. The method of cascading 'S182 circuits to perform multilevel
look-ahead is illustrated under typical application data.
The carry functions (inputs, outputs, generate, and propagate) of the look-ahead
generators are implemented in the compatible forms for direct connection to
the ALU. Reinterpretations of carry functions as explained on the 'LS181 and
'S181 data sheet are also applicable to and compatible with the look-ahead
generator. Logic equations for the 'S182 are:
The SN54S182 and SN74S182 are high-speed, look-ahead carry generators capable
of anticipating a carry across four binary adders or group of adders. They
are cascadable to perform full look-ahead across n-bit adders. Carry, generate-carry,
and propagate-carry functions are provided as enumerated in the pin designation
table above.
When used in conjunction with the 'LS181 or 'S181 arithmetic logic unit
(ALU), these generators provide high-speed carry look-ahead capability for
any word length. Each 'S182 generates the look-ahead (anticipated carry) across
a group of four ALUs and, in addition, other carry look-ahead circuits may
be employed to anticipate carry across sections of four look-ahead packages
up to n-bits. The method of cascading 'S182 circuits to perform multilevel
look-ahead is illustrated under typical application data.
The carry functions (inputs, outputs, generate, and propagate) of the look-ahead
generators are implemented in the compatible forms for direct connection to
the ALU. Reinterpretations of carry functions as explained on the 'LS181 and
'S181 data sheet are also applicable to and compatible with the look-ahead
generator. Logic equations for the 'S182 are: