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74HC283
4-bit binary full adder with fast carry
Rev. 03 — 11 November 2004
Product data sheet
1. General description
The 74HC283 is a high-speed Si-gate CMOS device and is pin compatible with low power Schottky TTL (LSTTL). The 74HC283 is specified in compliance with JEDEC standard no. 7A.
The 74HC283 adds two 4-bit binary words (An plus Bn) plus the incoming carry (CIN). The binary sum appears on the sum outputs (S1 to S4) and the out-going carry (COUT) according to the equation:
CIN + (A1 + B1) + 2(A2 + B2) + 4(A3 + B3) + 8(A4 + B4) = = S1 + 2S2 + 4S3 + 8S4 + 16COUT
Where (+) = plus.
Due to the symmetry of the binary add function, the 74HC283 can be used with either all active HIGH operands (positive logic) or all active LOW operands (negative logic).