74HC181 Datasheet | Philips Semiconductors

FEATURES - Full carry look-ahead for high-speed arithmetic operation on long words - Provides 16 arithmetic operations: add, subtract, pare, double, plus 12 others - Provides all 16 logic operations of two variables: EXCLUSIVE-OR, pare, AND, NAND, NOR, OR plus 10 other logic operations - Output capability: - ICC category: MSI GENERAL DESCRIPTION The 74HC/HCT181 are high-speed Si-gate CMOS devices and are pin patible with low power Schottky TTL (LSTTL). They are specified in pliance with JEDEC standard no. 7A. The 74HC/HCT181 are 4-bit high-speed parallel Arithmetic Logic Units (ALU). Controlled by the four function select inputs (S0 to S3) and the mode control input (M), they can perform all the 16 possible logic operations or 16 different arithmetic operations on active HIGH or active LOW operands (see function table). When the mode control input (M) is HIGH, all internal carries are inhibited and the device3 performs logic operations on the individual bits as listed. When M is LOW, the carries are enabled and the “181” performs arithmetic operations on the two 4-bit words. The “181” incorporates full internal carry look-ahead and provides for either ripple carry between devices using the Cn+4 output, or for carry look-ahead between packages using the carry propagation (P) and carry generate (G) signals. P and G are not affected by carry in. ORDERING INFORMATION TYPE NUMBER 74HC181N3; 74HCT181N3 74HC181N; 74HCT181N 74HC181D; 74HCT181D PACKAGE NAME DIP24 DIP24 SO24 DESCRIPTION plastic dual in-line package; 24 leads (300 mil) plastic dual in-line package; 24 leads (600 mil) plastic small outline package; 24 leads; body width 7.5 mm standard, A=B open drain 74HC/HCT181 When speed requirements are not stringent, it can be used in a simple ripple carry mode by connecting the carry output (Cn+4) signal to the carry input (Cn) of the next unit. For high-speed operation the device is used in conjunction with the “182” carry look-ahead circuit. One carry look-ahead...