The 74181 is a 4-bit slice arithmetic logic unit (ALU), implemented as a 7400 series TTL integrated circuit. Introduced by Texas Instruments in February 1970, [1] it was the first complete ALU on a single chip. [2] It was used as the arithmetic/logic core in the CPUs of many historically significant minicomputers and other devices.

But in March 1970, Texas Instruments introduced the 74181 Arithmetic / Logic Unit (ALU) chip, which put a full 4-bit ALU on one fast TTL chip. This chip provided 32 arithmetic and logic functions, as well as carry lookahead for high performance.

Nov 19, 2017 · Registers, instruction decoders, counters, and an arithmetic/logic unit, or ALU. And for decades the 74181, as an all-in-one 4-bit ALU on a chip that you might have found in a minicomputer at the...

The 74181 ALU chip is a complex, high-performance TTL chip that was a key component in the processor of many minicomputers. I took detailed die photos of the 74181 ALU that reveal how the chip works internally.

In today’s material, I will tell you about the construction, history and operation of one of the first ALUs. The main role in today’s story will be played by a chip designated 74181. It is a TTL chip enclosed in a 24-pin housing, first presented to the world in early 1970 by Texas Instruments.

Mar 27, 2017 · One of the more famous of these devices is the 74181, a cascadable 4-bit arithmetic logic unit, or ALU. An ALU is the heart of a microprocessor, performing its operations.

Jan 13, 2017 · The 74181 was a popular chip in the 1970s used to perform calculations in the arithmetic-logic unit (ALU) of minicomputers. It is a moderately complex chip containing about 67 gates and 170 transistors3, implemented using fast …

This applet demonstrates the TTL-series 4-bit 74181 arithmetic-logical unit. It takes 4-bit operands and a carry input and calculates one of 16 logical or 16 arithmetic functions. Two additional active-low outputs X (/propagate) and Y (/generate) allow to interface to the 74182 carry-lookahead generator IC for fast addition.

This applet demonstrates a fast 12-bit ALU built from three 4-bit 74181 ALU chips and one 74182 carry-lookahead generator chip. The internal structure of the 74182 chips is shown in the next applet.

Jan 8, 2017 · Data sheets from RCA, Harris (4-bit CMOS), TI (4-bit TTL), IDT (16-bit CMOS), and many others are freely available. Simply grab yourself some simple gates and plagiarize away. What’s the big deal?