SN74LS240NSR

SN74LS240NSR is an octal buffer/line driver in the 74LS TTL family with 3-state outputs. It provides eight data lines (A0–A7 to Y0–Y7) across two 4-bit buffer sections and has two independent active-low enables (/G1, /G2). When a /G input is low, the corresponding 4 outputs drive the inputs; when high, those outputs go high-impedance for bus sharing. It operates at a 5V supply (TTL-compatible) and offers the usual LS TTL input thresholds with modest drive on each output. Typical uses include buffering a data bus, isolating devices on a common bus, or level‑buffering between TTL devices. The NSR suffix denotes a specific TI packaging variant (check datasheet for exact pinout and package details). Pinout generally includes A0–A7 inputs, Y0–Y7 outputs, and two enables.

Equivalents (octal buffer/driver with 3-state outputs):
- MC74LS240 (ON Semiconductor)
- 74LS240 / 74LS240N (TTL clones from other vendors)
- CMOS-like substitutes (pin-compatible but with different thresholds): 74HC240, 74HCT240, 74ACT240, 74ALS240 (check voltage requirements and I/O levels)
Note: These are functionally equivalent families; exact pinout and voltage specs should be verified in datasheets for your board.

Here are concise features of SN74LS240NSR:
- Octal buffer/driver with 3-state outputs
- Two 4-bit buffers: A1–A4 to Y1–Y4 and A5–A8 to Y5–Y8
- Non-inverting data path
- TTL-compatible inputs; operates from a single +5V supply
- LS TTL technology (low power)
- Active-low output enables: 1OE and 2OE; outputs go high-impedance when disabled
- Suitable for buffering and isolating data on buses and interfacing TTL devices
- Available in 20-pin NSR package (DIP/SOIC variants)

- Pin count: 20 pins (DIP-20; NSR variant in a similar 20-pin package).
- Function: Octal buffer/line driver with 3-state outputs. It consists of two 4-bit buffers (A0–A7 to Y0–Y7) with independent, active-low enable inputs (1OE and 2OE) that tri-state the outputs when asserted.

- Manufacturer: Texas Instruments (TI)
- What kind of company: American multinational semiconductor company that designs and manufactures analog and digital ICs and other electronics; one of the world’s largest semiconductor producers, based in Dallas, Texas.

SN74LS240NSR is an 8-bit buffer/line driver with two 4-bit sections and 3-state outputs (two enables). Typical applications:
- Microprocessor/memory and I/O bus buffering and isolation (data and address lines)
- Shared bus/backplane interfaces to prevent contention (tri-state when disabled)
- Fan-out expansion and signal conditioning in TTL digital systems
- Interfacing CPUs/controllers to slower peripherals or memory with appropriate drive strength
- General-purpose digital buffering/protection for sensitive devices in digital circuits
(Packaging NSR is a standard DIP for easy PCB integration.)

It comes in a 20-pin plastic DIP package (DIP-20).