Renesas 74LS51P-E

Overview

74LS51P-E from Renesas is a dual 2-input and dual 3-input AND-OR-INVERT (AOI) gate logic IC in a 14-pin PDIP package, operating at 4.75–5.25 V, with propagation delays of 12–20 ns and output drive capability of ±400 µA/8 mA. It implements combinational logic for TTL-level digital systems including address decoding and control signal generation.

For engineers reviewing the 74LS51P-E datasheet, 74LS51P-E pinout, 74LS51P-E application, or 74LS51P-E equivalent, key selection criteria include its AOI gate configuration, guaranteed 75°C operation, DIP-14 mechanical compatibility, and verified 15 pF load switching performance under standard TTL conditions.

Technical Context

The 74LS51P-E integrates two independent AOI functions: one 2-wide 2-input gate (inputs 1A–1B, 1C–1D → output 1Y) and one 2-wide 3-input gate (inputs 2A–2B–2C, 2D–2E–2F → output 2Y), each with open-collector outputs requiring external pull-up resistors. Its internal structure uses bipolar TTL transistor logic with Schottky-clamped inputs and outputs.

It complies with standard LS-TTL electrical specifications: VIH ≥ 2.0 V, VIL ≤ 0.8 V, VOH ≥ 2.7 V (at IOH = –400 µA), VOL ≤ 0.4 V (at IOL = 4 mA), and supports operation across –20°C to +75°C ambient temperature with supply current ICCL up to 2.8 mA.

Key Specifications

Pinout & Package

74LS51P-E is housed in a 14-pin plastic dual in-line package (PDIP), designated DILP-14 pin (RENESAS code PRDP0014AB-B), with 2.54 mm pitch, 19.2 mm length, 6.3 mm width, and 3.3 mm height. Pin 1 is top-left corner with notch orientation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar AND-OR-INVERT logic applications.

Compared with SN74LS51N and MC74LS51PG, the 74LS51P-E offers identical AOI logic, DIP-14 mechanical fit, and LS-TTL interface behavior - enabling drop-in substitution where Renesas-sourced components are specified for long-term availability or regional logistics alignment.

Availability

74LS51P-E is available at Aetrix Electronics and suitable for industrial control panels, legacy microprocessor system upgrades, and test equipment refurbishment requiring stable component supply over extended production lifecycles.

Supply support for 74LS51P-E includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Renesas Electronics Corporation is a global semiconductor leader specializing in microcontrollers, analog, power, and mixed-signal solutions for automotive, industrial, and infrastructure markets.

The 74LS51P-E belongs to Renesas' legacy TTL logic family designed for backward compatibility, reliability in harsh environments, and seamless integration into established 5 V digital systems.

FAQ

What logic functions does the 74LS51P-E implement?

The 74LS51P-E implements two independent AND-OR-INVERT (AOI) functions: one 2-wide 2-input gate (1A–1B and 1C–1D → 1Y) and one 2-wide 3-input gate (2A–2B–2C and 2D–2E–2F → 2Y). Both outputs are open-collector, requiring external pull-up resistors. This configuration enables efficient sum-of-products logic synthesis in fixed-function digital circuits without additional gates.

Is the 74LS51P-E pin-compatible with other 74LS51 variants?

Yes, the 74LS51P-E shares identical pinout and electrical specifications with industry-standard 74LS51 devices including SN74LS51N and MC74LS51PG. All use the same 14-pin DIP layout, input/output assignments, and LS-TTL voltage thresholds, enabling direct physical and functional replacement in existing PCBs designed for the 74LS51 logic family.

Does the 74LS51P-E require external pull-up resistors on its outputs?

Yes, the 74LS51P-E features open-collector outputs (1Y and 2Y), meaning they can only sink current and cannot source it. External pull-up resistors to VCC (or another logic-high voltage) are mandatory to establish valid HIGH logic levels. Typical values range from 1.0 kΩ to 10 kΩ depending on capacitive load and speed requirements.

What is the maximum operating temperature for the 74LS51P-E?

The 74LS51P-E is rated for operation from –20°C to +75°C ambient temperature, as confirmed in the Recommended Operating Conditions table of its official datasheet (Rev. 3.00, Jul. 22, 2005). This range supports deployment in industrial control cabinets and non-temperature-controlled instrumentation environments without derating.

Can the 74LS51P-E be used in place of discrete 74LS00 and 74LS32 combinations?

Yes, the 74LS51P-E replaces common combinations like 74LS00 (NAND) + 74LS32 (OR) to implement AOI logic more efficiently. Its integrated structure reduces board space, interconnect delay, and component count while preserving LS-TTL timing and drive characteristics - making it ideal for consolidating logic in legacy 5 V systems.