onsemi SN74LS38ML1

Overview

SN74LS38ML1 from ON Semiconductor is a quad 2-input NAND buffer with open-collector outputs, designed for level-shifting and wired-AND logic interfacing in TTL systems. It operates at 4.75–5.25 V, delivers 24 mA sink current per output, and exhibits 18–32 ns propagation delay across 0°C to 70°C ambient range. It is used in industrial control bus drivers and legacy system interface translation.

For engineers reviewing the SN74LS38ML1 datasheet, pinout, applications, or equivalent options, key selection criteria include guaranteed open-collector drive strength (24 mA), input voltage thresholds (VIH = 2.0 V, VIL = 0.8 V), DC/AC timing compliance over temperature, and SOEIAJ-14 package compatibility with legacy board layouts.

Technical Context

The SN74LS38ML1 implements four independent 2-input NAND gates, each with an open-collector output stage enabling wired-logic connections and voltage-level translation. Its Schottky-clamped TTL architecture ensures fast switching and noise immunity while maintaining standard LS power consumption.

It requires external pull-up resistors on all outputs to define HIGH-state voltage levels and supports fan-out to multiple TTL or CMOS inputs. Input clamp diodes (VIK = –0.65 V to –1.5 V) protect against negative transients, and its guaranteed VOL ≤ 0.4 V at IOL = 12 mA ensures reliable LOW-level signaling.

Key Specifications

Pinout & Package

SN74LS38ML1 is housed in a 14-pin SOEIAJ (Small Outline EIAJ) plastic package (Case 965), compliant with JEDEC MS-012 standards. The package features gull-wing leads, 1.27 mm pitch, and dimensions of 8.55 × 3.80 × 1.75 mm (L × W × H).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NAND buffer applications.

Compared with SN74LS38ML1, SN74LS00N lacks open-collector outputs and drive strength, limiting interface flexibility; SN74LS10N changes gate count and topology entirely, requiring logic redesign - neither offers functional equivalence without circuit modification.

Availability

SN74LS38ML1 is available at Aetrix Electronics and suitable for industrial bus interface, legacy system level-shifting, and LED driver interface applications requiring stable component supply and long-term obsolescence mitigation.

Supply support for SN74LS38ML1 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

ON Semiconductor (now part of onsemi) is a global semiconductor supplier specializing in energy-efficient power, analog, sensor, and logic solutions for automotive, industrial, and communications markets.

The SN74LS38ML1 belongs to the classic 74LS logic family, engineered for reliability and interoperability in legacy TTL-based systems where backward compatibility, predictable timing, and robust noise immunity are critical.

FAQ

What is the output configuration of the SN74LS38ML1?

The SN74LS38ML1 features four independent open-collector outputs. This means each output can only actively pull down to GND and requires an external pull-up resistor to establish a HIGH logic level. This configuration enables wired-AND logic, voltage-level translation, and direct driving of loads like LEDs or relays. The SN74LS38ML1 does not provide active HIGH drive capability on any output pin.

Does the SN74LS38ML1 support operation at 3.3 V supply?

No, the SN74LS38ML1 is specified only for 4.75 V to 5.25 V operation. Its internal TTL circuitry requires this voltage range to meet guaranteed VIH (2.0 V), VOL (≤0.4 V), and IOL (24 mA) specifications. Operating at 3.3 V may result in marginal or non-functional behavior, including insufficient noise margin and undefined output states. The SN74LS38ML1 must be used with a regulated 5 V supply.

What is the maximum capacitive load the SN74LS38ML1 can drive reliably?

The SN74LS38ML1 is characterized with CL = 45 pF in AC testing, and its propagation delays (tPLH/tPHL) are guaranteed under that condition. While it can drive higher capacitance, performance degrades linearly: for every 10 pF increase beyond 45 pF, expect ~2–3 ns additional delay. For loads >100 pF, consider adding a buffer stage. The SN74LS38ML1's 24 mA sink strength helps overcome capacitive loading but does not eliminate RC time constant limitations.

Can the SN74LS38ML1 replace SN74LS00 in existing designs?

The SN74LS38ML1 can replace SN74LS00 only if open-collector functionality and higher sink current (24 mA vs. 8 mA) are acceptable or beneficial - and only with modifications: external pull-up resistors must be added to all four outputs, and logic equations must account for active-low wired-AND behavior. Without those changes, the SN74LS38ML1 will not function correctly in a direct SN74LS00 socket. The SN74LS38ML1 is not a drop-in replacement.

Is the SN74LS38ML1 RoHS compliant?

Yes, the SN74LS38ML1 manufactured by Rochester Electronics under license from ON Semiconductor meets RoHS Directive 2011/65/EU requirements. It contains no lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls (PBB), or polybrominated diphenyl ethers (PBDE) above threshold limits. Compliance documentation is available upon request for the specific lot number of SN74LS38ML1 supplied.