Texas Instruments SN74LS07DR

Overview

SN74LS07DR from Texas Instruments is a hex buffer/driver IC with six independent open-collector outputs, designed for level translation between TTL and higher-voltage circuits (up to 30 V), delivering up to 40 mA sink current per channel, and operating at 5 V supply with 12 ns typical propagation delay. It is used in industrial control I/O interfacing, LED/relay driving, and mixed-voltage logic bridging.

For engineers reviewing the SN74LS07DR datasheet, SN74LS07DR pinout, SN74LS07DR application, or SN74LS07DR equivalent, key selection criteria include open-collector output voltage rating (30 V), sink-current capability (40 mA), input overvoltage tolerance (5.25 V), propagation delay (12 ns), and SOIC-14 package compatibility with legacy TTL systems.

Technical Context

The SN74LS07DR implements six identical inverting buffer stages, each with an open-collector NPN output stage capable of sinking up to 40 mA while tolerating up to 30 V on the output node. Inputs are diode-clamped and rated for 5.25 V, enabling safe interfacing with 3.3-V or 5-V logic sources.

Its logic function is active-low: low input yields low output (sinking), high input yields high-impedance (Hi-Z) output - enabling wired-AND/wired-OR configurations. It requires external pull-up resistors and is not compatible with bus-hold or push-pull loads without additional circuitry.

Key Specifications

Pinout & Package

SN74LS07DR is housed in a 14-pin SOIC (Small Outline Integrated Circuit) package measuring 8.65 mm × 3.90 mm, with 1.27 mm lead pitch and 1.75 mm maximum height. The package is RoHS-compliant, lead-finished with NiPdAu, and rated MSL Level-1 (unlimited floor life at ≤30 °C / 60% RH).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SN74LS07DR, SN74LS06DR offers identical performance and drop-in compatibility, while 74HC07PW trades TTL input compatibility for lower static power and broader supply flexibility - making it suitable only in greenfield CMOS-centric designs.

Availability

SN74LS07DR is available at Aetrix Electronics and suitable for industrial control I/O expansion, LED/indicator lamp driving, relay & solenoid interface, and mixed-voltage logic bridging requiring stable component supply and long-term obsolescence management.

Supply support for SN74LS07DR 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

Texas Instruments is a global semiconductor company founded in 1930, specializing in analog, embedded processing, and logic ICs with broad industrial, automotive, and communications portfolio coverage.

The SN74LS07DR belongs to TI's legacy 74LS logic family, engineered specifically for robust, low-cost interfacing between standard TTL systems and higher-voltage industrial loads - emphasizing reliability, noise immunity, and ease of integration in legacy designs.

FAQ

What is the maximum output voltage rating for SN74LS07DR?

The SN74LS07DR is rated for a maximum output voltage of 30 V. This specification applies to the open-collector output pins (1Y–6Y) when in the high-impedance (Hi-Z) state. Exceeding this voltage risks permanent damage to the output transistor junction. The rating is confirmed in Section 6.1 (Absolute Maximum Ratings) of the official TI datasheet SDLS021D.

Can SN74LS07DR drive multiple TTL inputs directly?

Yes, SN74LS07DR can drive multiple TTL inputs directly due to its 40 mA sink-current capability per output and compatible input thresholds (VIH = 2.0 V, VIL = 0.8 V). Each output can sink the combined input current of up to 10 standard 74LS inputs (each drawing ~0.4 mA low), as verified in TI's Electrical Characteristics table (Section 6.5) and Application and Implementation section (Section 9).

Does SN74LS07DR require external pull-up resistors on its outputs?

Yes, SN74LS07DR requires external pull-up resistors on all six open-collector outputs (1Y–6Y) to establish a defined logic-high voltage level. Without pull-ups, outputs remain floating in the Hi-Z state and cannot assert a high signal. Recommended values range from 1 kΩ to 10 kΩ depending on load capacitance and speed requirements, per TI's Load Circuit guidance in Figure 2.

Is SN74LS07DR compatible with 3.3-V logic inputs?

Yes, SN74LS07DR accepts 3.3-V logic inputs safely. Its inputs are overvoltage-tolerant up to 5.25 V (Section 8.3 Feature Description), and its VIH threshold is 2.0 V minimum - well below 3.3 V. This allows direct connection to LVTTL or 3.3-V MCU GPIOs without level shifters, as confirmed in the Recommended Operating Conditions table (Section 6.3).

What is the thermal resistance (RθJA) of SN74LS07DR in its SOIC package?

The junction-to-ambient thermal resistance (RθJA) for SN74LS07DR in the SOIC (D) package is 85.2 °C/W, as specified in Section 6.4 (Thermal Information) of the TI datasheet. This value assumes standard JEDEC 2-layer board conditions and is critical for calculating maximum power dissipation (140 mW typical) under worst-case ambient temperatures (70 °C).