Texas Instruments L293NEG4

Overview

L293NEG4 from Texas Instruments is a quadruple high-current half-H driver IC designed to provide bidirectional drive currents up to 1 A per channel at supply voltages from 4.5 V to 36 V. It features separate logic (VCC1) and motor (VCC2) supplies, TTL-compatible inputs tolerant to 7 V, and internal Darlington/pseudo-Darlington output stages for driving inductive loads such as DC motors, bipolar stepper motors, and relays in industrial motion control systems.

For engineers reviewing the L293NEG4 datasheet, L293NEG4 pinout, L293NEG4 application, or L293NEG4 equivalent, key selection criteria include continuous output current rating (1 A), enable-pair architecture (1,2EN / 3,4EN), thermal resistance (RθJA = 36.4°C/W), and integrated high-noise-immunity input logic - all critical for robust motor interface design in temperature-constrained embedded systems.

Technical Context

The L293NEG4 implements four independent half-H driver channels grouped into two enable-controlled pairs: channels 1–2 activated by 1,2EN and channels 3–4 by 3,4EN. Each channel uses a Darlington transistor sink and pseudo-Darlington source to deliver high-current switching with low saturation voltage (VOL ≤ 1.8 V at 1 A).

It requires dual supplies: VCC1 (4.5–7 V) powers TTL-compatible input logic and translation circuitry, while VCC2 (4.5–36 V) supplies the output drivers. Unlike the L293D variant, the L293NEG4 lacks integrated clamp diodes - external fast-recovery diodes are mandatory for inductive transient suppression in relay or motor applications.

Key Specifications

Pinout & Package

Package: PDIP-16 (19.80 mm × 6.35 mm), through-hole, RoHS-compliant, with pins 4, 5, 12, and 13 internally connected to ground and intended for heatsink attachment via PCB ground plane vias.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar half-H driver applications.

Compared with L293DNE, the L293NEG4 offers 67% higher continuous current but requires external diodes; versus SN754410NE, it has higher thermal resistance and older process technology - making SN754410NE preferable for thermally constrained or long-lifecycle designs.

Availability

L293NEG4 is available at Aetrix Electronics and suitable for DC motor control, bipolar stepper motor drive, latching relay interface, and industrial solenoid actuation requiring stable component supply across production volumes and extended product lifecycles.

Supply support for L293NEG4 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 leader specializing in analog, embedded processing, and connectivity technologies, with over five decades of innovation in power management and motor control ICs.

The L293x family was engineered for cost-effective, discrete-style motor interface solutions in commercial and industrial equipment - prioritizing simplicity, ruggedness, and compatibility with legacy 5 V logic systems.

FAQ

What is the maximum continuous output current per channel for the L293NEG4?

The L293NEG4 supports a continuous output current of 1 A per channel under recommended operating conditions (TA ≤ 70°C, proper heatsinking). This rating assumes adequate PCB copper area or external heatsinking to maintain junction temperature below 150°C. Exceeding this current without thermal mitigation triggers thermal shutdown, temporarily disabling outputs until safe temperature is restored. Always verify actual power dissipation using RθJA = 36.4°C/W and ambient conditions in your L293NEG4 design.

Does the L293NEG4 include integrated flyback diodes for inductive load protection?

No, the L293NEG4 does not integrate output clamp diodes. Unlike the L293DNE variant, it requires external fast-recovery diodes (e.g., SES5001) connected from each Y-output to VCC2 and GND to suppress inductive kickback from motors, relays, or solenoids. Omitting these diodes risks destructive voltage spikes exceeding the absolute maximum VO rating of VCC2 + 3 V. The L293NEG4 datasheet explicitly states that external diodes are mandatory for safe inductive load operation.

Can the L293NEG4 be used to drive a bipolar stepper motor?

Yes, the L293NEG4 is commonly used to drive bipolar stepper motors by configuring its four half-H drivers as two full-H bridges - one for phase A (channels 1–2) and one for phase B (channels 3–4). Enable pins 1,2EN and 3,4EN control each bridge independently, while inputs 1A/2A and 3A/4A determine current direction per winding. Its 1 A per channel rating matches typical NEMA 17 stepper holding currents, and TTL-compatible inputs simplify microcontroller interfacing in L293NEG4-based motion control designs.

What are the required supply voltages for the L293NEG4, and how should they be decoupled?

The L293NEG4 requires two supplies: VCC1 (4.5 V to 7 V) for logic and VCC2 (4.5 V to 36 V) for outputs. VCC1 must be bypassed with ≥0.1 µF ceramic capacitor close to pin 16; VCC2 requires ≥1 µF low-ESR capacitor near pin 8. Both supplies must be well-regulated and low-noise - especially VCC2, which directly impacts output current stability and thermal performance. Avoid sharing VCC1 with noisy digital rails; use dedicated LDO or filtered supply for optimal L293NEG4 noise immunity and timing accuracy.

Is the L293NEG4 pin-compatible with the L293DNE?

Yes, the L293NEG4 and L293DNE share identical PDIP-16 packaging, pin numbering, and pin functions - including 1,2EN, 3,4EN, A/Y signal assignments, and VCC1/VCC2/GND locations. However, they differ electrically: L293NEG4 delivers 1 A continuous current with no internal diodes, while L293DNE provides 600 mA with integrated clamps. Swapping them requires verifying current demand and adding/removing external diodes accordingly - the L293NEG4 is not a drop-in replacement without circuit review.