STMicroelectronics L292

Overview

L292 from STMicroelectronics is a monolithic H-bridge switch-mode motor driver IC in Multiwatt15 package, designed as the final-stage power driver in a 3-chip microprocessor-controlled positioning system for DC motors. It delivers ±2 A continuous output current at up to 36 V supply, operates with 1–30 kHz PWM switching frequency, features dual logic-controlled enable inputs (pins 12 and 13), and includes thermal protection and internal current sensing with external loop gain adjustment.

For engineers reviewing the L292 datasheet, L292 pinout, L292 application, or L292 equivalent, this page provides verified technical context for carriage/daisy-wheel position control systems, closed-loop motor current regulation, single-supply operation (18–36 V), and integration with L290 tachometer and L291 DAC chips in legacy typewriter positioning designs.

Technical Context

The L292 implements a bidirectional H-bridge with internal current-sense amplifiers (Rs1/Rs2 = 0.2 Ω typical), error amplifier input (pin 6), and triangle-wave oscillator (pins 10–11) for PWM generation. Its transconductance is 220 mA/V (typ.) with 0.44 V max sensing voltage at 2 A output.

Control architecture relies on external RC networks for loop compensation (pins 5, 7, 9), programmable dead-time via C17 (≈1.5 nF for 2.5 µs), and dual active-high/active-low enable logic (pins 12/13) compatible with microprocessor reset timing. The device operates only above 18 V supply and disables output below that threshold.

Key Specifications

Pinout & Package

Package: Multiwatt15 vertical through-hole package with integrated heat slug (mechanical outline per STMicroelectronics drawing, 22.2 mm length, 17.78 mm width, 4.55 mm height).

Key Features

Applications

Equivalent & Alternatives

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

Compared with L292, both L293D and SN754410 lack integrated current sensing, programmable PWM oscillation, dual enable logic, and thermal shutdown-making them unsuitable for closed-loop positioning systems requiring ±2 A drive and microprocessor-coordinated timing.

Availability

L292 is available at Aetrix Electronics and suitable for legacy printer repair, electromechanical typewriter restoration, optical encoder-based servo retrofitting, and industrial motion control continuity programs requiring stable component supply.

Supply support for L292 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in automotive, industrial, and power management ICs with broad manufacturing and quality certification coverage.

The L292 belongs to ST's legacy motor driver product line, engineered specifically for microprocessor-coordinated, high-accuracy DC motor positioning in electromechanical office equipment of the 1980s–1990s era.

FAQ

What is the minimum supply voltage required for L292 operation?

The L292 requires a minimum supply voltage of 18 V to operate; output stage inhibition occurs automatically if Vs falls below this threshold. This undervoltage lockout protects against erratic switching and ensures stable H-bridge biasing across the specified 18–36 V range.

Can L292 be used without the L290 and L291 chips?

Yes, the L292 can be used independently as a standalone H-bridge driver with external PWM and current feedback. However, its internal error amplifier, oscillator, and enable logic are optimized for integration with L290/L291 in closed-loop positioning systems-not generic motor control.

What is the purpose of the dual enable inputs (pins 12 and 13)?

Pins 12 (active-low) and 13 (active-high) provide flexible microprocessor interface timing: pin 12 handles reset-induced spikes (<1.5 V), while pin 13 supports clean logic-level activation. Either pin can disable the output, preventing shoot-through during power-up or system reset.

How is dead-time controlled in the L292 H-bridge?

Dead-time is set by capacitor C17 connected to pin 10, interacting with an internal ~1.5 kΩ resistor (Rτ). With C17 ≈ 1.5 nF, τ = Rτ·C17 yields ~2.5 µs delay-sufficient to prevent simultaneous conduction of high- and low-side transistors in the H-bridge output stage.