Texas Instruments LM393PSR

Overview

LM393PSR from Texas Instruments is a dual precision voltage comparator in SOIC-8 package, designed for single-supply operation from 2 V to 36 V. It delivers ±0.37 mV typical input offset voltage, 1 µs propagation delay, 200 µA per comparator supply current, and rail-to-rail input common-mode range including ground-enabling robust threshold detection in industrial power supplies and motor control feedback loops.

For engineers reviewing the LM393PSR datasheet, LM393PSR pinout, LM393PSR application, or LM393PSR equivalent, this page provides verified electrical specifications, validated pin functions, real-world use cases in server PSUs and cordless tools, and two confirmed alternative parts with documented functional and thermal differences.

Technical Context

The LM393PSR implements open-collector output architecture with independent dual comparators, supporting TTL/MOS/CMOS-compatible sinking outputs up to 25 mA. Its input stage features dedicated ESD clamps (2 kV HBM), enabling rugged operation in noisy industrial environments without external protection.

It operates across −40°C to +85°C ambient temperature, with input bias current as low as 3.5 nA (typ) and differential input voltage tolerance of ±38 V-allowing direct sensing of high-side signals referenced to VCC while maintaining accurate decision thresholds.

Key Specifications

Pinout & Package

LM393PSR is housed in an 8-pin SOIC package (4.90 mm × 3.91 mm body size) with standard JEDEC MS-012AC footprint and 1.27 mm pitch. Thermal performance is characterized by R_θJA = 148.5°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual comparator applications.

Compared with LM393DR and LM2903PSR, the LM393PSR provides identical performance at 85°C maximum ambient but with tighter logistics packaging - making it ideal for volume production of server PSUs and cordless tool chargers where thermal derating is not required.

Availability

LM393PSR is available at Aetrix Electronics and suitable for server power supplies, cordless power tools, and building automation systems requiring stable component supply, long-term lifecycle support, and traceable sourcing from authorized channels.

Supply support for LM393PSR 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 delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and consumer markets.

The LM393PSR belongs to TI's precision comparator product line, engineered for high-reliability industrial sensing and power management applications where accuracy, speed, and ruggedness are non-negotiable.

FAQ

What is the maximum supply voltage rating for LM393PSR?

The LM393PSR is rated for a maximum supply voltage of 36 V, exceeding the 30 V limit of legacy LM393 variants. This allows direct operation from unregulated 24 V industrial rails without pre-regulation, reducing bill-of-materials count and improving system efficiency. Absolute maximum ratings specify 38 V for short-duration transients, but continuous operation must remain ≤36 V per datasheet Section 5.1.

Does LM393PSR support rail-to-rail input operation?

Yes, the LM393PSR supports rail-to-rail input common-mode voltage range from ground to (VCC − 2 V). Either or both inputs may be driven up to VCC without damage or output malfunction, enabling direct interfacing with microcontroller GPIOs, op-amp outputs, or unbuffered reference voltages. This capability is explicitly confirmed in Section 5.5 and Figure 4-1 of the LM393B datasheet.

What is the typical propagation delay of LM393PSR at 5 V supply?

The LM393PSR exhibits a typical propagation delay of 1 µs at 5 V supply, measured under standard conditions (VO_PULLUP = 5 V, CL = 15 pF, RL = 5.1 kΩ, TA = 25°C). This value is consistent across the LM393B family and is specified in Section 5.7 of the datasheet. Delay remains stable across temperature (−40°C to +85°C) and supply (2–36 V), ensuring predictable timing in safety-critical fault-detection circuits.

Can LM393PSR replace older LM393 variants on existing PCBs?

Yes, LM393PSR is a drop-in replacement for LM393, LM293, and LM2903 in SOIC-8 packages. It shares identical pinout, footprint, and electrical behavior-including open-collector outputs, supply current, and input characteristics. The B-version enhancements (lower offset, higher voltage rating, improved ESD) do not require layout or schematic modifications, making it suitable for seamless design refreshes.

What output current can LM393PSR sink reliably?

The LM393PSR can reliably sink up to 25 mA per output channel at VCC = 36 V, as specified in Section 5.1 Absolute Maximum Ratings. Under recommended operating conditions (VCC ≤ 36 V, TA ≤ 85°C), sustained 20 mA sinking is supported without thermal derating. Output saturation voltage remains ≤400 mV at 4 mA sink, enabling clean TTL-level interfacing with minimal external components.