Texas Instruments LP324M

Overview

LP324M from Texas Instruments is a micropower quad operational amplifier optimized for battery-powered and single-supply systems, featuring 85 μA typical supply current, 2 mV typical input offset voltage, and rail-to-ground input common-mode range. It operates from 3 V to 32 V and interfaces directly with CMOS logic in portable instrumentation and backup power circuits.

For engineers reviewing the LP324M datasheet, LP324M pinout, LP324M application, or LP324M equivalent, key selection criteria include micropower operation (<100 μA), ground-sensing inputs, output swing within 1.9 V of V+, and SOIC-14 packaging for space-constrained analog signal conditioning.

Technical Context

The LP324M integrates four independent, internally compensated op-amps with class-B output stages enabling both sourcing and sinking capability. Its input stage supports common-mode voltages down to ground, eliminating need for input biasing in single-supply configurations.

It delivers 100 kHz gain-bandwidth product and 50 V/ms slew rate-optimized for DC-precision and low-frequency signal conditioning rather than high-speed AC performance. The device is rated for 0°C to +70°C ambient operation and features ±500 V HBM ESD protection.

Key Specifications

Pinout & Package

LP324M is housed in a 14-pin SOIC (D package), 3.9 mm × 8.65 mm body, 1.75 mm max height, with standard JEDEC MS-012AB footprint. Pin 1 marked by notch or beveled corner; pins spaced at 1.27 mm pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad operational amplifier applications.

Compared with LM324DR, LP324M reduces supply current by 94% and enables true ground-referenced sensing; compared with LP324MT/NOPB, it offers identical analog performance in a more robust, hand-solderable SOIC package with higher thermal resistance but easier prototyping and repair.

Availability

LP324M is available at Aetrix Electronics and suitable for portable instrumentation, battery backup equipment, and single-supply sensor interfaces requiring stable component supply across industrial and consumer production cycles.

Supply support for LP324M 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 90 years of innovation in precision analog design.

The LP324M belongs to TI's micropower operational amplifier product line, engineered specifically for ultra-low-quiescent-current signal conditioning in energy-constrained systems such as wearables, remote sensors, and battery-backed monitoring devices.

FAQ

What is the maximum operating temperature range for the LP324M?

The LP324M is specified for operation from 0°C to +70°C ambient temperature. This commercial-grade rating reflects its target use in consumer and industrial portable equipment-not extended-temperature automotive or military applications. Derating is required above 70°C; junction temperature must remain below 150°C under all conditions. Always verify thermal design margins using θJA = 140°C/W for the SOIC (D) package when calculating power dissipation.

Is the LP324M pin-compatible with the LM324?

Yes, the LP324M is explicitly designed as a pin-for-pin replacement for the LM324 in SOIC-14 packaging. All 14 pins retain identical functions-including V+, V−, four sets of inverting/non-inverting inputs and outputs-enabling direct substitution without PCB modification. However, note that LP324M's lower supply current and improved input specifications may require minor recalibration of feedback networks in legacy designs originally tuned for LM324's higher offset and bias errors.

Can the LP324M drive capacitive loads without oscillation?

Yes, the LP324M is internally compensated for stable operation with capacitive loads ranging from 50 pF to 1000 pF-covering typical ADC input capacitance, long PCB traces, and ceramic bypass caps. No external isolation resistor is needed in standard configurations. For loads exceeding 1000 pF or in high-noise environments, adding a 10–100 Ω series resistor between output and load improves phase margin without degrading DC accuracy.

Does the LP324M support single-supply operation with input signals at ground potential?

Yes, the LP324M features an input common-mode voltage range that includes ground (0 V), allowing direct connection of sensors, switches, or reference points referenced to system GND. This eliminates the need for level-shifting networks or dual supplies in applications like battery voltage monitoring or thermistor interfacing. Ensure input voltages do not fall below −0.3 V relative to GND to avoid parasitic conduction.

What is the typical output short-circuit current for the LP324M?

The LP324M can source up to 35 mA and sink up to 45 mA into short-circuit conditions (per amplifier), but continuous short-circuit operation is not recommended. At V+ = 10 V, simultaneous shorting of all four outputs to GND raises junction temperature by ~110°C-exceeding safe limits. Use current-limiting resistors or external protection circuits in fault-prone applications. Absolute maximum ratings specify ±500 V HBM ESD tolerance, not short-circuit survivability.