on December 2th 14,688

Differences Between LM358 and LM393 Explained

The LM358 and LM393 are widely used integrated circuits that serve different purposes in electronics. The LM358 is a dual operational amplifier ideal for amplifying and processing signals, while the LM393 is a dual comparator designed for comparing voltages and driving external loads. This article explores their features, specifications, and applications to help you understand their roles and choose the right one for your needs.

Catalog

Introduction to LM358 and LM393 ICs

Overview of LM358 IC

The LM358 is a versatile integrated circuit with two operational amplifiers (op-amps) that can run on a single power source. It is essentially a scaled-down version of the LM324 Quad op-amp, which includes four similar amplifiers. What makes the LM358 stand out is its ability to operate across a wide range of input voltages, matching its power supply range.

One notable feature of this IC is its very low default input offset voltage, which is only 2mV. This means it offers precise performance right out of the box. The power consumption is also efficient, with a typical current of 500uA and a maximum of 700uA, regardless of the supply voltage.

Temperature tolerance is another strength of the LM358. It functions reliably in ambient temperatures between 0˚C and 70˚C, with a maximum junction temperature rating of 150˚C, making it suitable for various environments. Overall, the LM358 delivers reliable and consistent performance in a compact package.

Overview of LM393 IC

The LM393 is an integrated circuit specifically designed for use as a voltage comparator, distinguishing it from the LM358 operational amplifier. While many op-amps can function as comparators, the LM393 stands out because of its open collector output. This feature makes it especially effective for driving loads, as it allows more flexibility in connecting external components.

One of the key capabilities of the LM393 is its ability to handle loads up to 50V and 50mA. This makes it a practical choice for working with typical TTL, MOS, and RTL logic levels. Additionally, its output transistor can keep the load isolated from the system ground, which adds versatility and safety to its applications. If you’re looking for a comparator to handle such tasks, the LM393 is a reliable and efficient option to consider.

Detailed Specifications of LM358 and LM393 ICs

Parameter	Specification
Operating Voltage Range (Single Supply)	2.0 Vdc to 36 Vdc
Split Supply Range	±1.0 Vdc to ±18 Vdc
Current Consumption (Independent of Supply)	0.4 mA
Input Bias Current	25 nA
Input Offset Current	5.0 nA
Input Offset Voltage	5.0 mV (maximum)
Input Common Mode Range	Extends to Ground Level
Differential Input Voltage Range	Equals the Power Supply Voltage
Output Voltage Compatibility	DTL, ECL, TTL, MOS, and CMOS Logic Levels
ESD Clamps	Present on Inputs for Enhanced Durability
Automotive Applications	Prefix "NCV", Compliant with AEC−Q100 and PPAP Standards
Environmental Compliance	Pb-Free, Halogen-Free, BFR-Free, RoHS Compliant

Pinout Details of LM358 and LM393 ICs

LM358 Pin Configuration

LM393 Pin Configuration

Pin Functions of LM358 and LM393

Pin No.	Pin Name	Description
1	OUTPUT1	The output of Op-Amp 1
2	INPUT1-	Inverting Input of Op-Amp 1
3	INPUT1+	Non-Inverting Input of Op-Amp 1
4	VEE, GND	Ground or Negative Supply Voltage
5	INPUT2+	Non-Inverting Input of Op-Amp 2
6	INPUT2-	Inverting Input of Op-Amp 2
7	OUTPUT2	The output of Op-Amp 2
8	VCC	Positive Supply Voltage

Comparing Key Features of LM358 and LM393

Specification	LM358	LM393
Supply Voltage	32V, +/-16V	36V, +/-18V
Differential Input Voltage	32V	36V
Input Offset Voltage	3mV max.	5mV max.
Input Bias Current	100nA max.	250nA max.
Input Common Mode Range	0V to V+ - 2V	0V to V+ - 1.5V
Large Signal Voltage Gain	100V/mV typ.	200V/mV typ.
Bandwidth	1MHz	Not specified

Internal Architecture Comparison of LM358 and LM393

When you first look at the internal designs of the LM358 and LM393, they might seem similar. However, a closer analysis shows key differences that align with their unique uses and specifications.

Both ICs use input stages that resemble "Darlington-connected" PNP transistors, allowing them to sense signals close to the ground. However, the current levels in their differential stages differ. The LM393 operates at a higher current, which helps it amplify and switch outputs quickly—an essential characteristic for its role as a comparator. On the other hand, the LM358, designed as a linear amplifier, doesn’t require such high currents, so this difference is less significant for its operation.

The most noticeable distinction is in their output stages. The LM393 has a simpler output design optimized for rapid switching between voltage levels, which suits its function as a comparator. Its open-collector output also provides more flexibility for connecting external components. In contrast, the LM358 has a fully linear output stage, delivering a smooth and continuous relationship between input and output—ideal for amplification tasks. These structural differences underline the specific strengths of each IC in their respective applications.

Applications of LM358 and LM393

LM358 Applications

• Transducer Amplifiers

The LM358 is well-suited for transducer amplifiers, where it processes signals from devices like sensors and converts them into a usable format. Its dual operational amplifiers allow it to handle these tasks efficiently in many environments.

• Conventional Op-Amp Circuits

This IC is commonly used in basic operational amplifier circuits, such as amplifying, buffering, or processing signals. Its reliable performance and flexibility make it a popular choice for general-purpose applications.

• Integrators, Differentiators, Summers, Adders, and Voltage Followers

The LM358 supports various mathematical and signal-processing functions, including integration, differentiation, and addition of signals. It can also act as a voltage follower, stabilizing voltage levels in circuits.

• DC Gain Blocks, Digital Multimeters, and Oscilloscopes

Its ability to provide stable DC gain makes it valuable in devices like multimeters and oscilloscopes, where accuracy and reliability are needed for measuring and analyzing signals.

• Comparators for Loop Control and Regulation

The LM358 can also function as a comparator in feedback control systems. It helps maintain steady operation in applications requiring precise regulation of current or voltage.

LM393 Applications

• Voltage Comparator Circuits

The LM393 is designed specifically for voltage comparison. It compares two input voltages and delivers a clear output signal, making it ideal for precision tasks.

• Driving Relays, Lamps, and Motors

With its open collector output, the LM393 can control external devices like relays, lamps, and motors, providing efficient load-driving capabilities in various applications.

• Zero Crossing Detectors

This IC is commonly used in circuits that need to detect the point where an AC signal crosses the zero voltage level, ensuring proper timing for signal synchronization.

• Peak Voltage Detectors

The LM393 can help detect the highest voltage in a signal, making it useful in applications like signal analysis or protection circuits.

• High Voltage Protection and Warning Systems

Its ability to handle high voltages allows the LM393 to play a role in protection systems, where it monitors and reacts to unsafe voltage levels.

• Oscillator Circuits

The LM393 is often found in oscillator circuits, which generate consistent signals for timing or waveform applications, enhancing its versatility in electronic systems.

Equivalents of LM358 and LM393

LM358 Equivalents

• LM358A

• LM358E

• LM358-N

• LM358W

LM393 Equivalents

• LM358

• TL082

• LM311

Key Differences Between LM358 and LM393

LM358	LM393
Dual operational amplifier	Dual comparator
Relatively better input specifications	Relatively worse input specifications
Output linear with input	Non-linear output
Stable with negative feedback	Stable with positive feedback

Conclusion

The LM358 and LM393 are versatile and reliable ICs designed for different applications. The LM358 is ideal for amplifying and processing signals, while the LM393 excels at comparing voltages and driving loads. Understanding their features and differences helps you choose the right one for your needs. Both ICs offer practical solutions for a wide range of tasks in electronics.