The LM358 operational amplifier is one of the most widely used general-purpose op amps in the electronics industry. Originally developed by National Semiconductor (now part of Texas Instruments), the LM358 op amp integrates two independent, high-gain, internally frequency-compensated amplifiers into a single 8-pin integrated circuit package. It operates on a single power supply from 3V to 30V (up to 32V for some manufacturers, or 36V for the LM358B) or dual supplies from ±1.5V to ±15V, with a common-mode input range that extends down to ground — a key advantage over older op amps like the μA741 that require dual-supply configurations.
The LM358 is equivalent to one half of the LM324 quad op amp and shares the same internal circuit topology. Its combination of low quiescent current (roughly one-fifth that of the MC1741), wide supply voltage range, and low cost has kept it a staple in sensor interfaces, active filters, transducer amplifiers, and DC gain blocks for over four decades.
LM358 Pinout
The LM358 comes in an 8-pin package with two independent op amp channels (A and B) sharing a common power supply.
Pin 1 — Output A: Output of the first op amp channel.
Pin 2 — Inverting Input A (IN−): Inverting input of channel A. The feedback network connects here in most amplifier configurations.
Pin 3 — Non-Inverting Input A (IN+): Non-inverting input of channel A. The signal input connects here in non-inverting amplifier and voltage follower circuits.
Pin 4 — GND (V−): Ground reference for single-supply operation, or the negative supply rail (V−) in dual-supply configurations.
Pin 5 — Non-Inverting Input B (IN+): Non-inverting input of channel B.
Pin 6 — Inverting Input B (IN−): Inverting input of channel B.
Pin 7 — Output B: Output of the second op amp channel.
Pin 8 — VCC (V+): Positive power supply. The maximum supply voltage depends on the specific variant and manufacturer — 30V for TI’s standard LM358, 32V for onsemi and ST versions, or up to 36V for TI’s LM358B.
Both op amp channels operate independently but share the same VCC and GND pins. Each channel can source up to 20 mA of output current, and the outputs are internally protected against short circuits.
How the LM358 Works
The LM358 contains two identical op amp circuits, each built as a two-stage internally compensated amplifier. The first stage is a differential input pair using PNP transistors, which is why the common-mode input range extends all the way down to ground (and even slightly below, to about −0.3V). This PNP input topology is also the reason the input range does not reach the positive supply rail — the upper limit of the common-mode input range is approximately VCC − 1.7V. The second stage provides additional voltage gain and drives the output.
Each op amp has an open-loop DC voltage gain of approximately 100 dB (100,000 V/V). In practice, external resistor networks set the closed-loop gain to a usable, stable value. The two fundamental configurations are:
Non-inverting amplifier: The input signal goes to the non-inverting input (IN+), and a resistor divider from the output to the inverting input (IN−) sets the gain. The closed-loop voltage gain is:
Av = 1 + (Rf / R1)
where Rf is the feedback resistor from output to IN−, and R1 connects IN− to ground.
Inverting amplifier: The input signal connects through an input resistor to the inverting input (IN−), while the non-inverting input (IN+) ties to a reference voltage (often ground). The gain is:
Av = −(Rf / R1)
where Rf is the feedback resistor and R1 is the input resistor. The negative sign indicates the output is 180° out of phase with the input.
A special case of the non-inverting configuration is the voltage follower (unity gain buffer), where the output connects directly back to the inverting input with no resistors. This gives a gain of exactly 1, providing impedance matching between a high-impedance source and a low-impedance load.
LM358 Circuit Diagrams and Applications
Non-Inverting Amplifier for Sensor Signal Conditioning
One of the most common LM358 applications is amplifying low-level sensor outputs. A temperature sensor outputting 10–200 mV can be amplified to a 0–5V range suitable for an ADC input. With Rf = 47 kΩ and R1 = 2 kΩ, the gain is approximately 24.5 V/V.
The non-inverting configuration is preferred for sensor work because it presents a very high input impedance (limited mainly by the op amp’s input bias current of approximately 20–45 nA typical, depending on manufacturer), which avoids loading the sensor output. For loads requiring more than 20 mA, the LM358 output can drive an external NPN or PNP transistor as a current buffer.
Voltage Comparator
Although the LM358 is designed as a linear amplifier, it works well as a basic voltage comparator for applications where response speed is not critical. A reference voltage on one input is compared against a varying signal on the other input. When the signal crosses the reference, the output swings from near ground to near VCC.
A common example is a dark-activated light using a photoresistor (LDR). The LDR and a fixed resistor R1 form a voltage divider connected to the inverting input (IN−), while a potentiometer sets the threshold voltage (Vref) on the non-inverting input (IN+).
When ambient light is strong, the LDR resistance is low, pulling the IN− voltage up above Vref — the output stays low and the LED is off. When light drops, the LDR resistance increases, the IN− voltage falls below Vref, and the output swings high to light the LED through a current-limiting resistor R2. Adjusting the potentiometer sets the light-level threshold at which the circuit triggers.
The LM358’s output does not swing rail-to-rail — it saturates at approximately VCC − 1.5V on the high side (with a light load on a 5V supply; the drop increases to VCC − 2V or more at higher supply voltages or heavier loads) and near 0V on the low side (typically 5–20 mV). For precision comparator applications requiring faster response, dedicated comparators like the LM393 (which shares the same pinout as the LM358) are a better choice.
Active Low-Pass Filter
The LM358 can implement a first-order or second-order active low-pass filter using standard Sallen-Key or multiple feedback topologies. A first-order active low-pass filter uses a single RC network — a resistor and capacitor — in the feedback path of a non-inverting amplifier configuration. The cutoff frequency is:
fc = 1 / (2π × R × C)
For example, with R = 10 kΩ and C = 100 nF, the cutoff frequency is approximately 159 Hz, which is suitable for filtering noise from DC sensor signals or audio processing below the voice band.
The LM358’s gain-bandwidth product of 0.7–1.1 MHz (depending on manufacturer) limits its usefulness for filters above a few hundred kHz. For audio-frequency filtering and below, it is perfectly adequate.
Voltage Follower (Unity Gain Buffer)
The voltage follower is the simplest LM358 circuit — the output connects directly to the inverting input, and the signal feeds into the non-inverting input. The output voltage equals the input voltage, but the circuit provides current gain: a high-impedance source driving a low-impedance load.
Typical use cases include buffering a voltage divider’s output before feeding it to an ADC, or isolating one circuit stage from another to prevent loading effects. The LM358 is unity-gain stable, meaning it does not oscillate in this configuration — not all op amps guarantee this.
How to Use the LM358
Single-Supply Operation
For single-supply operation, connect VCC (pin 8) to a positive supply between 3V and 30V (or up to 32V for onsemi/ST parts, 36V for TI’s LM358B), and connect GND (pin 4) to circuit ground. The input signal must stay within the common-mode range: from −0.3V to VCC − 1.7V. The output can swing from near ground (approximately 5–20 mV above GND at light loads) up to approximately VCC − 1.5V (at VCC = 5V with 2 kΩ load).
A common mistake is expecting the output to reach the full supply voltage. The LM358 is not a rail-to-rail output op amp. If your application needs the output to swing closer to VCC, consider the LM358B (which improves output swing somewhat) or switch to a true rail-to-rail op amp.
Dual-Supply Operation
For dual-supply operation, connect the positive supply to pin 8 and the negative supply to pin 4. The total voltage between V+ and V− must not exceed the device’s maximum rating — 30V for TI’s standard LM358, 32V for onsemi/ST versions, or 36V for TI’s LM358B. For example, ±15V (30V total) is within specification for all variants. In this configuration, the output swings symmetrically around ground, which is useful for AC signal processing.
Decoupling
Place a 0.1 µF ceramic bypass capacitor as close as possible to pin 8 (VCC) and pin 4 (GND). For circuits operating at very low frequencies or with long power supply leads, add a 10 µF electrolytic capacitor in parallel. Inadequate decoupling is the most common cause of oscillation and noise issues with the LM358.
Unused Channels
If only one of the two op amp channels is needed, do not leave the unused channel’s inputs floating. Connect the unused non-inverting input to ground and tie the unused inverting input to the unused output. This configures the unused channel as a voltage follower at ground potential, preventing it from oscillating and drawing excess current.
LM358 Features and Specifications
The following table summarizes the key electrical characteristics that matter for design decisions. Values are typical at 25°C unless noted otherwise.
| Parameter | LM358 (TI) | LM358A (TI) | LM358B (TI) |
|---|---|---|---|
| Supply voltage (single) | 3V to 30V | 3V to 30V | 3V to 36V |
| Supply voltage (dual) | ±1.5V to ±15V | ±1.5V to ±15V | ±1.5V to ±18V |
| Input offset voltage (max) | 7 mV | 3 mV | 3 mV |
| Input offset voltage (typical) | 2 mV | 2 mV | 0.3 mV |
| Input bias current (typical / max) | 20 nA / 250 nA | 15 nA / 100 nA | 10 nA / 35 nA |
| Gain bandwidth product | 0.7 MHz | 0.7 MHz | 1.2 MHz |
| Slew rate | 0.3 V/µs | 0.3 V/µs | 0.4 V/µs |
| Open-loop DC gain | 100 dB | 100 dB | 100 dB |
| Output source current (per channel) | 20 mA | 20 mA | 20 mA |
| Quiescent current (per channel) | 0.35 mA | 0.35 mA | 0.3 mA |
| Operating temperature | 0°C to 70°C | 0°C to 70°C | −40°C to 85°C |
| ESD protection (HBM) | 500 V | 500 V | 2 kV |
What the differences mean in practice:
The LM358A is a tighter-tolerance version of the standard LM358, with input offset voltage guaranteed to 3 mV maximum instead of 7 mV. Choose the LM358A when your circuit requires better DC accuracy — for example, precision current sensing or instrumentation where a few millivolts of offset directly affects measurement quality.
The LM358B is the next-generation replacement from Texas Instruments. It improves on nearly every specification: higher bandwidth (1.2 MHz vs 0.7 MHz), lower offset voltage (0.3 mV typical, 3 mV max), wider supply range (up to 36V), extended operating temperature (−40°C to 85°C), and built-in 2 kV ESD protection with EMI/RF filtering. The LM358B is pin-compatible with the original LM358, making it a drop-in upgrade for new designs. TI positions the LM358B as the preferred option, and its 1ku pricing is actually lower than the original LM358 in many package options.
Manufacturer Comparison
The LM358 is produced by multiple manufacturers. While the pinout and basic functionality are identical across vendors, there are differences that can affect sourcing decisions.
| Manufacturer | Part Number | Max Supply (Single) | GBW | Vos (max) | Temp Range | Key Packages |
|---|---|---|---|---|---|---|
| Texas Instruments | LM358 | 30V | 0.7 MHz | 7 mV | 0°C to 70°C | PDIP-8, SOIC-8, TSSOP-8 |
| Texas Instruments | LM358B | 36V | 1.2 MHz | 3 mV | −40°C to 85°C | PDIP-8, SOIC-8, TSSOP-8, VSSOP-8, SOT23-8 |
| onsemi | LM358 | 32V | 1.0 MHz | 7 mV | 0°C to 70°C | PDIP-8, SOIC-8, TSSOP-8, Micro-8 |
| STMicroelectronics | LM358 | 32V | 1.1 MHz | 7 mV | 0°C to 70°C | PDIP-8, SO-8, MiniSO-8, TSSOP-8 |
| Diodes Inc. | LM358 | 36V | 1.0 MHz | 7 mV | −40°C to 85°C | SOIC-8, MSOP-8 |
A few observations for sourcing:
TI’s original LM358 is rated at 30V maximum supply — slightly lower than onsemi and ST, which both rate their versions at 32V. If your design operates between 30V and 32V, check the specific vendor’s maximum rating. The LM358B from TI, however, goes up to 36V.
STMicroelectronics specifies 1.1 MHz GBW, while onsemi rates theirs at approximately 1.0 MHz, compared to TI’s 0.7 MHz for the standard LM358. These differences are small but can matter in filter designs where the gain-bandwidth product directly sets the usable frequency range.
For automotive or industrial applications requiring an extended temperature range, TI’s LM358B (−40°C to 85°C) or Diodes Inc.’s LM358 variant (also −40°C to 85°C) are the better choices among the LM358 family. For automotive qualification (AEC-Q100), onsemi’s NCV2904 is the standard option.
LM358 Applications
Beyond the circuit examples above, the LM358 finds use in a wide range of practical applications:
Transducer amplifiers — amplifying outputs from thermocouples, strain gauges, pressure sensors, and current-sense resistors where signal levels are in the millivolt range.
DC gain blocks — providing fixed-gain amplification stages in signal chains, particularly where low power consumption and single-supply operation are priorities.
Active filters — implementing low-pass, high-pass, and bandpass filters for frequencies up to a few hundred kHz, commonly used in audio processing, power supply monitoring, and data acquisition anti-aliasing.
Oscillators — the LM358 can serve as the active element in Wien bridge or phase-shift oscillators for low-frequency signal generation.
Voltage regulators — used as an error amplifier in discrete linear regulator circuits, comparing the output voltage against a reference and driving a pass transistor.
LED drivers — using one channel as a comparator or PWM controller to regulate LED current based on a reference voltage.
Battery monitoring — comparing battery voltage against a threshold using the comparator configuration to trigger low-battery indicators.
LM358 Equivalents
Choosing the right equivalent depends on whether you need a different channel count, wider temperature range, or improved specifications.
| Part Number | Channels | Max Supply (Single) | GBW | Temp Range | Relationship to LM358 |
|---|---|---|---|---|---|
| LM324 | 4 | 32V | 1.0 MHz | 0°C to 70°C | Quad version — two LM358s in one 14-pin package |
| LM2904 | 2 | 26V | 1.0 MHz | −40°C to +105°C | Industrial temp range version (lower max supply than LM358) |
| LM2904V / NCV2904 | 2 | 26V | 1.0 MHz | −40°C to +125°C | Automotive-grade version (AEC-Q100 for NCV2904) |
| LM321 | 1 | 32V | 1.0 MHz | 0°C to 70°C | Single-channel version in SOT23-5 package |
| LM158 | 2 | 32V | 0.7 MHz | −55°C to +125°C | Military temp range version |
| LM258 | 2 | 32V | 0.7 MHz | −25°C to +85°C | Extended commercial temp range |
| μA741 | 1 | ±18V (dual only) | 1.0 MHz | −55°C to +125°C | Classic op amp — requires dual supply, not pin-compatible |
LM324 is the most common LM358 equivalent. If your design uses both channels of the LM358 and needs additional amplifiers, migrating to a single LM324 saves board space and reduces component count. The LM324 uses a 14-pin DIP or SOIC package.
LM2904 is functionally identical to the LM358 but rated for the −40°C to +105°C temperature range (or −40°C to +125°C for the LM2904V variant). Note that the LM2904 has a lower maximum supply voltage (26V vs 30–32V), so it is not a direct drop-in replacement for circuits operating above 26V.
LM321 provides a single channel in a compact SOT23-5 package, ideal for space-constrained designs where only one amplifier is needed.
The μA741 is sometimes cited as an LM358 alternative, but the two are fundamentally different. The 741 requires a dual power supply (it cannot operate on a single supply), has a different pinout, and is available only as a single-channel device. The LM358 can replace the 741 in many circuits by adding a virtual ground reference, but the 741 cannot replace the LM358 in single-supply designs.
LM358 Package and Dimensions
The LM358 is available in multiple package types to suit different design requirements:
PDIP-8 (Plastic Dual In-Line Package): The classic through-hole package with 2.54 mm (0.1 inch) pin spacing. Ideal for prototyping, breadboard work, and through-hole PCB designs. Package dimensions are approximately 9.8 × 9.4 mm.
SOIC-8 (Small Outline Integrated Circuit): The standard surface-mount package with 1.27 mm pin pitch. This is the most popular package for production PCBs, balancing ease of soldering with reasonable board space savings. Package dimensions are approximately 4.9 × 6.0 mm.
TSSOP-8 (Thin Shrink Small Outline Package): A thinner, smaller surface-mount package with 0.65 mm pin pitch. Used where board space is a priority. Package dimensions are approximately 3.0 × 6.4 mm.
SOT23-8 / VSSOP-8: The smallest available packages, used in size-critical applications. The SOT23-8 has a 0.65 mm pitch in a package approximately 2.9 × 2.8 mm. The VSSOP-8 is approximately 3.0 × 4.9 mm. These packages are available primarily for the LM358B variant from TI.
For prototyping and evaluation, use the PDIP-8 package on a breadboard or perfboard. For production designs, the SOIC-8 is the default choice unless size constraints push you toward TSSOP-8 or SOT23-8. When selecting packages, verify that your specific vendor offers the LM358 in the desired package — not all manufacturers produce every package option.
LM358 Datasheet
The official datasheets from each major manufacturer provide complete electrical specifications, application notes, and recommended operating conditions:
- Texas Instruments LM358: LM358 Datasheet (Rev. AB) — covers the original LM358 in all TI package options.
- Texas Instruments LM358B: LM358B Datasheet — the next-generation version with improved specifications.
- onsemi LM358: LM358/D Datasheet (Rev. 36) — covers LM258, LM358, LM358A, LM2904, and NCV2904 variants.
- STMicroelectronics LM358: LM358 Datasheet (Rev. 15) — covers LM158, LM258, LM358, and A variants.
When comparing datasheets across manufacturers, pay close attention to the test conditions used for each specification. A parameter like “gain bandwidth product” might be measured at different supply voltages or load conditions, which can account for the differences between vendors noted in the manufacturer comparison table above.