The LM358 is a dual general-purpose operational amplifier built for single-supply operation. It is one of the most widely used analog ICs in production for one reason: its inputs sense all the way down to the negative rail, so the whole circuit can run from a single positive supply and ground, with no split rail and no virtual-ground reference.
Combined with a 3 V to 32 V supply range and a cost of a few cents in volume, that property puts the LM358 in sensor front-ends, battery monitors, motor controllers, and instrumentation across nearly every product category. It also has one well-documented limitation—an output stage that distorts near ground—that this guide explains so you can design around it rather than discover it on a scope.
Table of Contents
What is the LM358?
The LM358 packages two independent op amps into one 8-pin device. Each amplifier shares the supply pins but is otherwise fully separate, so the two channels can run unrelated circuits.
The same internal design appears in related parts: the LM324 is the quad version (four amplifiers), and the LM2904 is the automotive-grade equivalent. National Semiconductor introduced the architecture in the late 1970s, and Texas Instruments now maintains the canonical part. The TI LM358 datasheet and the ON Semiconductor LM358 datasheet are the authoritative references for electrical limits.
The design goals were low supply current and single-supply operation—not speed or low distortion. Every characteristic of the part follows from those two goals.
LM358 pinout
The LM358 uses a standard 8-pin layout, available as PDIP, SOIC, TSSOP, VSSOP, and SOT-23-8. Pin numbering is identical across all of them, so a design drawn around the DIP pinout transfers directly to a surface-mount layout.
| Pin | Name | Function |
|---|---|---|
| 1 | OUT1 | Output, amplifier A |
| 2 | IN1− | Inverting input, amplifier A |
| 3 | IN1+ | Non-inverting input, amplifier A |
| 4 | V− / GND | Negative supply (ground in single-supply use) |
| 5 | IN2+ | Non-inverting input, amplifier B |
| 6 | IN2− | Inverting input, amplifier B |
| 7 | OUT2 | Output, amplifier B |
| 8 | V+ / VCC | Positive supply |
The two amplifiers mirror across the package. Channel A occupies pins 1–3, channel B occupies pins 5–7, and the supply pins sit at opposite corners—pin 4 negative, pin 8 positive. In single-supply use there is no separate ground pin: pin 4 is the negative rail, tied to system ground.
One practical rule for board bring-up: if only one amplifier is used, do not leave the other floating. Wire it as a unity-gain follower with its non-inverting input tied to a fixed voltage (mid-rail or ground) so its output stays in a defined state and does not oscillate or couple noise through the shared supply.
LM358 features and parameters
The values below describe the classic LM358—what most generic parts and breakout boards actually contain. TI’s newer B and BA grades improve several of these, noted in the table.
| Parameter | Classic LM358 | Notes |
|---|---|---|
| Supply voltage (single) | 3 V to 32 V | 3 V to 36 V on B/BA grades |
| Supply voltage (dual) | ±1.5 V to ±16 V | |
| Supply current (total) | 0.7 mA typ (at 5 V) | 300 µA per channel on B grade |
| Large-signal voltage gain | 100 dB typ | |
| Gain-bandwidth product | ~0.7–1.1 MHz | varies by manufacturer (TI 0.7 MHz, ST 1.1 MHz); 1.2 MHz on B grade |
| Slew rate | 0.3 V/µs | |
| Input offset voltage | 2 mV typ, 7 mV max | 3 mV max (A/B), 2 mV max (BA) |
| Input bias current | −20 nA typ | flows out of inputs (PNP input stage) |
| Input common-mode range | V− (0 V) to V+ − 1.5 V | includes ground |
| Output voltage swing | V− to V+ − 1.5 V | reaches ground; not the positive rail |
| Output source current | 40 mA typ (20 mA min) | at V+ = 15 V |
| Output sink current | 20 mA typ (10 mA min) | at V+ = 15 V |
| Output short-circuit current | ~40 mA (60 mA max) | internally limited |
| CMRR | ~80 dB typ | |
| Operating temperature | 0 °C to 70 °C | LM358 grade |
Three numbers drive most design decisions. The 0.3 V/µs slew rate and ~1 MHz gain-bandwidth product place the LM358 in the slow, general-purpose class—right for DC and low-frequency signals, wrong for fast or high-fidelity audio. The common-mode range that includes ground is the reason the part exists, because it lets the amplifier read signals referenced to the negative rail directly. The output swing limit—output reaches ground but stops about 1.5 V below V+—is the constraint most often missed: the LM358 is not a rail-to-rail part, even though it is frequently used as if it were.
Bandwidth and slew-rate limits
Two numbers bound what the LM358 can do with a changing signal, and they bind at different points. The gain-bandwidth product (~1 MHz) sets the small-signal limit: closed-loop bandwidth is roughly GBW / Av, so a gain of 10 leaves about 100 kHz and a gain of 100 about 10 kHz. The slew rate (0.3 V/µs) sets the large-signal limit independently—the largest undistorted sine of peak amplitude Vp is f_max = SR / (2π · Vp). A 2 V peak output is therefore slew-limited to about 24 kHz regardless of gain. Whichever limit is lower governs, so large output swings hit the slew wall well before the gain-bandwidth wall.
Absolute maximum ratings
These are stress limits, not operating targets. Exceeding them risks permanent damage.
| Rating | Limit |
|---|---|
| Supply voltage | 32 V (single) / ±16 V (dual) |
| Differential input voltage | up to the supply voltage |
| Input voltage | must not go below V− by more than 0.3 V |
| Output short to ground | continuous (internally limited) |
| Storage temperature | −65 °C to +150 °C |
LM358 applications
Every LM358 circuit sets its gain and function with external resistors and capacitors around the same two amplifiers, and across those circuits the part fills a consistent set of roles. It amplifies small sensor and transducer signals (non-inverting, inverting, and differential stages); buffers a high-impedance source into an ADC or load (the follower); detects thresholds for light, battery, and level flags (comparator and Schmitt trigger); filters in anti-aliasing and control loops (active low-pass and band-pass); performs signal-conditioning math such as summing and integration; interfaces sensors directly on one rail (LDR light or dark, piezo shock, low-side current shunt); buffers references and boosts current to drive relays, LEDs, and small motors; and generates waveforms with no external clock (Wien-bridge sine and square wave). The single-supply, ground-sensing input is what lets most of these run from one rail, which is why the LM358 turns up in battery, automotive, and industrial designs and not in fast or low-noise signal paths.
The three basic gain stages come first—non-inverting, inverting, and follower—followed by the application circuits built on them, several of which the datasheet lists as typical uses.
LM358 non-inverting amplifier
The signal drives IN+, and two resistors from the output through IN− to ground set the gain:
Av = 1 + (Rf / Rg)
where Rf is the feedback resistor and Rg the resistor from IN− to ground. Because IN+ is high impedance, this configuration loads the source lightly—the default for amplifying a sensor or reference.
Worked example: a sensor outputs 100 mV and the ADC needs 1.1 V, a gain of 11. Set Rf = 10 kΩ and Rg = 1 kΩ:
Av = 1 + (10 kΩ / 1 kΩ) = 11, so Vout = 11 × 0.1 V = 1.1 V.
For DC signals referenced to ground, no input biasing is needed—the common-mode-to-ground capability handles it.
LM358 inverting amplifier
The signal drives IN− through a resistor, with IN+ held at a reference (ground in dual-supply use, mid-rail in single supply):
Av = − (Rf / Rin)
Worked example: for a gain of −10 with Rin = 1 kΩ, set Rf = 10 kΩ. The output inverts and scales the input by 10. Because the output inverts, a true bipolar result (−10 V for a +1 V input) requires a dual supply; on a single supply, IN+ is biased to mid-rail and the gain applies to the AC signal swinging around that point. The tradeoff against the non-inverting form is input impedance: the source sees Rin directly, a heavier load.
LM358 voltage follower
Tying the output straight to IN− gives unity gain and the highest input impedance the part offers:
Vout = Vin
The follower isolates a high-impedance source—a resistive divider, a sensor, a reference—from a load that would otherwise pull it down. It rarely drives the output near the rails, so it is one of the LM358’s cleanest uses.
Built on those three gain stages, a consistent set of application circuits recurs across LM358 designs:
LM358 active low-pass filter
A single-pole or Sallen-Key stage suits anti-aliasing and control-loop filtering. The cutoff of a single RC pole is fc = 1 / (2π R C). Keep the corner well below the ~1 MHz gain-bandwidth product; in practice that confines useful filters to the low tens of kilohertz and below, which covers most sensor and control work.
LM358 comparator and Schmitt trigger
The LM358 works as a comparator, but it is an op amp without the open-collector output or speed of a dedicated comparator such as the LM393. For slow threshold detection—a low-battery flag, a light switch—it is fine. Adding a positive-feedback resistor turns it into a Schmitt trigger with hysteresis, which prevents output chatter when the input crosses the threshold slowly.
LM358 summing amplifier
Several inputs through individual resistors into IN− sum at the virtual ground of an inverting stage, producing a weighted sum. This is the basis for simple analog mixing, offset addition, and resistor-ladder DACs.
LM358 integrator (and the differentiator caveat)
A capacitor in the feedback path turns the inverting stage into an integrator, useful for slow ramp generation and control loops. The mirror circuit—a differentiator, with the capacitor on the input—is a poor fit for the LM358: its low gain-bandwidth and the way a differentiator amplifies high-frequency noise make the output noisy and prone to instability. For edge or rate detection, choose a faster, quieter op amp.
LM358 differential amplifier
With matched resistor pairs on both inputs, the LM358 amplifies the difference between two signals and rejects what is common to both. The datasheet shows a high-input-impedance differential configuration as a standard use.
LM358 light or dark sensor
A photoresistor (LDR) in a divider feeds one input while a reference divider sets the threshold on the other; the output switches a transistor and LED as light crosses the set point. A trimmer on the reference sets sensitivity. This is one of the most common beginner LM358 projects and works directly on a single supply.
LM358 shock or vibration alarm
A piezoelectric sensor drives one input and a reference sets the threshold on the other, with the LM358 wired as a Schmitt trigger. A tap or vibration trips the output and sounds a buzzer—the basis of simple anti-theft alarms for doors and vehicles.
LM358 Wien-bridge oscillator
With a Wien-bridge network in the feedback path, the LM358 generates a clean sine wave whose frequency is f = 1 / (2π R C). The datasheet lists this oscillator as a typical application; it is favored for good waveform shape and frequency stability at audio frequencies.
LM358 square-wave generator
One amplifier wired as a relaxation oscillator produces a square wave with no external clock. A resistor and capacitor on IN− set the timing while a positive-feedback divider on IN+ sets the switching thresholds; the capacitor charges and discharges between them and the output toggles between the rails. The frequency is f = 1 / (2 R C · ln((1 + β) / (1 − β))), where β is the feedback-divider ratio; with equal divider resistors this simplifies to about f ≈ 1 / (2.2 R C). The slow output stage keeps the usable frequency to the low tens of kilohertz.
LM358 voltage reference buffer
Following a reference such as a TL431 with an LM358 follower or non-inverting stage produces a buffered, scalable reference, with the output set by Vout = Vref × (1 + R1 / R2). The buffer isolates the reference from load current that would otherwise shift it.
LM358 low-side current sensing
The common-mode-to-ground capability lets the LM358 read the small voltage across a shunt placed between the load return and ground, with no level shifting. High-side sensing—shunt in the positive rail—puts the common-mode voltage near V+, outside the LM358’s input range, and calls for a dedicated current-sense amplifier instead.
LM358 current boost with external transistors
Where a load needs more than the LM358’s 40 mA source or 20 mA sink—a relay, a small motor, an LED string—external NPN and PNP transistors inside the feedback loop extend the drive while the amplifier keeps the accuracy. The datasheet documents this directly, since the output stage was designed to allow it.
How the LM358 works
The LM358 is built as two identical two-stage amplifiers, each internally frequency-compensated so it stays stable at unity gain with no external parts. Two design choices define how it behaves.
Basic operation
Each amplifier follows the standard op-amp rule. With negative feedback it drives its output until the two inputs sit at the same voltage; open-loop it acts as a comparator—when IN+ is above IN−, the output swings toward the positive rail (stopping about 1.5 V below it), and when IN+ is below IN−, the output falls toward the negative rail, reaching ground on a single supply. The two channels are independent: channel A compares pins 3 and 2 with its output on pin 1, channel B compares pins 5 and 6 with its output on pin 7. Because the output already pulls down to ground, the amplifier reads a valid low with no pull-up resistor—unlike an open-collector comparator such as the LM393, which needs one.
Input stage and ground sensing
The input stage uses a PNP differential pair. That is what lets the inputs work right down to the negative rail—the common-mode range includes ground—so a single-supply circuit can read sensors and dividers referenced to ground with no level shifting. It is the single feature that made the LM358 ubiquitous.
Output stage and crossover distortion
To hold quiescent current low, the output runs class-A for small signals and switches to class-B for large ones, and the two output transistors are not pre-biased the way a conventional complementary stage would be. TI’s application engineers describe the consequence on the TI E2E support forum: the output must rise about one diode drop above ground to bias the transistor that sinks output current.
The result is crossover distortion. As the output swings through the region near the negative rail, there is a brief interval where neither output transistor conducts and no current reaches the load. On a sine wave this shows up as a notch at the zero crossing, and it worsens with frequency because the slow output stage has less time to recover. Rod Elliott’s ESP analysis of the LM358 for audio traces it through the internal schematic and shows the distortion is built into the topology, not a defect.
The fix is a pull-down resistor from the output to ground. It forces a small standing current through the output stage, holds it in class-A across the full swing, and removes the notch. The tradeoff is current draw. For DC and slow signals that never approach ground, the behavior is irrelevant—which is why the LM358 works cleanly in most of its applications.
Built-in protection
The inputs carry ESD clamp structures and the output is internally current-limited, so a short from output to ground is survivable rather than immediately destructive. That ruggedness is part of why the LM358 is favored in noisy industrial and automotive environments.
LM358 advantages and limitations
The LM358’s strengths and weaknesses both trace to one design choice: a PNP input stage and a low-quiescent-current output stage, tuned for single-supply operation and cost rather than speed or fidelity.
Advantages. The input common-mode range includes the negative rail, so the part reads ground-referenced sensors and dividers directly on a single supply—no split rail, no virtual ground. The supply range is wide (3 V to 32 V, 36 V on B grades) and the total quiescent current is low (about 0.7 mA), which suits battery and always-on designs. Two independent amplifiers share one 8-pin package. The inputs are ESD-protected and the output is internally short-circuit limited, so the part tolerates the rough handling of industrial and automotive boards. It is internally compensated for unity-gain stability, needing no external compensation parts, and at a few cents in volume it is among the cheapest op amps available.
Limitations. The output is not rail-to-rail: it reaches the negative rail but stops about 1.5 V below V+, so it cannot drive a load or logic input that expects a near-full-supply high. It is slow—roughly 1 MHz gain-bandwidth and 0.3 V/µs slew—which rules out fast or high-fidelity signals. Its output stage produces crossover distortion near ground unless a pull-down resistor holds it in class-A, making it a poor default for audio. And its input noise is unremarkable, so low-noise front-ends need a different part. None of these are defects; they are the cost of a part built for cheap single-supply DC and low-frequency work, where it is hard to beat.
Single-supply design tips
Most LM358 mistakes trace back to single-supply biasing, not the part. Four rules cover almost all of them.
Bias to mid-rail for AC signals. The output cannot swing below ground, so an AC signal centered on ground would clip on its negative half. A divider from V+ to ground sets a mid-rail reference, decoupled with a capacitor to keep it quiet.
The output never reaches V+. It stops about 1.5 V below the positive rail. A design that needs the output near V+—driving a logic input that expects a near-full-supply high, say—needs a rail-to-rail part instead.
Keep inputs inside the common-mode range. Valid inputs run from ground up to V+ − 1.5 V. An input above that range, or below V− by more than 0.3 V, pushes the amplifier out of its linear region; series input resistors limit fault current when a source can drive beyond the rails.
Decouple the supply. A 0.1 µF capacitor close to pin 8 prevents supply-coupled instability, especially when both channels switch loads.
LM358 equivalents and alternatives
The LM358 is rarely the only candidate for a socket. The table covers the parts most often weighed against it.
| Part | Type | Difference vs LM358 | Choose when |
|---|---|---|---|
| LM324 | Quad bipolar | Four amplifiers, identical circuit | More than two channels are needed |
| LM2904 | Dual bipolar | Automotive temperature grade (−40 to +125 °C); the -Q1 variant is AEC-Q100 qualified | Automotive or high-reliability use |
| LMV358 | Dual CMOS | Rail-to-rail output, 2.7–5.5 V, ~1 MHz | Low-voltage rails needing full output swing |
| TL072 | Dual JFET | ~3 MHz, 13 V/µs, low noise; dual supply | Audio and higher-frequency paths |
| NE5532 | Dual bipolar | ~10 MHz, low noise; dual-supply audio | Low-noise audio preamps and filters |
| MCP6002 | Dual CMOS | Rail-to-rail in/out, 1.8–6 V, ~100 µA | Battery designs needing full swing |
The pattern is consistent: the LM358 wins on supply range, ground-sensing, and cost; it loses on output swing, speed, and noise. For a low single rail that needs full output swing, a CMOS rail-to-rail part such as the LMV358 or MCP6002 is the direct upgrade. For audio or any low-distortion path, the TL072 or NE5532 is correct and the LM358 should not be forced into the role.
That last point has a sourcing consequence. The LM358’s reputation as a cheap part has made it a common counterfeit substitute—low-cost listings for premium op amps like the TL072 frequently ship relabeled LM358 dies, a swap that stays invisible until the distortion shows up on a scope. Verifying the part against an authorized source is the only reliable defense.
LM358 vs LM324 and LM741
The two parts the LM358 is most often compared against sit on either side of it. The LM324 is the same circuit in a quad: four amplifiers in a 14-pin package instead of two in an 8-pin, with identical electrical behavior and a larger total power-dissipation budget. The choice between them is purely channel count—two channels take the LM358, three or four take the LM324, and a board can often be redrawn from one to the other with no other changes.
The LM741 is the older single-amplifier classic, and the contrast is sharper. The 741 needs a dual supply: its inputs do not reach the negative rail, so it cannot read ground-referenced signals on a single supply—exactly what the LM358 was built to do. The 741 also draws higher input bias current and comes one amplifier to a package. For any single-supply or battery design the LM358 is the modern replacement; the 741 survives mainly in legacy circuits and teaching examples.
LM358 packages, part numbers, and sourcing
“LM358” is a family, and the suffix determines what arrives.
The base grades carry the original specifications, with the A grade holding tighter offset. TI’s B and BA grades (LM358B, LM358BA) tighten offset further, raise gain-bandwidth to 1.2 MHz, add integrated EMI and RF filtering, and extend the supply range to 36 V. The TI LM358 product page positions the B grade as a pin-compatible upgrade, so a board laid out for the classic part can take the improved version unchanged.
Temperature grade tracks the prefix, not the suffix. LM358 is rated 0 °C to 70 °C, LM258 covers −25 °C to 85 °C, and LM158 covers the full −55 °C to 125 °C military range—the same die screened to different limits.
The package appears in the final letters: LM358P for PDIP, LM358N for the through-hole DIP from some makers, LM358D or LM358DR for SOIC (R = tape-and-reel), and LM358PW or LM358DGK for the smaller TSSOP and VSSOP outlines. The B grade adds the smaller SOT-23-8 outline; ceramic and metal-can packages exist for the LM158/LM258 high-reliability grades rather than the commercial LM358. The marking on the chip carries the part number and a date or batch code, which is the first thing to check when verifying a part against its datasheet.
Selecting and sourcing
The selection sequence is short. Confirm the signal is DC or low-frequency and does not need the output to reach the positive rail—if it does, move to a rail-to-rail CMOS part. Confirm the path is not audio or low-noise—if it is, move to a JFET or low-noise bipolar part. Once the LM358 is the right architecture, the remaining choices are grade (classic, A, or B for offset and bandwidth), temperature range (LM358, LM258, or LM158), and package.
For a design that runs near ground in an AC path, no grade removes the crossover behavior—that is inherent to the architecture and needs the output pull-down resistor regardless of suffix. The grade decision is about offset, bandwidth, supply range, and qualification level, not the output stage.
When sourcing, confirm the full part number and package against the manufacturer datasheet, verify the grade matches the design’s temperature and supply needs, and buy from authorized distribution to avoid the relabeled-die problem that affects the cheapest channels. The cost difference between a verified part and a counterfeit is measured in cents; the cost of finding the substitution in a production run is not.