LM324 - Quad Op-Amp, 3V-32V Single Supply | TI
MPN: LM324 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.65 | $0.65 |
| 10 | $0.58 | $5.80 |
| 100 | $0.42 | $42.00 |
| 500 | $0.35 | $175.00 |
| 1,000 | $0.29 | $290.00 |
Drop-in alternatives for LM324 β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
LM324A
β Drop-Inπ Reference alternative (not in catalog)
LM324B
β Drop-Inπ Reference alternative (not in catalog)
LM2902
β Drop-Inπ Reference alternative (not in catalog)
LMC660
β Drop-Inπ Reference alternative (not in catalog)
LM324N
β Drop-Inπ Reference alternative (not in catalog)
LM324DT
β Drop-Inβ In Stock
$0.0827 / Unit
View Datasheet βLM324 Maximum Ratings & Electrical Characteristics
| Amplifier Channels | 4 |
| Supply Voltage (Single) | 3 V to 32 V |
| Supply Voltage (Dual) | +/-1.5 V to +/-16 V |
| Slew Rate | [DATA_NEEDED: slew rate] |
| Gain-Bandwidth Product | [DATA_NEEDED: GBW] |
| Common-Mode Input Range | Includes ground (negative rail) |
| Output Swing | Near ground without external components |
| Quiescent Current (per amplifier) | Approx. one-fifth of MC1741 |
| Package | 14-pin PDIP (LM324N) |
| Mounting Type | Through Hole |
| Frequency Compensation | Internal |
| Inputs | True differential |
| Operating Temperature (LM324) | [DATA_NEEDED: temperature range] |
| RoHS Status | Compliant |
| Manufacturer Options | TI, onsemi, STMicroelectronics |
LM324 Pin Configuration
| Pin 1 | OUT1 β Amplifier 1 output |
| Pin 2 | IN1- β Amplifier 1 inverting input |
| Pin 3 | IN1+ β Amplifier 1 non-inverting input |
| Pin 4 | V+ β Positive supply (up to 32V single) |
| Pin 5 | IN2+ β Amplifier 2 non-inverting input |
| Pin 6 | IN2- β Amplifier 2 inverting input |
| Pin 7 | OUT2 β Amplifier 2 output |
| Pin 8 | OUT3 β Amplifier 3 output |
| Pin 9 | IN3- β Amplifier 3 inverting input |
| Pin 10 | IN3+ β Amplifier 3 non-inverting input |
| Pin 11 | GND/VEE β Ground or negative supply |
| Pin 12 | IN4+ β Amplifier 4 non-inverting input |
| Pin 13 | IN4- β Amplifier 4 inverting input |
| Pin 14 | OUT4 β Amplifier 4 output |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this component. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
LM324 is suitable for 6 applications: Transducer Amplifiers, DC Gain Blocks, Active Filters, Comparators and Oscillators, Battery-Powered and Portable Devices, Maker and Educational Electronics.
Transducer Amplifiers
The LM324 is explicitly recommended by TI and ST datasheets for transducer amplifier front ends. Its common-mode input range includes ground, so bridge and single-ended sensors can be read directly on a single supply without negative bias circuitry. With four amplifiers per package, multi-channel sensor arrays need only one IC for four conditioning stages, cutting BOM cost. The DC-accurate gain of the internally compensated stages suits slow-varying sensor outputs such as pressure, temperature, and light sensors; output headroom near the positive rail should be respected when setting gain.
Recommended
DC Gain Blocks
As a DC gain block, the LM324 provides four high-gain, internally frequency-compensated stages in one package. Per the onsemi datasheet, quiescent current is about one-fifth of the MC1741 per amplifier, which suits battery-powered instrumentation amplifying DC or low-frequency signals. Gain is set with two resistors per stage up to the unity-gain-stable limit; the ground-sensing input permits level shifting of ground-referenced signals on a single supply. Verify offset voltage drift for high-accuracy designs, where the LM324A or LM324B grades offer tighter specifications.
Recommended
Active Filters
Active low-pass, band-pass, and Sallen-Key filters are a classic LM324 application: one package implements a complete four-op-amp state-variable or multi-stage filter. The internal frequency compensation ensures unity-gain stability, and the 3V-32V single-supply range allows filtering of ground-referenced signals in 5V, 12V, or 24V systems. Because the LM324 gain-bandwidth is modest, filter corner frequencies should stay well into the tens of kHz; higher-frequency filters should use faster pin-compatible upgrades such as the LMC660, which drops into the same 14-pin footprint.
Recommended
Comparators and Oscillators
The LM324 is widely used as a quad comparator or relaxation oscillator in hobby, appliance, and industrial boards. Running from a single 3V-32V supply with inputs that sense ground, one package provides four threshold detectors or oscillator stages. The onsemi datasheet documents these circuits in its typical applications section. Designers should note that the LM324 is not a dedicated comparator - response is slower and output is optimized for linear swing - so fast edge detection should instead use true comparator ICs, keeping the LM324 for lower-speed thresholds.
Recommended
Battery-Powered and Portable Devices
Low per-amplifier quiescent current - about one-fifth of a 741 - plus operation down to 3.0V makes the LM324 a staple in battery-powered instruments and portable equipment. Four op amps share a single supply pin, minimizing board area and supply complexity in multi-channel portable designs such as meters and sensor loggers. Because output swing stops well short of the positive rail, designers maximize dynamic range by selecting supply voltages with adequate headroom or switching to rail-to-rail equivalents where the full 0-to-V+ output span is required.
Recommended
Maker and Educational Electronics
Arduino and maker platforms frequently use the LM324 for multi-channel analog conditioning because it is inexpensive, through-hole friendly (LM324N PDIP-14), available everywhere, and tolerates 5V single-supply prototyping with ground-sensing inputs. Common projects include sensor amplifiers, LED level indicators, audio mixers, and oscillator experiments. Its forgiveness of supply variation (3V-32V) and wide availability across TI, onsemi, and STMicroelectronics makes it an ideal teaching part; students should still observe its bandwidth and positive-rail output headroom limits.
Recommended
Recommended Products Summary
Engineering reference data for LM324 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LM324A | LM324B | LM2902 | LMC660 | LM324 (onsemi) |
|---|---|---|---|---|---|---|
| Package | 14-PDIP (LM324N) | 14-PDIP/SOIC - same pinout | 14-PDIP/SOIC - same pinout | 14-PDIP/SOIC - same pinout | 14-PDIP/SOIC - same pinout | 14-PDIP - same pinout |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | onsemi |
| Channels | 4 | 4 | 4 | 4 | 4 | 4 |
| Single Supply Range | 3 V to 32 V | 3 V to 32 V | 3 V to 32 V | 3 V to 26 V (grade-dependent) | 3 V to 16 V | 3.0 V to 32 V |
| Input Offset Voltage Grade | Standard | Tighter (A-grade) | Improved (B-grade) | Standard | CMOS, very low input bias | [DATA_NEEDED] |
| Temperature Range | Commercial/industrial standard | [DATA_NEEDED] | Wider than standard per TI | Extended automotive/industrial | [DATA_NEEDED] | [DATA_NEEDED] |
| Relative Cost (1ku) | Low (baseline) | Low, slightly higher | Lower 1ku price per TI comparison | Low | Higher | Low |
| Special Feature | Industry-standard multi-source quad | Precision grade | Drop-in performance upgrade | Automotive grade | Higher bandwidth, high Zin | Second-source supply security |
Key Differentiators
- Ground-sensing input on single supply (vs LMC660)
- Improved-grade drop-in upgrade available (vs LM324B)
- Automotive-temperature drop-in (vs LM2902)
Design Notes
The LM324 output cannot swing to the positive rail: reserve roughly 1.5V of headroom (more at heavier load) when setting signal ranges or comparator thresholds on single-supply designs. Also note the output stage can invert behavior when inputs exceed the common-mode range in unusual configurations - keep inputs within 1.5V of V+ to guarantee linear operation.
Decouple V+ (pin 4) with a 100nF ceramic capacitor placed close to the pin, especially when all four amplifiers drive loads simultaneously, since shared supply and ground nodes can couple stages. In dual-supply use, bypass both rails. The ground/V- pin (pin 11) carries the combined quiescent and load currents of all four amplifiers, so use a solid, low-impedance ground connection.
The LM324 gain-bandwidth and slew rate are modest, so it is suited to DC through tens of kHz. For higher-frequency filters, faster comparators, or audio-grade paths, use the pin-compatible LMC660 upgrade or OPA4134 for audio. Second-sourcing is trivial: onsemi and STMicroelectronics LM324 parts share the identical 14-pin pinout and can be substituted without PCB changes.
Compliance Information
RoHS compliance per TI/DigiKey product listings. For AEC-Q100 requirements use the related LM2902 automotive family.
