LM393NG - Dual Open-Collector Comparator, 36 V | onsemi
部品番号: LM393NG ✓ 生産中LM393NG 概要
A voltage comparator is an analog integrated circuit that compares two input voltages and produces a logic-level indication of their relationship. In the hierarchy of electronic components, the LM393NG is a dual comparator, part of the comparator and analog signal-conditioning family used between sensors, switching circuits, and digital logic. Because its open-collector outputs require an external pull-up resistor, the device can directly interface with TTL, CMOS, and MOS logic while remaining flexible in voltage and polarity.
The LM393NG's principal advantages are its two independent channels, low offset voltage of 2.0 mV, 250 nA input current specification, and ability to operate from a single supply or with split supplies. Its common-mode input range includes ground during single-supply operation, making it practical for battery-powered and low-side sensing systems. The open-collector architecture also permits the output transistor to remain off when the device is unpowered, subject to the detailed limits stated by the manufacturer.
Technically, the LM393NG combines independent comparator channels with output stages designed for wired-open-collector use. A pull-up resistor sets the output high state, while the comparator pulls the output low when its condition is met. Because the output is not actively driven high, output rise time depends on the pull-up resistance and the capacitance connected to the output node. Designers should therefore avoid excessive pull-up resistance when fast transitions or low propagation delay are important.
Typical uses include window monitoring for power rails, sensing battery voltage, comparing a sensor against a reference, detecting overtemperature, building simple oscillator and relay-drive circuits, and generating control signals for industrial or automotive equipment. Split-supply operation is useful where signals may be centered around ground, while single-supply operation supports systems whose available inputs remain between ground and the positive supply.
The main PCB considerations are correct orientation, adequate bypassing near the supply pins, and unobstructed pull-up access at each open-collector output. Confirm input common-mode limits, output-current capability, and absolute maximum ratings against the manufacturer datasheet before applying the comparator outside nominal supply conditions. Keep sensitive feedback networks away from switching-node and high-current return paths to avoid offset errors and unstable switching behavior.
This page combines the verified onsemi, DigiKey, and Mouser product information with practical comparator-selection guidance, same-package alternatives, and design notes intended to make LM393NG sourcing and implementation decisions more efficient than a basic distributor listing alone.
ドロップイン代替品: LM393NG — 同一パッケージでピン互換。PCBの作り直しが必要な異なるパッケージの部品は除外されています。
このシリーズのバリエーション
同一シリーズでドロップイン互換のモデル: LM393NG （同一形状・フットプリント） — 相違点: Package, Output Type, Comparator Type, RoHS Status.
LM393N
✅ ドロップイン価格はお問い合わせください
データシートを見る →LM393P
✅ ドロップイン価格はお問い合わせください
データシートを見る →LM393AD
✅ ドロップイン価格はお問い合わせください
データシートを見る →LM2903M
✅ ドロップイン価格はお問い合わせください
データシートを見る →LM393NG 最大定格＆電気的特性
| Comparator Count | 2 independent comparators |
| Product Type | Precision voltage comparator |
| Supply Voltage Range | 2 V to 36 V |
| 出力タイプ | Open-collector |
| パッケージ | 8-pin PDIP |
| 実装タイプ | Through-hole |
| Input Offset Voltage | As low as 2.0 mV |
| Input Current | 250 nA |
| Differential Input Voltage Range | -38 V to +38 V |
| Single-Supply Operation | Supported |
| Split-Supply Operation | Supported |
| Single-Supply Common-Mode Range | Includes ground |
| Temperature Grade | Commercial |
| Logic Compatibility | TTL, MOS, and CMOS compatible |
LM393NG ピン構成
| ピン 1 | OUT1 — Channel 1 open-collector output |
| ピン 2 | IN1- — Channel 1 inverting input |
| ピン 3 | IN1+ — Channel 1 non-inverting input |
| ピン 4 | GND — Ground reference |
| ピン 5 | IN2+ — Channel 2 non-inverting input |
| ピン 6 | IN2- — Channel 2 inverting input |
| ピン 7 | OUT2 — Channel 2 open-collector output |
| ピン 8 | VCC — Positive supply input |
主な用途
LM393NG の用途: 6 件s: Power-Supply Window Monitoring, Battery Voltage Sensing, Temperature Threshold Detection, Industrial Sensor Interface, Relay and Solenoid Drive, Oscillator and Relay Logic.
Power-Supply Window Monitoring
The LM393NG is suitable for monitoring a battery or regulated rail because its two independent comparator channels can establish upper and lower voltage thresholds. According to the onsemi LM393 documentation, the device operates from 2 V to 36 V and provides input offset voltage as low as 2.0 mV, allowing threshold selection with relatively low error. Each open-collector output can pull down a separate logic or fault line while an external pull-up establishes the high state. In a dual-cell or industrial supply monitor, one channel can detect an upper threshold and the other a lower threshold, creating a window fault indication. Resistor tolerance and the comparator's actual offset across temperature should be included in worst-case threshold calculations.
おすすめ
Battery Voltage Sensing
The LM393NG can detect a low-battery condition by comparing a scaled battery voltage against a reference level. According to the onsemi LM393 family documentation, its 2 V minimum supply and single-supply common-mode range extending to ground make it appropriate for low-side battery sensing. The open-collector output can directly pull a pull-up-backed input on a low-power microcontroller, avoiding a continuously driven high state. Divider resistance should be selected to balance input-current error against supply consumption, while the 2.0 mV minimum offset specification provides a useful starting point for precision analysis. Designers should also verify battery transients, cold-temperature behavior, and the comparator's allowed input range before applying it directly to a live pack.
おすすめ
Temperature Threshold Detection
The LM393NG can implement a two-level thermal alarm by comparing temperature-sensor outputs with independently generated reference voltages. According to the onsemi LM393 product information, the device provides two independent precision comparators and an input offset voltage specified as low as 2.0 mV, which supports narrow threshold spacing when component tolerances are controlled. One open-collector output can signal an overtemperature condition to a fan driver or system controller, while the other can provide warning or hysteresis. Open-collector outputs permit wired logic and straightforward pull-up selection, but external hysteresis is needed to prevent oscillation near the threshold. Confirm the sensor slope, accuracy, noise, and full operating-temperature range before using the LM393NG in safety-critical thermal protection.
おすすめ
Industrial Sensor Interface
The LM393NG provides a simple discrete interface when a sensor produces an analog voltage that must be converted into a digital threshold event. According to the onsemi LM393 family datasheet, the comparator supports single and split supplies, accepts a common-mode range including ground in single-supply operation, and uses open-collector outputs compatible with common logic families. Conditioning the sensor with a resistor network or amplifier can reduce error caused by the comparator's input bias and offset. The external pull-up should be sized for the required logic voltage and sink-current budget, while additional filtering may be necessary near noisy industrial wiring. For systems requiring a signed signal around ground, split-supply operation can simplify the comparison, but common-mode and differential input limits must be respected.
おすすめ
Relay and Solenoid Drive
The LM393NG can act as the decision stage in a relay or solenoid driver because its open-collector output is designed to sink the coil-control current when external circuitry provides the drive path. According to the onsemi LM393 family documentation, the output supports common logic systems and operates across a 2 V to 36 V supply range. The comparator may be paired with a suitable transistor or MOSFET so that the IC does not exceed its output-current limits. A flyback diode is normally required for an inductive load, subject to the load and driver topology. Because the open-collector output has no active high drive, a pull-up or interface resistor must be included. Verify output-current, voltage, and power limits from the manufacturer datasheet before finalizing the driver stage.
おすすめ
Oscillator and Relay Logic
The LM393NG can be used as one element of a simple oscillator, retriggerable timer, or relaxation-based relay circuit. According to the LM393 family information, its two channels are independent and its open-collector outputs permit passive feedback networks and wired logic connections. A resistor-capacitor timing network can establish a switching interval, while the second channel may provide buffering or an alternate threshold event. Component tolerances and comparator propagation delay can materially affect the resulting frequency, so the timing calculation must include both. The open-collector output also requires a pull-up, and its finite transition behavior can influence the duty cycle. Use this approach for noncritical timing or simple control functions, and select a dedicated timer when precise frequency accuracy is required.
おすすめ
おすすめ製品の概要
エンジニアリング参考データ: LM393NG — 比較、設計ガイダンス、コンプライアンス情報。
選定ガイド
代替品との比較
| パラメータ | この製品 | LM393N | LM393P | LM393AD | LM2903M |
|---|---|---|---|---|---|
| Package | 8-pin PDIP | 8-pin PDIP | 8-pin PDIP | 8-pin PDIP | 8-pin PDIP |
| Brand | onsemi | onsemi | Texas Instruments | Texas Instruments | Texas Instruments |
| Comparator Count | 2 independent comparators | 2 independent comparators | 2 independent comparators | 2 independent comparators | 2 independent comparators |
| Output Type | Open-collector | Open-collector | Open-collector | Open-collector | Open-collector |
| Mounting Type | Through-hole | Through-hole | Through-hole | Through-hole | Through-hole |
主な差別化要因
- Two genuinely independent comparator channels in one package （vs LM2903M)
- Low documented input offset voltage （vs LM393AD)
- Single-supply common-mode operation reaches ground （vs LM393P)
- Wide single and split-supply operating range （vs LM393N)
設計ノート
Place the supply-bypass capacitor close to pin 8 and connect it to the ground reference with a short return path. The verified LM393 family information supports operation from 2 V to 36 V, but it does not provide a recommended capacitance value in the supplied excerpts. Select the capacitor and routing using the manufacturer datasheet and board-level noise requirements. Keep the comparator ground reference electrically quiet and avoid sharing narrow return paths with relay, motor, or switching-converter currents.
Do not treat the open-collector output as a push-pull logic output. It can sink current when asserted, but a pull-up resistor is required to produce the high state. Choose the resistor to satisfy the input current of the following logic device while keeping sink current within the LM393NG output rating. Also verify the input common-mode range for both supply configurations; the verified single-supply description says that the range includes ground but does not state every numeric limit.
For precision threshold comparisons, account for input bias current, input offset voltage, resistor tolerance, and noise on both inputs. The verified source states an input offset voltage as low as 2.0 mV and an input current of 250 nA, but these are not guaranteed final design errors across every temperature and common-mode condition. Use the manufacturer worst-case tables for production limits. Keeping the two input traces short and away from switching nodes reduces differential noise pickup.
Preserve access to all eight PDIP pins and maintain adequate spacing around the package for soldering and inspection. Because the two channels are independent, their input networks may be physically separated on the board, but shared references should remain low impedance. Label pin 1 clearly and verify the PDIP orientation against the manufacturer drawing. If the outputs drive multiple loads through pull-ups, calculate the worst-case aggregate sink current rather than checking each output in isolation.
コンプライアンス情報
The verified sources mention automotive applications but do not explicitly provide LM393NG RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals declarations. Formal compliance must be confirmed from current onsemi documentation.