LM2903M - Dual Differential Comparator | Texas Instruments
部品番号: LM2903M ✓ 生産中LM2903M 概要
A comparator is a differential amplifier with a logic output rather than a conventional analog output. It evaluates the voltage relationship between its inverting and non-inverting inputs and produces a saturated digital state when the selected input exceeds the reference. In the LM2903M, two independent channels allow one device to perform two threshold decisions, window comparisons, or complementary sensing functions. This makes the part useful as a building block within logic ICs, interface ICs, industrial control systems, and discrete analog signal-conditioning circuits.
Key features include dual differential comparison, an open-collector output, single-supply operation from 2 V to 36 V, support for split-supply operation, and an 8-SOIC surface-mount package. The open-collector outputs can be wired to a common pull-up rail when multiple comparators need a shared bus, although the pull-up resistor and external logic voltage must be selected for the intended interface. The reported 1.5 microsecond response time is adequate for many industrial and control applications where the system does not require sub-microsecond decisions.
The LM2903 family is designed for low-power operation independent of the supply voltage, which helps conserve energy in battery-powered and distributed equipment. Each channel has independent input and output behavior, allowing one channel to monitor a sensor while the second channel provides an alarm, window-limit, or control function. Input and output behavior should still be checked against the complete manufacturer datasheet for the exact ordering code before production use.
Typical applications include battery monitoring, industrial sensor interfaces, overvoltage and undervoltage detection, temperature threshold circuits, power-supply sequencing, and general-purpose logic control. The open-collector output is especially useful when driving a relay, opto-isolator, or another device that requires a pulled-up supply domain. The SOIC-8 footprint is suitable for conventional surface-mount PCB assembly, but the exposed package dimensions and lead geometry should be checked against the mechanical drawing.
For a reliable design, begin by verifying the input common-mode range, output sink current, supply-current limits, and propagation delay against the required operating conditions. Do not leave the open-collector outputs without an appropriate pull-up resistor unless the intended load provides one. Decoupling capacitors should be placed close to the supply and ground pins, and input traces should be kept short to reduce noise pickup. This product page combines verified manufacturer and distributor information with engineering guidance, comparison data, and practical design notes to support component selection and PCB implementation.
ドロップイン代替品: LM2903M — 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: LM2903M （同一形状・フットプリント） — 相違点: Comparator Type, Mounting Type, Number of Comparators, Operating Temperature Range, Output Type.
LM2903M/NOPB
✅ ドロップイン📋 参考代替品（カタログ未掲載）
LM2903-N
✅ ドロップイン📋 参考代替品（カタログ未掲載）
LM2903DRG4
✅ ドロップイン📋 参考代替品（カタログ未掲載）
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 →LM2903N
✅ 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 最大定格＆電気的特性
| Comparator Type | Dual differential comparator |
| Number of Comparators | 2 |
| Supply Voltage Range | 2 V to 36 V |
| 出力タイプ | Open-collector |
| Input Common-Mode Capability | Rail-to-rail |
| Propagation Delay | 1.5 microseconds |
| 電源電流 | 1 mA |
| Output Compatibility | CMOS, DTL, ECL, MOS, TTL |
| パッケージ | 8-pin SOIC |
| 実装タイプ | Surface mount |
| ピン数 | 8 pins |
| Operating Supply Modes | Single supply or split supply |
| 動作温度範囲 | -40 C to +85 C |
LM2903M 8-pin soic ピン配置ガイド
LM2903M (8-pin soic パッケージ) のピン配置。 このアナログコンポーネントは、入力、出力、および電源ピンを備えています。オフセットナル、補償、イネーブルピンの設定については、メーカーのデータシートを参照してください。信号調整やアンプ回路に最適です。
詳細なピン配置データはありません: LM2903M.
詳細は データシート をご参照ください。
主な用途
LM2903M の用途: 6 件s: Battery Voltage Monitoring, Industrial Sensor Threshold Detection, Overvoltage and Undervoltage Protection, Power Supply Sequencing, LED and Relay Drive Logic, Temperature and Level Limit Detection.
Battery Voltage Monitoring
The LM2903M is suitable for battery voltage monitoring because its two independent differential comparators can evaluate two thresholds in one 8-SOIC package. The 2 V to 36 V single-supply range supports a broad range of industrial and portable-system rails, while the open-collector outputs can drive alarm or power-management logic through pull-up resistors. A typical implementation compares a divided battery signal with precise references at each channel and provides a fault indication when the rail falls outside the acceptable window. The 1.5 microseconds propagation delay is more than sufficient for ordinary battery-state monitoring. Designers should confirm that the divided input remains within the comparator's common-mode range and select pull-up values that satisfy both the downstream input and output sink-current limits.
おすすめ
Industrial Sensor Threshold Detection
The LM2903M fits industrial sensor threshold detection where a sensor signal must be converted into a logic decision. One channel can monitor an upper threshold and the other a lower threshold, enabling a window comparator without two separate ICs. Its rail-to-rail input capability, 1 mA-class supply current, and 1.5 microseconds response time support straightforward supervision of thermistors, potentiometers, and resistive sensor networks. Because the outputs are open collector, pull-ups can connect the comparator to the system logic voltage while allowing wired alarm signals. The design must ensure that the sensor excitation and input signal remain within the LM2903M's input limits and that pull-up resistance avoids excessive switching current.
おすすめ
Overvoltage and Undervoltage Protection
The LM2903M can implement overvoltage and undervoltage protection by assigning one comparator channel to each rail limit. The 2 V to 36 V operating range is particularly useful in systems whose monitored supply can exceed the logic supply, while the open-collector outputs provide a simple way to disable a regulator, load switch, or downstream circuit. A divided feedback signal and precision reference determine the switching point, so resistor accuracy and reference stability directly affect protection accuracy. The dual-channel arrangement reduces package count compared with two separate single comparators. The trade-off is that the open-collector outputs require suitable pull-up arrangements and cannot directly source current, while the 1.5 microsecond delay is appropriate for protection rather than high-speed fault containment.
おすすめ
Power Supply Sequencing
The LM2903M is applicable to simple power-supply sequencing when each rail is compared with a reference or divided feedback voltage. One channel can supervise a primary rail and the other can monitor a dependent rail, producing open-collector signals that enable regulators in the required order. The wide single-supply capability allows the comparators to operate from the same rail family as the system, and the 1.5 microseconds response is adequate for sequencing intervals measured in milliseconds. Engineers should account for the fact that open-collector outputs sink current rather than source it, so external pull-ups and any required inversion logic must be included. The application is best suited to simple threshold control rather than precise load-sharing or fast digital power-management loops.
おすすめ
LED and Relay Drive Logic
The LM2903M can provide low-side threshold logic for LED indicators, relay drivers, and other discrete loads when the load is connected to a pull-up supply. Its open-collector output pulls the load node down when the comparison result changes, making it convenient for fail-safe alarm wiring and shared logic buses. The two channels permit separate indication or control functions, such as a relay-release signal and a status LED. The output stage must be checked against the required sink current, and a flyback diode is required for inductive relay loads unless protection is otherwise provided. Compared with a push-pull output, the open-collector architecture requires an external pull-up but gives greater flexibility when interfacing to another voltage domain.
おすすめ
Temperature and Level Limit Detection
The LM2903M is useful for temperature and level limit detection when a sensor or resistive divider produces a voltage proportional to the measured condition. One comparator can detect an upper alarm and the second can detect a lower alarm, creating an independent limit channel without adding another IC. The 1.5 microseconds propagation delay provides quick response to slow thermal and liquid-level changes, while the low supply-current characteristic supports power-conscious instrumentation. The output pull-up should be selected so the comparator can sink the required current and the interface voltage remains compatible. Input offset voltage, reference accuracy, and sensor lead resistance determine the practical trip-point accuracy, so those values should be evaluated against the manufacturer data.
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: LM2903M — 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 | LM2903M/NOPB | LM2903-N | LM2903DRG4 | LM2903M | LM2903N |
|---|---|---|---|---|---|---|
| Package | 8-SOIC | 8-SOIC - same | 8-SOIC - same | 8-SOIC - same | 8-SOIC - same | 8-SOIC - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | onsemi | NXP Semiconductors |
| Comparator Type | Dual differential comparator | Dual differential comparator | Dual differential comparator | Dual differential comparator | Dual differential comparator | Dual differential comparator |
| Number of Comparators | 2 | 2 | 2 | 2 | 2 | 2 |
主な差別化要因
- Two independent comparator channels in one 8-SOIC package （vs LM2903M/NOPB)
- Wide single-supply operating range （vs onsemi LM2903M)
- Open-collector interface flexibility （vs LM2903N)
設計ノート
Do not treat an open-collector output as a push-pull logic output. Provide a suitable pull-up resistor on each output unless the downstream circuit already contains one. The pull-up voltage defines the logic-high level, while the resistor value determines the sink current and rise time. Verify the maximum output sink current and ensure that the connected bus remains within the device's voltage limits.
Place the input and output traces close to the relevant pins and route them away from high-current switching nodes. The LM2903M's two channels should have separate input paths when their thresholds or signals are unrelated, because shared copper or signal coupling can create offset errors and false switching. Keep the supply decoupling capacitor close to the supply and ground pins, and use a low-impedance ground reference for the comparator circuit.
The verified supply-current listing is 1 mA, but actual system consumption depends on the device version, supply voltage, output state, and pull-up network. When comparing alternatives, confirm the datasheet operating current rather than assuming that every LM2903-family manufacturer has identical consumption. Also verify the absolute maximum supply voltage before transients or inductive coupling could appear at the input pins.
The listed 1.5 microseconds propagation delay is appropriate for ordinary threshold decisions but not for high-speed pulse qualification or precision timing loops. If the input crosses the threshold slowly, noise near the trip point can cause repeated output transitions; add suitable hysteresis with positive feedback or use a faster comparator when the application requires clean, rapid transitions.
コンプライアンス情報
The supplied verified web results do not explicitly state RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals status for LM2903M. These values remain unknown rather than being inferred from the manufacturer name or device category.
