LM393ST - Dual Open-Collector Comparator | STMicroelectronics
料号： LM393ST ✓ 量产中LM393ST 概述
A voltage comparator is an analog integrated circuit that compares two input voltages and changes its output state when the non-inverting input exceeds the inverting input, or vice versa. Within the broader semiconductor hierarchy, a comparator belongs to the amplifier and signal-conditioning IC family, where it supports threshold detection, decision-making, and feedback control. Unlike a general-purpose operational amplifier, the LM393ST uses open-collector outputs designed for wired logic, pull-up arrangements, and low-voltage system interfacing.
Each LM393ST channel includes an open-collector output capable of sinking current while remaining in a high-impedance state when inactive. External pull-up resistors establish the high output level, allowing the device to interface with a selected supply voltage and potentially support open-collector bus arrangements. The dual-channel configuration provides two independent comparators in one package, reducing board area when a design requires more than one threshold decision.
The LM393 family is specified for operation from 2 V to 36 V on a single supply, while the STMicroelectronics listing describes rail-to-rail input behavior. This wide supply range accommodates low-voltage control systems as well as industrial environments operating from higher rails. The open-collector outputs and broad input capability make the device useful for monitoring supply rails, detecting sensor crossings, implementing window functions with additional circuitry, and building basic automation-control decisions.
Because the outputs are open collector, every board-level implementation must include suitable pull-up components unless the outputs are connected to another compatible open-collector load. The pull-up voltage should remain within the electrical limits of the connected logic, while the pull-up resistance must balance rise time, power consumption, and output-current capability. Short traces and a common ground reference help prevent comparison errors when sensing small voltage differences.
Use the LM393ST when two independent, general-purpose comparisons are needed in an 8-pin MiniSO design and open-collector interfacing is desirable. Review the manufacturer pin description and electrical limits before final PCB routing, particularly input common-mode range, output sink current, supply sequencing, and exposed thermal behavior.
直接替换替代料： LM393ST ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
LM393ST 最大额定值与电气特性
| Comparator Type | Dual general-purpose voltage comparator |
| Number of Channels | 2 channels |
| 输出类型 | Open-collector |
| Input Common-Mode Capability | Rail-to-rail |
| Single-Supply Operating Voltage | 2 V to 36 V |
| Maximum Supply Voltage | 36 V |
| 封装 | 8-MiniSO |
| 引脚数量 | 8 pins |
| 安装类型 | Surface mount |
| Automotive Qualification | Not applicable |
| RoHS 状态 | ROHS3 compliant |
LM393ST 8-miniso 引脚配置指南
LM393ST（8-miniso 封装）的引脚配置。 该模拟元件具有输入、输出和电源引脚。请参阅制造商数据手册以了解失调调零、补偿和使能引脚配置。适用于信号调理和放大器电路。
暂无详细引脚数据： LM393ST.
请参阅 数据手册 以查看完整引脚配置。
典型应用
LM393ST 适用于 6 应用s: Industrial Sensor Threshold Detection, Power-Supply Overvoltage Detection, Motor and Actuator Control, Battery Threshold Protection, Automated Equipment Logic, Communications and Network Equipment.
Industrial Sensor Threshold Detection
The LM393ST suits industrial sensor interfaces that require two independent threshold decisions within a compact 8-MiniSO footprint. Each channel can compare a conditioned sensor voltage with a reference, while the open-collector output provides a pulled-down fault event or pulled-high ready state through an external resistor. The 2 V to 36 V single-supply range supports both compact control electronics and higher industrial rails. Design protection around exposed sensor wiring, validate the selected temperature grade, and choose pull-up values that satisfy the required logic rise time without excessive continuous power.
推荐
Power-Supply Overvoltage Detection
The LM393ST can monitor a divided power rail against a reference and provide an open-collector fault indication when the monitored voltage crosses a defined limit. Its 2 V to 36 V operating range is useful across multiple supply architectures, and rail-to-rail input behavior supports direct sensing near the supply rails when the input limits permit. A fault signal can drive a system shutdown or status latch through a pull-up resistor. Resistor tolerance, input bias effects, and propagation delay determine threshold accuracy, so include those effects in the safety-margin calculation.
推荐
Motor and Actuator Control
The two channels in the LM393ST can support independent limit decisions in motor, valve, or actuator-control circuits. One channel may monitor a command or feedback signal while the other evaluates a position, speed, or travel limit, producing open-collector events for a controller or driver stage. The 8-MiniSO package keeps the sensing section compact, while the wide single-supply range accommodates industrial control systems. Relay, motor, and actuator transients require external protection because the comparator is intended for signal conditioning and logic-level decisions, not direct high-energy load driving.
推荐
Battery Threshold Protection
The LM393ST is applicable to battery systems that need early warning when a cell or rail approaches a defined limit. Its family operates from 2 V on a single supply, and the two channels can monitor charge and discharge thresholds without requiring two packages. Open-collector outputs allow pull-ups to the logic rail used by the battery controller. Divider resistance should balance battery drain against input bias error, while the selected resistor and source qualification should be checked for temperature and leakage effects. Accurate protection requires checking the actual cell range against the comparator's input and supply limits.
推荐
Automated Equipment Logic
The LM393ST can implement discrete limit checks and interlock decisions in automated equipment where two comparator functions are needed close to a connector or control board. Each open-collector output can participate in a wired logic condition, allowing a single fault line to represent several limit states. The dual-channel 8-MiniSO arrangement reduces board area, while the 2 V to 36 V supply range provides design flexibility. For reliable operation, keep sensing traces short, maintain a low-impedance common ground, add filtering for noisy analog inputs, and verify the exact component's absolute maximum ratings against the machine's electrical environment.
推荐
Communications and Network Equipment
The LM393ST can provide receive-line threshold checks, supply-window detection, or fault qualification in communications equipment. Its two open-collector channels can monitor separate signal or rail conditions, and external pull-ups permit connection to the equipment's internal logic supply. The broad 2 V to 36 V range accommodates cards operating from low-voltage rails through higher industrial supplies. High-speed communications decisions may require a lower-delay comparator, so compare propagation delay before using this general-purpose device for timing-critical line coding. Add filtering and protection at externally accessible connectors.
推荐
推荐产品汇总
工程参考数据： LM393ST ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | LM393ST |
|---|---|---|
| Package | 8-MiniSO | 8-MiniSO |
| Brand | STMicroelectronics | ROHM Semiconductor |
| Comparator Configuration | Dual general-purpose comparator | Dual general-purpose comparator |
| Output Type | Open-collector | Open-collector |
| Input Common-Mode Capability | Rail-to-rail | Rail-to-rail |
| Number of Channels | 2 channels | 2 channels |
| Mounting Type | Surface mount | Surface mount |
关键差异点
- Matched package and comparator configuration （对比 LM393ST from ROHM Semiconductor)
- Broad single-supply operating range （对比 LM393LV from Texas Instruments)
- Two independent general-purpose channels （对比 Single-channel comparator alternatives)
设计说明
Place the LM393ST close to the signals being compared and provide a low-impedance ground return to minimize differential pickup and ground bounce. Keep the pull-up resistor near the corresponding output so the open-collector node has a short route to its receiver. When either input is connected through long wiring, add series resistance and input filtering at the connector rather than relying on the comparator alone to reject industrial noise.
The open-collector output does not require a dedicated high-voltage output driver, but every output node still needs a pull-up resistor. Choose the resistor to satisfy the receiver's rise-time requirement while keeping continuous dissipation within the resistor's rating. If the pull-up rail differs from the comparator supply, confirm that the resulting output-node voltage remains within the LM393ST's permitted limits.
Do not treat the open-collector output as a push-pull logic output. Without a pull-up, the output remains high-impedance after the sink transistor turns off, which can produce undefined voltage transitions in downstream logic. Also verify the manufacturer's pin map because the LM393ST ordering code is used by multiple manufacturers. Confirm input polarity, output assignments, supply pins, and grounding before fabricating the PCB.
A comparator output transitions when the differential input passes through its offset region, so slow or noisy input crossings can cause repeated output toggling. Keep the input network low impedance and use hysteresis through positive feedback when the application must avoid chatter. Select the hysteresis amplitude with enough margin to exceed input offset and noise while remaining inside the usable common-mode range.
合规信息
The component catalog identifies the device as ROHS3 compliant. REACH and moisture-sensitivity details are not stated in the catalog excerpts, and no automotive qualification is identified.
