LM393P3 - Dual Open-Collector Comparator | Texas Instruments
MPN： LM393P3 ✓ 啟用中LM393P3 概覽
A comparator is a linear integrated circuit that evaluates two input voltages and produces a logic-level result indicating which input is higher. In the LM393, two comparators share a common supply and ground while retaining separate non-inverting, inverting, and output connections. This dual-channel architecture belongs to the comparator IC hierarchy, where the LM393 occupies the general-purpose, low-power, open-collector segment of the broader analog and power-management semiconductor category.
The principal engineering benefit is the open-collector output architecture. Unlike a totem-pole output, an open collector does not actively drive the output high, allowing a pull-up resistor to establish the high logic level. This supports wired-open-collector or wired-AND behavior, permits different supply domains for the pull-up rail, and requires an external pull-up on every output used in a design. The two channels can therefore implement independent threshold decisions, window detection, or complementary comparisons.
The LM393P3 uses the standard LM393 differential-comparator architecture rather than rail-to-rail input stages. Input behavior must therefore be evaluated against the device's common-mode and differential input limits in the manufacturer datasheet, especially when comparing signals near either supply rail. Because the verified records do not provide numerical input-offset, response-time, input-bias-current, output-sink-current, or channel-separation figures, those values require confirmation in the official LM393 datasheet before precision timing or sensing decisions are finalized.
Typical uses include industrial sensor thresholding, overvoltage and undervoltage detection, battery monitoring, control-loop signal comparison, and digital-interface adaptation. A practical application places the signal under test on one input and a reference voltage from a divider on the other; the open-collector output then changes state when the relation between the two voltages changes. A pull-up resistor converts the output state to a valid logic voltage, while hysteresis can reduce repeated switching when a slowly changing input crosses the reference.
For a new design, verify the required output current, input range, temperature grade, and logic compatibility against the datasheet before releasing the schematic. Do not omit the output pull-up resistors, and do not assume that the open collector can source current. Check whether a logic-family or application-specific comparator offers lower offset, faster response, rail-to-rail input operation, push-pull outputs, or automotive qualification. This page combines the verified product records with package, sourcing, comparison, and design guidance focused on drop-in replacement decisions.
直接替換替代品，適用於 LM393P3 — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： LM393P3 （相同外形與佔位） — 差異在於 Comparator Type, Output Type, Package, Operating Temperature Range, RoHS Status.
LM393P
✅ 直接替換聯絡詢價
查看資料表 →LM393N
✅ 直接替換聯絡詢價
查看資料表 →LM393BP
✅ 直接替換📋 參考替代品（不在目錄中）
LM393P3 最大額定值與電氣特性
| Comparator Type | Dual differential comparator |
| Number of Channels | 2 channels |
| 輸出類型 | Open collector |
| Supply Voltage Range | 2 V to 30 V |
| 工作溫度範圍 | 0 °C to 70 °C |
| Application Grade | Commercial grade |
| 封裝 | 8-PDIP |
| 腳位數 | 8 pins |
| 安裝類型 | Through-hole |
| Logic Compatibility | TTL, MOS, and CMOS compatible |
| Common-Mode Input Voltage Range | Includes ground |
| Differential Input Voltage Range | Equal to maximum-rated supply voltage |
LM393P3 8-pdip 腳位配置指南
LM393P3（8-pdip 封裝）的腳位配置。 此類比元件具有輸入、輸出與電源腳位。偏移歸零、補償與致能腳位配置請參閱製造商資料表。適用於訊號調理與放大器電路。
無詳細腳位定義資料： LM393P3.
請參閱 資料表 以查看完整腳位配置。
典型應用
LM393P3 適用於 6 應用s: Industrial Sensor Threshold Detection, Battery Voltage Monitoring, Overvoltage and Undervoltage Protection, Open-Collector Alarm Interface, Motor Control and Feedback Comparison, Digital Logic Level Adaptation.
Industrial Sensor Threshold Detection
The LM393P3 fits industrial sensor thresholding because it provides two independent differential comparison channels, open-collector outputs, and a 2 V to 30 V family supply range. A sensor-derived signal can be applied to one input while a resistor divider provides the reference to the other, allowing the comparator to indicate when the measured level crosses a defined threshold. The open collector requires a pull-up resistor, but that architecture also permits wired-open-collector signaling where multiple channels share a bus. Designers should confirm the input common-mode limits and output sink current in the official datasheet, particularly when the sensor output can approach the supply rails. Adding positive feedback creates adjustable hysteresis and reduces repeated output transitions around a noisy or slowly changing threshold.
推薦
Battery Voltage Monitoring
The LM393P3 is suitable for basic battery or DC-rail monitoring because its two comparison channels can independently evaluate upper and lower thresholds. Each channel can compare a divided battery voltage against a reference, while the open-collector outputs provide usable fault or status indications after pull-up. The LM393 family's 2 V to 30 V supply classification provides useful range for industrial battery systems, although the monitored input voltage and each comparator input must remain within the datasheet's common-mode limits. In an alarm implementation, the two outputs may be combined using wired-open-collector logic to indicate undervoltage, overvoltage, or an invalid battery state. Thermal design remains modest for the DIP package, but the actual dissipation depends on supply voltage, load, and the output state.
推薦
Overvoltage and Undervoltage Protection
The LM393P3 can implement independent overvoltage and undervoltage decisions in equipment power-supply control. Two differential channels allow each rail or alarm limit to be compared against a reference derived from a precision divider, and their open-collector outputs can pull down a common status line or trigger external hardware. The 2 V to 30 V family supply range suits many industrial control rails, while the DIP package supports through-hole assembly and field serviceability. The main design constraint is that the input and output ratings must be checked for the actual transient environment. Protection circuits exposed to surge or inductive transitions may need input filtering and clamping beyond the basic comparator. Pull-up resistors should be selected to suit the required logic voltage, fault current, and bus capacitance.
推薦
Open-Collector Alarm Interface
The LM393P3 is well matched to open-collector alarm and fault interfaces because each channel can sink a logic signal rather than source current directly. A pull-up establishes the high state, and multiple open-collector outputs can be wired together so that any active alarm pulls the shared line low. This allows the dual comparator to combine two conditions without a dedicated logic gate, while the 8-PDIP package remains convenient for through-hole industrial assemblies. In practice, engineers must confirm that the combined sink current stays within the comparator's output-current rating and that the pull-up voltage is compatible with the receiving logic. The output-low voltage also becomes part of the interface budget, so the receiver should use a suitable threshold. Pull-up resistor selection balances power consumption, rise time, bus capacitance, and fault-current capability.
推薦
Motor Control and Feedback Comparison
The LM393P3 can compare command and feedback signals in basic motor-control or actuator-feedback circuits, provided the signals remain within the comparator's input limits. The two channels can monitor opposite directions or compare a reference against a feedback-derived voltage, with open-collector outputs feeding a controller input or interlock stage. This arrangement is especially practical for low-cost commercial equipment where a DIP package and discrete pull-ups simplify service. The 2 V to 30 V supply range supports many control environments, but motor transients require careful routing and protection. Keep switching-node wiring away from comparator inputs, provide local bypassing, and use filtering or clamps where the feedback line can pick up noise. The open-collector topology requires a defined pull-up rail, and its pull-up value should be checked against the controller input capacitance and desired switching speed.
推薦
Digital Logic Level Adaptation
The LM393P3 can adapt a higher-voltage or floating signal to a logic family through its open-collector output and externally selected pull-up voltage. Although the comparator itself operates across a 2 V to 30 V family supply range, the output high level is determined by the pull-up rail rather than the comparator supply. This separation allows the output to match TTL, MOS, or CMOS-compatible logic levels when the input conditions are appropriate. The dual-channel implementation can adapt or combine two signals, and the wired-open-collector feature supports shared-bus signaling. Designers must verify the output saturation voltage at the intended sink current, the input common-mode range, and the logic family's input thresholds. Pull-up resistors should also be selected to maintain a valid rise time in noise and capacitive loading while limiting fault current.
推薦
推薦產品摘要
工程參考資料，適用於 LM393P3 — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | LM393P | LM393N | LM393BP |
|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 8-PDIP | 8-PDIP | 8-PDIP | 8-PDIP |
| Comparator Channels | 2 | 2 | 2 | 2 |
| Output Type | Open collector | Open collector | Open collector | Open collector |
| Logic Compatibility | TTL, MOS, and CMOS compatible | TTL, MOS, and CMOS compatible | TTL, MOS, and CMOS compatible | TTL, MOS, and CMOS compatible |
| Special Features | Standard LM393 family | Standard LM393 family | Standard LM393 family | Improved B-version specifications |
主要差異化特點
- Direct LM393-family replacement path in the same through-hole format (對比LM393P)
- Improved B-version option without changing the core open-collector interface (對比LM393BP)
- Broad family supply range for commercial control systems (對比LM393N)
設計說明
Do not treat an open-collector output as a push-pull logic output. Every used output requires an external pull-up resistor, and the circuit must not depend on the comparator sourcing output current. When multiple outputs are connected to one node, confirm that the combined sink current remains below the applicable limit and that the receiving device interprets the wired-low condition correctly.
Keep comparator inputs short, route them away from switching nodes, and use local supply bypassing near the device. Slow sensor signals can cause repeated output transitions near the threshold, so add controlled positive feedback for hysteresis where appropriate. The resistor used for positive feedback must not alter the intended reference voltage or exceed the device's differential-input restrictions.
Select the pull-up rail and resistor together. A smaller resistor lowers the logic rise time and supports more sink current, but increases supply consumption and fault current. A larger resistor reduces power but can produce a slower rising edge. Check the receiver's input capacitance, maximum transition time, and required logic thresholds before fixing the pull-up value.
Place the input, output, and bypass components close to the appropriate IC pins. Use a short, direct return path to the supply ground, and keep comparator traces away from high-current switching paths. Because the package is a through-hole 8-PDIP, verify the physical pin numbering against the manufacturer diagram and the board footprint before fabrication; the supplied records do not provide a verified individual pin list.
合規資訊
The supplied verified records identify commercial-grade application, compatibility with TTL, MOS, and CMOS logic, and the family supply range, but they do not provide explicit RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals declarations. These fields remain unknown rather than being inferred.
