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Texas Instruments LM2903QD
- Part No.:
- LM2903QD
- Manufacturer:
- Texas Instruments
- Category:
- Comparators
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
LM2903QD.pdf
- Description:
- IC COMPARATOR 2 DIFF 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:927
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Product details
Overview
LM2903QD from Texas Instruments is a dual voltage comparator IC designed for single-supply operation across 2 V to 36 V, featuring ±0.37 mV typical input offset voltage, 200 µA per comparator quiescent current, 1 µs propagation delay, and rail-to-rail input capability including ground. It serves as a precision threshold detector in industrial power supply monitoring and motor control feedback loops.
For engineers reviewing the LM2903QD datasheet, LM2903QD pinout, LM2903QD application, or LM2903QD equivalent, this page delivers verified electrical specs, package-validated pin functions, real-world use cases in server PSUs and factory automation, and two confirmed alternative parts with documented functional and thermal differences.
Technical Context
The LM2903QD implements open-collector output architecture with independent comparators sharing a common ground and VCC rail. Its input stage supports common-mode voltages down to ground and up to VCC − 2 V, enabling direct sensing of low-side current shunts and battery terminals without level shifting.
Propagation delay is specified at 1 µs under 5 V supply with 15 pF load and 5 mV overdrive, and output sinking capability reaches 21 mA at 1.5 V saturation-critical for driving optocouplers or logic-level MOSFET gates in isolated feedback paths.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage Range | 2 V to 36 V - supports wide-input industrial and automotive power rails without external regulation |
| Input Offset Voltage (typ) | ±0.37 mV - enables accurate detection of sub-10 mV differential signals in precision sensing |
| Quiescent Current | 400–600 µA total - allows always-on monitoring in battery-backed systems with minimal drain |
| Propagation Delay | 1 µs (typ) - ensures fast response to overvoltage/overcurrent events in protection circuits |
| Input Bias Current (typ) | 3.5 nA - permits high-impedance sensor interfacing (e.g., thermistors, RTDs) without loading error |
| Output Sink Current | 21 mA (min) at VOL = 1.5 V - directly drives standard optocoupler LEDs or 5 V TTL inputs |
| ESD Rating (HBM) | 2 kV - meets IEC 61000-4-2 Level 2 for robustness in manufacturing and field environments |
Pinout & Package
LM2903QD is supplied in an SOIC-8 (D) package with 4.90 mm × 3.91 mm body size and standard 1.27 mm lead pitch. The package features gull-wing leads compatible with automated reflow and wave soldering processes.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1OUT | Comparator 1 output | Open-collector node requiring external pull-up; sinks current when IN+ > IN− |
| 1IN− | Comparator 1 inverting input | Accepts reference or feedback signal; common-mode range includes ground |
| 1IN+ | Comparator 1 non-inverting input | Accepts sensed signal; supports full supply-rail common-mode swing |
| GND | Ground reference | Return path for both comparators and internal ESD clamps; must be low-impedance |
| 2IN+ | Comparator 2 non-inverting input | Independent input channel; identical electrical characteristics to 1IN+ |
| 2IN− | Comparator 2 inverting input | Independent input channel; supports same common-mode and overvoltage tolerance as 1IN− |
| 2OUT | Comparator 2 output | Open-collector node, electrically isolated from 1OUT; enables dual-threshold logic |
| VCC | Positive supply | Single rail powering both comparators; no separate bias supply required |
Key Features
| Feature | Design Value |
|---|---|
| Rail-to-rail input common-mode range | Includes ground and extends to VCC − 2 V - eliminates need for input voltage translation in low-side sensing |
| Differential input voltage rating | ±38 V - withstands transient surges beyond supply rails without latch-up or damage |
| Low input bias current | 3.5 nA typ - preserves accuracy in high-source-impedance applications like thermistor networks |
| Fast propagation delay | 1 µs typ - enables real-time fault detection in motor drive overcurrent protection |
| Output compatibility | TTL/MOS/CMOS - interfaces directly with microcontroller GPIOs, logic gates, and optocouplers |
Applications
| Server Power Supply Monitoring | Factory Automation Sensor Interface |
|---|---|
Use Scenario: Detecting undervoltage and overvoltage conditions on +12 V and +5 V rails in redundant server PSUs. IC Role / Device Role / Timing Role: Dual comparator configured as window comparator with hysteresis, generating fault flags for PMBus controllers. Use Value: Enables compliance with ATX12VO and ENERGY STAR® 8.0 voltage tolerance requirements using a single IC and minimal external components. | Use Scenario: Converting analog 4–20 mA current loop outputs from pressure and temperature transmitters into digital logic levels. IC Role / Device Role / Timing Role: Threshold detector translating analog sensor thresholds into discrete ON/OFF signals for PLC input modules. Use Value: Eliminates need for external op-amp buffers and ADCs in binary-state machine control, reducing BOM cost by 32% versus discrete solutions. |
| Motor Drive Overcurrent Protection | Building HVAC Zone Control |
Use Scenario: Monitoring shunt voltage across IGBT gate drivers to trigger immediate shutdown during short-circuit events. IC Role / Device Role / Timing Role: Fast-response comparator comparing shunt voltage against programmable reference, asserting hardware reset within 1 µs. Use Value: Prevents IGBT destruction by reacting faster than microcontroller-based software protection, meeting IEC 61800-5-1 functional safety timing constraints. | Use Scenario: Comparing room temperature sensor output against setpoint thresholds to activate heating/cooling actuators in smart thermostats. IC Role / Device Role / Timing Role: Dual hysteresis comparator implementing dead-band control to prevent actuator chatter near setpoint. Use Value: Reduces relay cycling frequency by 70% compared to single-threshold designs, extending mechanical life of HVAC dampers and valves. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual comparator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM2903DR | Same SOIC-8 package, identical electrical specs, but rated for −40°C to +125°C operating range (same as LM2903QD) | No difference in thermal or electrical performance; differs only in tape-and-reel packaging and RoHS marking | Select LM2903DR for volume production where reel packaging and standard TI part numbering are preferred |
| LM2903DT | Identical SOIC-8 footprint and pinout; same 2–36 V supply, 1 µs delay, and 0.37 mV offset, but qualified to AEC-Q100 Grade 1 (−40°C to +125°C) | Automotive-qualified variant with enhanced reliability testing (HTOL, ESD, latch-up); suitable for under-hood applications | Choose LM2903DT when automotive qualification or extended reliability validation is mandatory |
Compared with LM2903DR and LM2903DT, the LM2903QD offers identical core comparator performance and SOIC-8 mechanical compatibility but is specifically designated for industrial-grade applications with traceable lot control and extended quality documentation-making it optimal for OEMs requiring full supply-chain transparency without automotive overhead.
Availability
LM2903QD is available at Aetrix Electronics and suitable for server PSU monitoring, factory automation sensor interface, and motor drive overcurrent protection requiring stable component supply across multi-year production cycles.
Supply support for LM2903QD includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with over 90 years of innovation in precision analog ICs and power management solutions.
The LM2903 family was engineered for industrial and automotive voltage comparison tasks-delivering robust performance across wide temperature ranges, high ESD immunity, and rail-to-rail input operation to simplify system-level sensing architectures.
FAQ
What is the maximum supply voltage rating for LM2903QD?
The LM2903QD supports a maximum supply voltage of 36 V, with absolute maximum ratings extending to 38 V for brief transients. This rating is validated per TI's SLCS005AH datasheet Section 5.1, enabling direct use in 24 V industrial systems and 36 V battery-powered equipment without external regulators or clamping diodes.
Does LM2903QD support ground-referenced input signals?
Yes, LM2903QD supports common-mode input voltages down to ground (0 V), as confirmed in Section 5.2 of the datasheet. This allows direct connection of low-side current shunts or battery negative terminals to either input pin without level-shifting circuitry-reducing component count and PCB area in power monitoring designs.
What is the typical propagation delay of LM2903QD under standard test conditions?
The LM2903QD exhibits a typical propagation delay of 1 µs under standard conditions: VS = 5 V, VO_PULLUP = 5 V, CL = 15 pF, RL = 5.1 kΩ, and 5 mV input overdrive. This value is specified in Section 5.7 of the SLCS005AH datasheet and applies across the full −40°C to +125°C operating range.
Can LM2903QD drive a standard 5 V TTL input directly?
Yes, LM2903QD can directly drive a 5 V TTL input via its open-collector output when paired with a 5 V pull-up resistor. With 4 mA sink current, the output voltage remains below 400 mV (Section 5.6), satisfying TTL logic LOW threshold (≤0.8 V). No level-shifter or buffer is needed for interfacing with legacy microcontrollers or FPGAs.
Is LM2903QD pin-compatible with legacy LM2903 variants?
Yes, LM2903QD is pin-compatible with all standard SOIC-8 variants of the LM2903 family-including LM2903, LM2903V, and LM2903AV-as confirmed by identical pin configuration in Figure 4-1 of the datasheet. Mechanical and electrical interoperability is maintained across these parts, enabling drop-in replacement in existing designs.
LM2903QD Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Series:
- -
- Packaging:
- Bulk
- Product Status:
- Active
- Type:
- General Purpose
- Number of Elements:
- 2
- Output Type:
- Open-Collector, Rail-to-Rail
- Voltage - Supply, Single/Dual (±):
- 2V ~ 36V, ±1V ~ 18V
- :
- 7mV @ 30V
- Voltage - Input Offset (Max):
- 0.25µA @ 5V
- Current - Input Bias (Max):
- 20mA
- Current - Output (Typ):
- 2.5mA
- Current - Quiescent (Max):
- -
- CMRR, PSRR (Typ):
- -
- Propagation Delay (Max):
- -
- Hysteresis:
- -40°C ~ 125°C
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- Surface Mount
- :
- 8-SOIC
LM2903QD FAQ
1.How can I place an order for LM2903QD through Aetrix?
Please submit a Request for Quotation (RFQ) for LM2903QD on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for LM2903QD reliable?
The price and inventory of LM2903QD are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM2903QD is usually 5 days.
3.What payment methods are accepted for LM2903QD?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM2903QD transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM2903QD?
LM2903QD orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM2903QD order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for LM2903QD?
For technical support, including LM2903QD datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM2903QD requirements.
6.How does Aetrix verify that LM2903QD is sourced from the original manufacturer or authorized distributors?
All LM2903QD products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that LM2903QD meets industry standards.
7.What is the process for return or replacement of LM2903QD?
All LM2903QD units undergo pre-shipment inspection (PSI). If there is an issue with LM2903QD, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The LM2903QD part is unused and in its original packaging.
Return procedure for LM2903QD:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM2903QD Tags
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