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Analog Devices Inc./Maxim Integrated LM4040AEX3-2.1
- Part No.:
- LM4040AEX3-2.1
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Voltage Reference
- Package:
- SC-70, SOT-323
- Datasheet:
-
LM4040AEX3-2.1.pdf
- Description:
- PRECISION MICROPOWER SHUNT VREF
- Quantity:
- Payment:
- Shipping:
Inventory:2,077
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Product details
Overview
LM4040AEX3-2.1 from Maxim Integrated is a precision 2.048V two-terminal shunt voltage reference in SC70-3 package, featuring 0.1% initial accuracy, ±100ppm/°C temperature coefficient, and guaranteed operation from –40°C to +125°C. It delivers stable reverse-breakdown voltage with 60μA to 15mA shunt current capability and low 28μVRMS wideband noise (10Hz–10kHz), ideal for high-accuracy analog sensing in battery-powered instrumentation.
For engineers reviewing the LM4040AEX3-2.1 datasheet, LM4040AEX3-2.1 pinout, LM4040AEX3-2.1 application, or LM4040AEX3-2.1 equivalent, key selection criteria include its ultra-small SC70 footprint, tight initial tolerance, extended temperature range, and capacitor-free stability-critical for space-constrained, high-reliability industrial and portable designs.
Technical Context
The LM4040AEX3-2.1 uses bandgap-based shunt regulation to maintain a precise 2.048V reverse breakdown voltage across its terminals when biased with 60μA–15mA cathode-to-anode current. Its laser-trimmed internal resistor network ensures 0.1% initial accuracy at +25°C, while thermal design guarantees ≤±100ppm/°C drift over –40°C to +125°C.
No external capacitor is required for stability, and it tolerates any capacitive load without oscillation. The device exhibits low dynamic impedance (≤0.8Ω at 1mA) and minimal voltage change (<1.0mV) across its full operating current range, enabling robust performance in varying load and supply conditions.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | 2.048V nominal; ±2.0mV (±0.1%) initial tolerance at +25°C ensures high-precision ADC/DAC reference accuracy |
| Temperature Coefficient | ±100ppm/°C max over –40°C to +125°C; enables <±1.3mV total drift across full range for stable long-term calibration |
| Operating Current Range | 60μA to 15mA shunt current; supports micropower sensor nodes and higher-current analog front-ends without external biasing complexity |
| Dynamic Impedance | 0.3Ω to 0.8Ω at 1mA; maintains <1mV output variation under fast load transients, critical for precision measurement systems |
| Wideband Noise | 28μVRMS (10Hz–10kHz); minimizes noise contribution in high-resolution data acquisition circuits |
| Long-Term Stability | 120ppm after 1000h; ensures reference integrity over years of field operation in industrial control modules |
Pinout & Package
LM4040AEX3-2.1 is housed in a 3-pin SC70 surface-mount package (1.8mm × 1.8mm), 50% smaller than SOT23 equivalents. Pin 3 is no-connect (N.C.) and must remain unconnected or tied to pin 2.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (+) | Positive terminal (cathode) | Reverse-biased input; connects to regulated voltage rail or source resistor; carries full shunt current |
| 2 (–) | Negative terminal (anode) | Reference ground node; forms return path for shunt current and defines output voltage reference point |
| 3 (N.C.) | No connection | Must be left floating or shorted to pin 2; no internal connection-violating this risks parametric deviation |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-small SC70-3 package | 1.8mm × 1.8mm footprint saves PCB area in wearables, medical sensors, and compact IoT edge nodes |
| 0.1% initial accuracy | Eliminates need for system-level trimming in factory-calibrated instruments and portable test equipment |
| No output capacitor required | Reduces BOM count and layout complexity while ensuring stability with any capacitive load up to 10µF |
| –40°C to +125°C operation | Enables deployment in automotive under-hood modules, industrial motor drives, and outdoor infrastructure |
| Low 28μVRMS noise | Preserves signal integrity in 16-bit+ SAR ADC references and low-noise amplifier bias networks |
Applications
| Portable Medical Sensors | Battery-Powered Data Loggers |
|---|---|
Use Scenario: Continuous glucose monitor (CGM) with integrated analog front-end measuring electrochemical current. IC Role / Device Role / Timing Role: Precision 2.048V shunt reference for 16-bit ADC conversion of microamp-level sensor signals. Use Value: 0.1% initial accuracy and ±100ppm/°C TC ensure <±2mV error over body-temperature range, directly improving diagnostic confidence. | Use Scenario: Remote environmental sensor node logging temperature/humidity with 10-year battery life. IC Role / Device Role / Timing Role: Low-quiescent shunt reference supplying stable bias to op-amps and ADCs during intermittent wake-up cycles. Use Value: 60μA minimum operating current enables sub-100μA system sleep current, extending coin-cell lifetime beyond specification. |
| Industrial Process Transmitters | Automotive Cabin Control Modules |
Use Scenario: 4–20mA loop-powered pressure transmitter operating in harsh factory environments. IC Role / Device Role / Timing Role: Primary voltage reference for DAC-driven current output stage and internal diagnostics circuitry. Use Value: Guaranteed –40°C to +125°C operation and 120ppm long-term stability maintain loop accuracy across 15+ year service life without recalibration. | Use Scenario: HVAC control unit inside vehicle cabin with ambient temperature swings from –40°C to +85°C. IC Role / Device Role / Timing Role: Reference for thermistor interface and microcontroller ADC used in cabin temperature feedback loop. Use Value: SC70-3 size fits constrained dashboard PCB real estate; ±100ppm/°C TC prevents false temperature readings during rapid cabin warm-up/cool-down. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt voltage reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TLVH431ACDBVR | Adjustable 1.24V–18V output; 0.5% initial accuracy; SOT23-3; requires external resistors for 2.048V setting | Less accurate and less stable (±150ppm/°C) than LM4040AEX3-2.1; suitable only where programmability outweighs precision loss | Select only if adjustable output is mandatory and ±5mV reference error is acceptable in final system calibration |
| ADR3420ARJZ-R7 | Fixed 2.048V; 0.1% accuracy; ±30ppm/°C TC; SC70-5; 3.5μA quiescent current; series topology | Lower TC and lower power, but larger package and series architecture demands different biasing and load isolation | Prefer for ultra-low-power or ultra-stable applications where board space allows SC70-5 and series reference topology is feasible |
Compared with TLVH431ACDBVR and ADR3420ARJZ-R7, LM4040AEX3-2.1 offers the optimal balance of fixed 2.048V precision, ultra-small SC70-3 footprint, and proven shunt stability-making it the preferred choice for cost-sensitive, space-constrained industrial and portable systems requiring guaranteed 0.1% accuracy over full temperature range.
Availability
LM4040AEX3-2.1 is available at Aetrix Electronics and suitable for portable medical sensors, battery-powered data loggers, and industrial process transmitters requiring stable component supply with guaranteed long-term availability and RoHS-compliant sourcing.
Supply support for LM4040AEX3-2.1 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
Maxim Integrated is a semiconductor company specializing in analog and mixed-signal ICs for industrial, communications, computing, and consumer applications.
The LM4040 product line delivers precision shunt voltage references optimized for space-constrained, high-accuracy systems-designed to replace discrete zener solutions with superior initial accuracy, temperature stability, and micropower operation.
FAQ
What is the exact output voltage and tolerance of LM4040AEX3-2.1 at +25°C?
The LM4040AEX3-2.1 has a nominal reverse breakdown voltage of 2.048V at +25°C, with a guaranteed initial tolerance of ±2.0mV (±0.1%). This value is laser-trimmed and specified in the Electrical Characteristics table for the A-grade device under standard test conditions (IR = 100μA).
Does LM4040AEX3-2.1 require an external output capacitor for stability?
No, LM4040AEX3-2.1 does not require an external output capacitor. Its internal design ensures stability with any capacitive load, including values up to 10µF. This eliminates BOM cost and layout risk associated with capacitor selection and placement-confirmed in the Applications Information section of the datasheet.
What is the operating temperature range guaranteed for LM4040AEX3-2.1?
LM4040AEX3-2.1 is guaranteed over the extended industrial temperature range of –40°C to +125°C. This is indicated by the "E" suffix in the part number and confirmed in the Ordering Information table, where LM4040AEX3-2.1 is explicitly listed with "–40°C to +125°C" under Temperature Range.
How does the pin configuration of LM4040AEX3-2.1 differ from standard 3-pin voltage references?
LM4040AEX3-2.1 uses a 3-pin SC70 package with pins labeled (+), (–), and N.C. Pin 1 is the cathode (+), Pin 2 is the anode (–), and Pin 3 is no-connect-must remain unconnected or tied to Pin 2. Unlike series references, it has no VOUT or REF pin; output voltage appears directly across Pins 1 and 2.
Can LM4040AEX3-2.1 be used in place of LM4040AIM3-2.1?
Yes, LM4040AEX3-2.1 can replace LM4040AIM3-2.1 in most designs, as both share identical electrical specs (2.048V, 0.1%, ±100ppm/°C). However, LM4040AEX3-2.1 uses SC70-3 (1.8mm × 1.8mm), while LM4040AIM3-2.1 uses SOT23-3 (2.9mm × 1.6mm). PCB layout must be updated to accommodate the smaller footprint and different land pattern.
LM4040AEX3-2.1 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Package/Case:
- SC-70, SOT-323
- Series:
- -
- Packaging:
- Bulk
- Product Status:
- Active
- Reference Type:
- Shunt
- Output Type:
- Fixed
- Voltage - Output (Min/Fixed):
- 2.048V
- Voltage - Output (Max):
- -
- Current - Output:
- 15 mA
- Tolerance:
- ±0.1%
- Temperature Coefficient:
- 100ppm/°C
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- 28µVrms
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 65 µA
- Operating Temperature:
- -40°C ~ 125°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SC-70-3
LM4040AEX3-2.1 FAQ
1.How can I place an order for LM4040AEX3-2.1 through Aetrix?
Please submit a Request for Quotation (RFQ) for LM4040AEX3-2.1 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 LM4040AEX3-2.1 reliable?
The price and inventory of LM4040AEX3-2.1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM4040AEX3-2.1 is usually 5 days.
3.What payment methods are accepted for LM4040AEX3-2.1?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM4040AEX3-2.1 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM4040AEX3-2.1?
LM4040AEX3-2.1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM4040AEX3-2.1 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 LM4040AEX3-2.1?
For technical support, including LM4040AEX3-2.1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM4040AEX3-2.1 requirements.
6.How does Aetrix verify that LM4040AEX3-2.1 is sourced from the original manufacturer or authorized distributors?
All LM4040AEX3-2.1 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 LM4040AEX3-2.1 meets industry standards.
7.What is the process for return or replacement of LM4040AEX3-2.1?
All LM4040AEX3-2.1 units undergo pre-shipment inspection (PSI). If there is an issue with LM4040AEX3-2.1, 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 LM4040AEX3-2.1 part is unused and in its original packaging.
Return procedure for LM4040AEX3-2.1:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM4040AEX3-2.1 Tags
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