My Inquiry
My Account
Texas Instruments LM4128DMFX-1.8
- Part No.:
- LM4128DMFX-1.8
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- SC-74A, SOT-753
- Datasheet:
-
LM4128DMFX-1.8.pdf
- Description:
- IC VREF SERIES 1% SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:4,519
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM4128DMFX-1.8 from Texas Instruments (formerly National Semiconductor) is a precision micropower series voltage reference in SOT-23-5 package, delivering 1.8 V output with ±1.0% initial accuracy and 100 ppm/°C temperature coefficient over −40°C to +125°C. It features 60 µA quiescent current, 400 mV dropout at 10 mA load, and an enable pin supporting 3 µA shutdown mode-ideal for battery-powered instrumentation and portable data acquisition systems.
For engineers reviewing the LM4128DMFX-1.8 datasheet, LM4128DMFX-1.8 pinout, LM4128DMFX-1.8 application, or LM4128DMFX-1.8 equivalent, key selection considerations include its grade-D accuracy and tempco trade-off, SOT-23-5 footprint constraints, enable-controlled power gating, capacitive-load stability up to 10 µF, and compatibility with low-ESR ceramic bypassing in space-constrained analog signal chains.
Technical Context
The LM4128DMFX-1.8 employs a band-gap–derived series reference architecture with internal enable logic, eliminating external stabilization capacitors while maintaining stability under capacitive loads ≤10 µF. Its low dropout (400 mV @10 mA) and micropower operation (60 µA active, 3 µA shutdown) support direct regulation from single-cell Li-ion or coin-cell sources.
Designed for high-precision analog subsystems, it delivers 170 µVPP (0.1–10 Hz) output noise, 30 ppm/V line regulation, and 25–120 ppm/mA load regulation across its full 0–20 mA output range-enabling use in 12-bit to 14-bit ADC/DAC biasing and sensor excitation where long-term drift (50 ppm/1000 hrs) and thermal hysteresis (75 ppm) are critical.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | 1.8 V nominal, ±1.0% initial accuracy at 25°C - ensures stable reference for low-voltage ADCs without calibration overhead |
| Temperature Coefficient | 100 ppm/°C max (−40°C to +125°C) - supports industrial-grade temperature stability in unregulated environments |
| Quiescent Current | 60 µA typical - enables multi-year operation from CR2032 batteries in portable test equipment |
| Dropout Voltage | 400 mV max at 10 mA load - allows regulation from 2.2 V supply rails, compatible with 2.5 V LDO outputs |
| Enable Function | EN pin enables 3 µA shutdown mode - reduces system standby power in duty-cycled sensor nodes |
| Output Noise | 170 µVPP (0.1–10 Hz) - meets SNR requirements for 12-bit precision data acquisition at low frequencies |
| Load Current | Up to 20 mA - sufficient to drive multiple op-amp bias networks or SAR ADC reference inputs simultaneously |
Pinout & Package
SOT-23-5 package (NS MF05A), 1.6 mm × 2.9 mm footprint, 1.1 mm height - optimized for high-density PCB layouts in handheld instruments and automotive control modules.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | N/C | No-connect pin; must remain floating - prevents unintended parasitic coupling or mechanical stress-induced voltage shift |
| 2 | GND | Analog ground reference - requires low-impedance connection to clean AGND plane to minimize noise injection |
| 3 | EN | Active-high enable input - driven high (>65% VIN) to activate; pulled low (<35% VIN) or grounded for 3 µA shutdown |
| 4 | VIN | Input supply - must exceed VREF + 400 mV (≥2.2 V) and stay ≤5.5 V; accepts low-ESR ceramic input capacitor ≥0.1 µF |
| 5 | VREF | Precision 1.8 V output - stable with 0–10 µF capacitive loads; optional COUT improves transient response but increases turn-on time |
Key Features
| Feature | Design Value |
|---|---|
| Grade-D precision | ±1.0% initial accuracy and 100 ppm/°C tempco - balances cost and performance for non-critical industrial sensing |
| Capacitor-free stability | Stable with no output capacitor and up to 10 µF load - eliminates BOM count and layout sensitivity in compact designs |
| Micropower shutdown | 3 µA IQ in EN = low state - extends battery life in intermittent-measurement applications like environmental loggers |
| Indefinite short-circuit protection | Current-limited to 75 mA - prevents damage during board-level testing or accidental probe shorts |
| Low-noise output | 170 µVPP (0.1–10 Hz) - avoids degrading effective resolution of 12-bit ADCs in precision measurement front-ends |
Applications
| Portable Data Acquisition | Industrial Sensor Transmitters |
|---|---|
Use Scenario: Handheld multimeters and battery-powered DAQ modules acquiring thermocouple or RTD signals. IC Role / Device Role / Timing Role: Primary voltage reference for 12-bit SAR ADCs and analog front-end gain stages. Use Value: 60 µA quiescent current and 3 µA shutdown extend CR2032 battery life beyond 3 years in sleep-wake cycles. |
Use Scenario: 4–20 mA loop-powered transmitters in factory automation monitoring pressure, flow, or level. IC Role / Device Role / Timing Role: Stable 1.8 V reference for DAC output scaling and sensor excitation circuitry. Use Value: 100 ppm/°C tempco ensures <±0.2% full-scale error across −40°C to +85°C ambient operating range. |
| Battery Management Systems | Automotive Diagnostic Tools |
Use Scenario: Cell voltage monitoring in 2–3S Li-ion packs for portable power tools and medical devices. IC Role / Device Role / Timing Role: Reference for high-side current-sense amplifiers and cell-balancing ADCs. Use Value: 400 mV dropout enables direct regulation from 2.2 V auxiliary rails, minimizing heat dissipation in sealed enclosures. |
Use Scenario: OBD-II scan tools and ECU reprogramming adapters requiring reliable analog signal conditioning. IC Role / Device Role / Timing Role: Precision reference for op-amp-based signal isolation and CAN bus interface biasing. Use Value: SOT-23-5 package and −40°C to +125°C operation meet AEC-Q200 stress requirements for under-hood diagnostics hardware. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar voltage reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX6126AUT18 | 1.8 V, ±0.1% initial accuracy, 3 ppm/°C tempco, 65 µA IQ, SOT-23-6 | Higher precision and lower drift - suited for 16-bit+ systems where calibration is impractical | Select MAX6126AUT18 when long-term stability (<15 ppm/1000 hrs) and ultra-low tempco outweigh cost and pin-count constraints. |
| REF3018 | 1.8 V, ±0.2% initial accuracy, 50 ppm/°C tempco, 50 µA IQ, SOT-23-3 | Fewer pins, no enable function, lower quiescent current - simpler integration where shutdown is unnecessary | Choose REF3018 for cost-sensitive, always-on applications like basic sensor signal chains where enable control adds no value. |
Compared with LM4128DMFX-1.8, MAX6126AUT18 offers superior accuracy and thermal stability at higher cost and pin count, while REF3018 simplifies design with lower IQ and no enable logic-but sacrifices programmability and robustness in variable-load conditions.
Availability
LM4128DMFX-1.8 is available at Aetrix Electronics and suitable for portable instrumentation, industrial sensor transmitters, and battery management systems requiring stable component supply with consistent parametric performance across production lots.
Supply support for LM4128DMFX-1.8 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 acquired National Semiconductor in 2011 and maintains its precision analog portfolio, including voltage references, with focus on industrial, automotive, and medical applications.
The LM4128 series was designed as a micropower, capacitor-tolerant series reference for space-constrained, battery-operated systems demanding predictable startup, low dropout, and grade-flexible accuracy.
FAQ
What is the maximum input voltage for LM4128DMFX-1.8?
The LM4128DMFX-1.8 supports a maximum input voltage of 5.5 V. Operation above this level risks permanent damage per Absolute Maximum Ratings. For reliable performance, VIN must also remain ≥2.2 V (VREF + 400 mV) across all load conditions up to 20 mA, ensuring adequate headroom for dropout compliance.
Does LM4128DMFX-1.8 require an input capacitor?
Yes, LM4128DMFX-1.8 requires a minimum 0.1 µF ceramic input capacitor (X5R/X7R) for stable operation. When an output capacitor is used, CIN must be ≥ COUT. Larger input capacitors (4.7–22 µF) reduce output noise and overshoot during startup but do not affect basic functionality.
How does the enable pin function on LM4128DMFX-1.8?
The EN pin on LM4128DMFX-1.8 is active-high: driving it >65% of VIN enables the device; pulling it <35% of VIN places LM4128DMFX-1.8 in 3 µA shutdown mode. The pin has an internal ~2 µA pull-up, so leaving it open defaults to enabled operation-no external resistor needed unless precise control is required.
What is the output noise specification for LM4128DMFX-1.8?
LM4128DMFX-1.8 delivers 170 µVPP (peak-to-peak) output noise over the 0.1 Hz to 10 Hz bandwidth. This low-frequency noise performance directly impacts DC measurement accuracy in precision data acquisition systems using 12-bit ADCs, where it contributes <0.5 LSB error at 1.8 V full scale.
Can LM4128DMFX-1.8 drive a 10 µF capacitive load?
Yes, LM4128DMFX-1.8 is explicitly characterized for stability with capacitive loads up to 10 µF, including low-ESR ceramic types. Adding COUT improves load transient response but increases turn-on time (e.g., 78.8 µs for 10 µF vs. 33.2 µs for 1 µF); no series resistance or isolation is required.
LM4128DMFX-1.8 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- SC-74A, SOT-753
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Reference Type:
- Series
- Output Type:
- Fixed
- Voltage - Output (Min/Fixed):
- 1.8V
- Voltage - Output (Max):
- -
- Current - Output:
- 20 mA
- Tolerance:
- ±1%
- Temperature Coefficient:
- 100ppm/°C
- Noise - 0.1Hz to 10Hz:
- 170µVp-p
- Noise - 10Hz to 10kHz:
- -
- Voltage - Input:
- 2.2V ~ 5.5V
- Current - Supply:
- 100µA
- Current - Cathode:
- -
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
LM4128DMFX-1.8 FAQ
1.How can I place an order for LM4128DMFX-1.8 through Aetrix?
Please submit a Request for Quotation (RFQ) for LM4128DMFX-1.8 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 LM4128DMFX-1.8 reliable?
The price and inventory of LM4128DMFX-1.8 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM4128DMFX-1.8 is usually 5 days.
3.What payment methods are accepted for LM4128DMFX-1.8?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM4128DMFX-1.8 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM4128DMFX-1.8?
LM4128DMFX-1.8 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM4128DMFX-1.8 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 LM4128DMFX-1.8?
For technical support, including LM4128DMFX-1.8 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM4128DMFX-1.8 requirements.
6.How does Aetrix verify that LM4128DMFX-1.8 is sourced from the original manufacturer or authorized distributors?
All LM4128DMFX-1.8 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 LM4128DMFX-1.8 meets industry standards.
7.What is the process for return or replacement of LM4128DMFX-1.8?
All LM4128DMFX-1.8 units undergo pre-shipment inspection (PSI). If there is an issue with LM4128DMFX-1.8, 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 LM4128DMFX-1.8 part is unused and in its original packaging.
Return procedure for LM4128DMFX-1.8:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM4128DMFX-1.8 Tags
-
TL431AIDBZR
Texas Instruments
-
TL431BQDBZR
Texas Instruments
-
AN431AN-ATRG1
Diodes Incorporated
-
LM4040CYM3-2.5-TR
Microchip Technology
-
LM4040CYM3-4.1-TR
Microchip Technology
-
LM4040EIM3-2.5/NOPB
Texas Instruments
-
AZ431LBNTR-G1
Diodes Incorporated
-
LM4040D20IDBZR
Texas Instruments
-
LM4041DIM3-ADJ/NOPB
Texas Instruments
-
LM4040DIM3X-2.5/NOPB
Texas Instruments
-
LM4040DIM3-2.5/NOPB
Texas Instruments
-
AZ431LANTR-G1
Diodes Incorporated
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
