My Inquiry
My Account
Texas Instruments LM4128CMF-1.8
- Part No.:
- LM4128CMF-1.8
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- SC-74A, SOT-753
- Datasheet:
-
LM4128CMF-1.8.pdf
- Description:
- IC VREF SERIES 0.5% SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:2,345
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM4128CMF-1.8 from National Semiconductor is a precision micropower series voltage reference in SOT-23-5 package, delivering 1.8 V output with ±0.5% initial accuracy and 100 ppm/°C temperature coefficient. It features 60 µA quiescent current, 400 mV dropout at 10 mA, and an enable pin supporting 3 µA shutdown mode-ideal for battery-powered instrumentation and portable data acquisition systems.
For engineers reviewing the LM4128CMF-1.8 datasheet, LM4128CMF-1.8 pinout, LM4128CMF-1.8 application, or LM4128CMF-1.8 equivalent, key selection considerations include its C-grade accuracy and tempco performance, low-noise 170 µVPP (0.1–10 Hz), stable operation with up to 10 µF capacitive loads, and compatibility with ceramic input/output bypassing without external stabilization.
Technical Context
The LM4128CMF-1.8 employs a band-gap-derived reference core optimized for micropower operation, eliminating need for external stabilization while maintaining stability with capacitive loads up to 10 µF. Its enable-controlled architecture allows seamless integration into power-gated subsystems.
Designed as a series reference, it avoids idle-load current waste typical of shunt types-enabling efficient operation across 1.8 V to 5.5 V input range with VIN ≥ VREF + 400 mV. The SOT-23-5 package supports compact layout with dedicated EN, GND, VIN, and VREF terminals plus one no-connect pin.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | 1.8 V nominal, ±0.5% initial accuracy at 25°C - ensures ≤9 mV absolute error in precision ADC biasing or DAC reference paths. |
| Temperature Coefficient | 100 ppm/°C max over −40°C to +125°C - contributes ≤21.6 mV drift across full industrial range, suitable for unheated sensor front-ends. |
| Quiescent Current | 60 µA typical - enables multi-year battery life in always-on monitoring nodes drawing <100 µA system current. |
| Dropout Voltage | 400 mV max at 10 mA load - allows operation from 2.2 V supply, compatible with single-cell LiFePO₄ or dual-cell alkaline systems. |
| Shutdown Current | 3 µA max when EN = 0 V - reduces standby power by >95% versus active mode, critical for duty-cycled wireless sensors. |
| Output Noise | 170 µVPP (0.1–10 Hz) - supports 16-bit+ resolution in low-frequency measurement applications without added filtering. |
| Load Regulation | 120 ppm/mA max - maintains ≤0.22 mV change per mA load shift, enabling stable reference for variable-current analog circuits. |
Pinout & Package
SOT-23-5 package (NS MF05A), surface-mount, 1.6 mm × 2.8 mm footprint with 0.95 mm height and 0.95 mm pin pitch. Pin 1 is NC (no connect); pin assignment follows standard top-view orientation.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | N/C | No-connect terminal - must remain floating; not internally bonded and electrically isolated. |
| 2 | GND | Analog ground reference - requires low-impedance connection to system AGND plane to minimize noise coupling. |
| 3 | EN | Active-high enable input - driven high (>65% VIN) to activate reference; pulled up internally (~2 µA), may be tied to VIN if always-on operation is required. |
| 4 | VIN | Input supply - accepts 2.2 V to 5.5 V; must exceed VREF by ≥400 mV under load to maintain regulation. |
| 5 | VREF | Precision 1.8 V output - capable of sourcing up to 20 mA; stable with 0–10 µF capacitive loads including low-ESR ceramics. |
Key Features
| Feature | Design Value |
|---|---|
| Enable-controlled micropower operation | Reduces supply current from 60 µA to 3 µA, enabling firmware-driven power cycling in energy-harvested IoT nodes. |
| Capacitor-free stability design | Eliminates mandatory output capacitor; supports optional COUT up to 10 µF for improved transient response without risk of oscillation. |
| Low thermal hysteresis | 75 ppm over −40°C to +125°C cycling - minimizes calibration drift after thermal excursions in automotive or outdoor equipment. |
| Indefinite short-circuit protection | Limits output current to 75 mA during fault conditions - prevents device damage and maintains system-level safety in test equipment interfaces. |
| Wide operating junction temperature | −40°C to +125°C - qualified for under-hood automotive, industrial motor control, and base station RF module environments. |
Applications
| Portable Data Loggers | Battery-Powered Medical Sensors |
|---|---|
Use Scenario: Continuous 16-bit ADC sampling in handheld ECG or pulse oximeter units powered by coin-cell or Li-ion batteries. IC Role / Device Role / Timing Role: Precision 1.8 V reference for SAR ADC and analog front-end gain stages, enabling accurate biopotential measurement. Use Value: 60 µA quiescent current extends battery life beyond 12 months; ±0.5% accuracy ensures clinical-grade signal fidelity without periodic recalibration. |
Use Scenario: Low-power wearable glucose monitors requiring stable bias for electrochemical transducers and microampere-level current sensing. IC Role / Device Role / Timing Role: Primary voltage reference for transducer excitation and signal conditioning circuitry, operating in intermittent wake-sleep cycles. Use Value: 3 µA shutdown mode cuts baseline power during sleep intervals; 170 µVPP noise preserves resolution in sub-µV biological signal detection. |
| Industrial Process Transmitters | Automotive Cabin Control Modules |
Use Scenario: 4–20 mA loop-powered field instruments measuring pressure, temperature, or flow in factory automation systems. IC Role / Device Role / Timing Role: Stable 1.8 V reference for DAC-based current loop driver and sensor signal conditioning, operating across −40°C to +85°C ambient. Use Value: 100 ppm/°C tempco ensures ≤±1.2 LSB error in 12-bit DAC output over full temperature range; SOT-23-5 eases PCB space constraints in sealed enclosures. |
Use Scenario: HVAC, lighting, and seat control modules in passenger vehicles where EMC robustness and AEC-Q100 compliance are mandatory. IC Role / Device Role / Timing Role: Reference source for microcontroller ADC inputs monitoring potentiometers, thermistors, and PWM-driven actuators. Use Value: Qualified CQ-grade variant available; 125°C junction rating supports placement near heat-generating power stages; EN pin enables coordinated power sequencing with MCU. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar precision voltage reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| REF3018AIDBZR | 1.8 V, ±0.2% initial accuracy, 50 ppm/°C, 50 µA IQ, SOT-23-3 - no enable pin, lower tempco but higher grade cost. | Best for fixed-on applications where shutdown is unnecessary and tighter accuracy justifies premium. | Select REF3018AIDBZR when long-term stability (<20 ppm/1000h) and lower tempco outweigh need for enable control. |
| MAX6029AEUR+T | 1.8 V, ±0.5% initial accuracy, 75 ppm/°C, 35 µA IQ, SOT-23-3 - no enable, lower IQ but limited temp range (−40°C to +85°C). | Suitable for commercial-grade portable devices where extended temperature operation is not required. | Choose MAX6029AEUR+T for cost-sensitive consumer electronics with ambient-limited deployment and no need for automotive/industrial temp range. |
Compared with LM4128CMF-1.8, REF3018AIDBZR offers superior accuracy and tempco but lacks enable functionality and costs more; MAX6029AEUR+T matches C-grade accuracy at lower IQ but sacrifices high-temperature capability-making LM4128CMF-1.8 the optimal balance of enable control, 125°C operation, and industrial-grade stability.
Availability
LM4128CMF-1.8 is available at Aetrix Electronics and suitable for portable medical sensors, industrial process transmitters, battery-powered data loggers, and automotive cabin control modules requiring stable component supply across extended temperature ranges and multi-year production cycles.
Supply support for LM4128CMF-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
National Semiconductor was a U.S.-based analog semiconductor company acquired by Texas Instruments in 2011, renowned for high-precision voltage references, data converters, and power management ICs.
The LM4128 series was designed specifically for space-constrained, battery-operated systems demanding micropower consumption, low dropout, and guaranteed performance across −40°C to +125°C-targeting instrumentation, industrial sensing, and automotive subsystems.
FAQ
What is the maximum load current supported by the LM4128CMF-1.8?
The LM4128CMF-1.8 supports up to 20 mA output current while maintaining regulation and specified accuracy. At 10 mA load, dropout voltage remains ≤400 mV; output voltage deviation due to load changes is bounded by 120 ppm/mA, ensuring predictable behavior in dynamic current-sink applications such as DAC buffers or op-amp bias networks.
Does the LM4128CMF-1.8 require an input capacitor?
Yes-the LM4128CMF-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 startup overshoot and improve PSRR; the device remains stable with low-ESR ceramics and does not require tantalum or electrolytic types.
How does the enable pin function on the LM4128CMF-1.8?
The EN pin on the LM4128CMF-1.8 is active-high with internal ~2 µA pull-up. Driving EN ≥65% of VIN activates the reference; pulling EN ≤35% of VIN places LM4128CMF-1.8 in shutdown mode, reducing supply current to ≤7 µA. EN may be left floating (default enabled) or tied directly to VIN for always-on use-no external pull-up resistor is needed.
What is the thermal hysteresis specification for the LM4128CMF-1.8?
The LM4128CMF-1.8 exhibits 75 ppm thermal hysteresis over −40°C to +125°C cycling, meaning the 1.8 V output shifts by ≤0.135 mV when returning to 25°C after extreme temperature exposure. This low hysteresis supports repeatable calibration in field-deployed equipment subject to repeated thermal cycling, such as outdoor environmental sensors or engine bay modules.
Is the LM4128CMF-1.8 qualified for automotive applications?
The LM4128CMF-1.8 itself is not automotive-qualified; however, its pin-compatible automotive-grade counterpart LM4128CQ1MF1.8 is AEC-Q100 Grade 1 qualified (−40°C to +125°C) and manufactured on an enhanced automotive flow. For non-automotive industrial use, LM4128CMF-1.8 meets full industrial temperature and reliability requirements, including 125°C junction rating and 1000-hour long-term stability testing.
LM4128CMF-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:
- ±0.5%
- 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
LM4128CMF-1.8 FAQ
1.How can I place an order for LM4128CMF-1.8 through Aetrix?
Please submit a Request for Quotation (RFQ) for LM4128CMF-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 LM4128CMF-1.8 reliable?
The price and inventory of LM4128CMF-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 LM4128CMF-1.8 is usually 5 days.
3.What payment methods are accepted for LM4128CMF-1.8?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM4128CMF-1.8 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM4128CMF-1.8?
LM4128CMF-1.8 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM4128CMF-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 LM4128CMF-1.8?
For technical support, including LM4128CMF-1.8 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM4128CMF-1.8 requirements.
6.How does Aetrix verify that LM4128CMF-1.8 is sourced from the original manufacturer or authorized distributors?
All LM4128CMF-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 LM4128CMF-1.8 meets industry standards.
7.What is the process for return or replacement of LM4128CMF-1.8?
All LM4128CMF-1.8 units undergo pre-shipment inspection (PSI). If there is an issue with LM4128CMF-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 LM4128CMF-1.8 part is unused and in its original packaging.
Return procedure for LM4128CMF-1.8:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM4128CMF-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…
