My Inquiry
My Account
Texas Instruments LF444CMX
- Part No.:
- LF444CMX
- Manufacturer:
- Texas Instruments
- Category:
- Instrumentation, Op Amps, Buffer Amps
- Package:
- 14-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
LF444CMX.pdf
- Description:
- IC OPAMP JFET 4 CIRCUIT 14SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:4,559
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LF444CMX from Texas Instruments is a quad low-power JFET-input operational amplifier designed for precision analog signal conditioning in battery-powered and space-constrained systems. It delivers 1 MHz gain-bandwidth, 1 V/μs slew rate, 50 kV/V minimum open-loop gain, and ultra-low 50 pA (max) input bias current at ±15 V supply - enabling high-impedance sensor interfacing in pH meters, medical instrumentation, and portable data acquisition.
For engineers reviewing the LF444CMX datasheet, LF444CMX pinout, LF444CMX application, or LF444CMX equivalent, key selection considerations include its SOIC-14 package, commercial temperature range (0°C to +70°C), JFET-input noise performance (35 nV/√Hz), and pin compatibility with LM148 for low-power drop-in upgrades.
Technical Context
The LF444CMX integrates four independent JFET-input op-amp channels on a single die, each biased for stable operation down to ±3.0 V supplies. Its BI-FET™ architecture eliminates input clamping diodes, allowing differential input voltages up to ±30 V without increased input current - critical for high-voltage sensor front-ends.
Each amplifier features matched high-impedance inputs (10¹² Ω), rail-to-rail common-mode input range (±11 V at ±15 V supply), and output swing to ±12 V into 10 kΩ - supporting wide dynamic range in single-supply or split-supply configurations without external level-shifting.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Current | 0.6–1.0 mA total (200 μA per amplifier max) - enables 4-channel amplification in sub-1 mA systems. |
| Input Bias Current | 10–100 pA (max at 25°C) - preserves signal integrity in >100 MΩ source impedance circuits like pH electrodes. |
| Gain-Bandwidth Product | 1 MHz - supports stable unity-gain buffering and closed-loop gains up to 100 at 10 kHz. |
| Slew Rate | 1 V/μs - sufficient for 10 kHz full-scale sine wave output at ±10 V swing without distortion. |
| Input Noise Voltage | 35 nV/√Hz at 1 kHz - low-noise performance essential for microvolt-level biomedical signal amplification. |
| Common-Mode Rejection | 70–95 dB - maintains accuracy in noisy industrial environments with ground potential differences. |
| Output Voltage Swing | ±12 V into 10 kΩ - delivers usable dynamic range near supply rails for efficient power utilization. |
Pinout & Package
LF444CMX is housed in a 14-pin SOIC (D) package (JEDEC MS-012, variation AB), 8.75 mm × 4.0 mm footprint, 1.75 mm max height, RoHS-compliant matte tin (Sn) lead finish, MSL Level-1 (260°C peak reflow).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Amplifier 1 Output | High-impedance voltage source driving external load or feedback network. |
| 2 | Amplifier 1 Inverting Input | High-Z node accepting feedback resistor; sensitive to stray capacitance and layout parasitics. |
| 3 | Amplifier 1 Non-Inverting Input | High-Z sensor interface point; requires guard trace if connected to >10 MΩ sources. |
| 4 | Negative Supply (V−) | Reference for all four amplifiers; must be decoupled locally with 0.1 μF ceramic capacitor. |
| 5 | Amplifier 2 Non-Inverting Input | Independent high-Z input for second channel; electrically isolated from other inputs. |
| 6 | Amplifier 2 Inverting Input | Feedback node for second amplifier; shares no internal connection with Pin 2 or Pin 12. |
| 7 | Amplifier 2 Output | Second independent output; capable of sourcing/sinking ±20 mA short-circuit current. |
| 8 | Amplifier 3 Output | Third output channel; identical AC/DC specs to Pins 1 and 7; no cross-talk above −120 dB. |
| 9 | Amplifier 3 Inverting Input | Third inverting input; matches Pin 2 and Pin 6 in offset voltage drift and noise density. |
| 10 | Amplifier 3 Non-Inverting Input | Third high-Z input; suitable for reference voltage buffering or multi-stage filtering. |
| 11 | Positive Supply (V+) | Power rail for all four amplifiers; requires dedicated 0.1 μF + 10 μF parallel decoupling. |
| 12 | Amplifier 4 Inverting Input | Fourth feedback node; fully independent; no shared bias current path with other channels. |
| 13 | Amplifier 4 Non-Inverting Input | Fourth sensor interface; maintains 10¹² Ω input resistance across full temperature range. |
| 14 | Amplifier 4 Output | Final output channel; supports same load drive and settling time as other outputs. |
Key Features
| Feature | Design Value |
|---|---|
| JFET input stage | Enables 10¹² Ω input impedance and 50 pA max input bias current - critical for electrochemical sensor interfaces. |
| Quad configuration in SOIC-14 | Reduces board area by 75% vs. four discrete op-amps; eliminates inter-channel layout mismatch in filter banks. |
| LM148 pin compatibility | Allows direct replacement in existing designs without PCB revision - cutting supply current by 75% immediately. |
| Low 35 nV/√Hz input noise | Preserves SNR in microvolt-level signals from thermocouples or piezoelectric transducers. |
| ±30 V differential input rating | Eliminates need for external input clamping in high-voltage industrial monitoring applications. |
Applications
| pH Electrode Signal Conditioning | Medical ECG Front-End Amplification |
|---|---|
Use Scenario: Amplifying high-impedance (≥1 GΩ), low-current (pA-level) output from glass pH electrodes in portable analyzers. IC Role / Device Role / Timing Role: First-stage buffer and programmable gain amplifier with ultra-low input bias current to prevent electrode polarization. Use Value: Enables accurate pH measurement stability over hours without drift, leveraging 50 pA max input bias current and 10¹² Ω input resistance. |
Use Scenario: Conditioning weak biopotential signals (0.5–5 mV) from dry-electrode ECG sensors in wearable monitors. IC Role / Device Role / Timing Role: Low-noise, low-power instrumentation amplifier input stage rejecting 50/60 Hz interference while preserving ST-segment fidelity. Use Value: Achieves diagnostic-grade signal integrity using 35 nV/√Hz noise floor and 70+ dB CMRR at 60 Hz - extending battery life via 1 mA total supply current. |
| Portable Data Logger Sensor Hub | Industrial RTD Signal Conditioning |
Use Scenario: Multiplexing and amplifying outputs from multiple analog sensors (thermistor, humidity, gas) in battery-operated environmental loggers. IC Role / Device Role / Timing Role: Quad-channel signal conditioner providing simultaneous gain, filtering, and level-shifting before ADC sampling. Use Value: Reduces component count by 4× versus single op-amps; maintains channel-to-channel matching for calibrated multi-sensor correlation. |
Use Scenario: Linearizing and amplifying low-level resistance changes (≤100 Ω) from 3-wire Pt100 RTDs in HVAC control panels. IC Role / Device Role / Timing Role: Precision current-source excitation amplifier and differential receiver in constant-current bridge configuration. Use Value: Delivers 0.1°C temperature resolution using <100 pA input bias current to avoid self-heating errors in high-resistance RTD leads. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar quad JFET-input op-amp applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TLC27L4CDR | Lower supply current (125 μA/amp), but reduced GBW (0.85 MHz) and higher input offset (10 mV max). | Better for ultra-low-power (<500 μA total) systems where bandwidth <100 kHz suffices. | Select TLC27L4CDR only when supply current is primary constraint and 1 MHz bandwidth is not required. |
| TL074CDR | Higher slew rate (13 V/μs) and GBW (3 MHz), but 2× higher supply current (1.4 mA total) and 200 pA input bias current. | Suitable for audio or higher-speed signal paths where noise is secondary to speed. | Choose TL074CDR when bandwidth >1 MHz and slew rate >1 V/μs are mandatory, accepting higher power draw. |
Compared with TLC27L4CDR and TL074CDR, the LF444CMX uniquely balances 1 MHz bandwidth, 50 pA input bias, and 1 mA total supply current - making it optimal for precision, low-power, multi-channel analog sensing where all three parameters are simultaneously constrained.
Availability
LF444CMX is available at Aetrix Electronics and suitable for pH meter design, portable ECG monitoring, environmental data logging, and industrial RTD signal conditioning requiring stable component supply across long production cycles.
Supply support for LF444CMX 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, embedded processing, and connectivity technologies, with decades of heritage in precision op-amp design and manufacturing.
The LF444CMX belongs to TI's legacy BI-FET™ op-amp family, engineered specifically for low-power, high-input-impedance analog signal conditioning in portable and industrial instrumentation.
FAQ
What is the operating temperature range for the LF444CMX?
The LF444CMX is rated for commercial temperature operation from 0°C to +70°C. This range is confirmed in TI's official packaging addendum and electrical characteristics tables, where all DC and AC parameters are specified over this interval. The "C" in the part number denotes commercial grade, and the SOIC (D) package variant LF444CMX does not support extended or military temperature ranges. Operation outside 0°C–70°C may result in unguaranteed performance or reliability degradation.
Is the LF444CMX pin-compatible with the LM148?
Yes, the LF444CMX is explicitly pin-compatible with the LM148, as stated in TI's datasheet: "The LF444 is pin compatible with the LM148 allowing an immediate 4 times reduction in power drain." Both devices use the same 14-pin SOIC (D) and PDIP (N) footprints, with identical pin functions - including shared V+, V−, and channel I/O assignments. This allows direct substitution without PCB modification, provided the lower supply current and improved DC specs of the LF444CMX are acceptable in the target circuit.
What is the maximum differential input voltage the LF444CMX can withstand?
The LF444CMX supports a maximum differential input voltage of ±30 V, as specified in the Absolute Maximum Ratings table under "Differential Input Voltage" for the LF444 grade. This rating is independent of supply voltage and stems from the robust JFET input structure, which eliminates the need for input clamping diodes. Exceeding ±30 V risks gate oxide damage and permanent parametric shift - especially under sustained overvoltage conditions.
Does the LF444CMX require external input protection diodes?
No, the LF444CMX does not require external input protection diodes due to its JFET input architecture. As noted in TI's APPLICATION HINTS section: "These JFETs have large reverse breakdown voltages from gate to source and drain eliminating the need for clamps across the inputs." The device inherently tolerates large differential inputs (±30 V) and common-mode excursions within its specified limits - though care must still be taken to avoid exceeding negative common-mode voltage thresholds to prevent output phase reversal.
What is the typical input noise current of the LF444CMX?
The LF444CMX has a typical input noise current of 0.01 pA/√Hz at 1 kHz, as published in the AC Electrical Characteristics table. This ultra-low value results directly from the JFET input stage's minimal gate leakage and is critical for maintaining signal integrity when amplifying currents from high-impedance sources such as photodiodes or piezoelectric sensors. The datasheet confirms this spec applies across the full commercial temperature range and is measured under standard conditions (VS = ±15 V, TA = 25°C).
LF444CMX Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 14-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Amplifier Type:
- J-FET
- Number of Circuits:
- 4
- Output Type:
- -
- Slew Rate:
- 1V/µs
- Gain Bandwidth Product:
- 1 MHz
- -3db Bandwidth:
- -
- Current - Input Bias:
- 10 pA
- Voltage - Input Offset:
- 3 mV
- Current - Supply:
- 600µA (x4 Channels)
- Current - Output / Channel:
- 14 mA
- Voltage - Supply Span (Min):
- 36 V
- Voltage - Supply Span (Max):
- 36 V
- Operating Temperature:
- 0°C ~ 70°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 14-SOIC
LF444CMX FAQ
1.How can I place an order for LF444CMX through Aetrix?
Please submit a Request for Quotation (RFQ) for LF444CMX 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 LF444CMX reliable?
The price and inventory of LF444CMX are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LF444CMX is usually 5 days.
3.What payment methods are accepted for LF444CMX?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LF444CMX transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LF444CMX?
LF444CMX orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LF444CMX 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 LF444CMX?
For technical support, including LF444CMX datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LF444CMX requirements.
6.How does Aetrix verify that LF444CMX is sourced from the original manufacturer or authorized distributors?
All LF444CMX 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 LF444CMX meets industry standards.
7.What is the process for return or replacement of LF444CMX?
All LF444CMX units undergo pre-shipment inspection (PSI). If there is an issue with LF444CMX, 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 LF444CMX part is unused and in its original packaging.
Return procedure for LF444CMX:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LF444CMX Tags
-
LM358DT
STMicroelectronics
-
LM358DR
Texas Instruments
-
LM2904DR
Texas Instruments
-
LM358ADR
Texas Instruments
-
LM2904DGKR
Texas Instruments
-
LM324DR
Texas Instruments
-
MCP6006T-E/OT
Microchip Technology
-
MCP6006UT-E/OT
Microchip Technology
-
LM324PWR
Texas Instruments
-
LM2902PWR
Texas Instruments
-
LM2902DR
Texas Instruments
-
LM358P
Texas Instruments
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…
