My Inquiry
My Account
STMicroelectronics LMX321ICT
.jpg)
- Part No.:
- LMX321ICT
- Manufacturer:
- STMicroelectronics
- Category:
- Instrumentation, Op Amps, Buffer Amps
- Package:
- 5-TSSOP, SC-70-5, SOT-353
- Datasheet:
-
LMX321ICT.pdf
- Description:
- IC OPAMP GP 1 CIRCUIT SC70-5
- Quantity:
- Payment:
- Shipping:
Inventory:8,153
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LMX321ICT from STMicroelectronics is a single-channel, rail-to-rail output operational amplifier optimized for low-voltage, low-power applications. It operates from 2.3 V to 5.5 V, draws only 120 µA supply current per channel at 2.7 V, delivers 1.3 MHz gain bandwidth, and supports operation across –40 °C to +125 °C. It is used in battery-powered medical instrumentation signal conditioning stages where rail-to-rail swing and minimal quiescent power are critical.
For engineers reviewing the LMX321ICT datasheet, LMX321ICT pinout, LMX321ICT application, or LMX321ICT equivalent, key selection considerations include its 120 µA supply current at 2.7 V, rail-to-rail output swing within 180 mV of rails (RL = 10 kΩ), input common-mode range extending to ground, 1.3 MHz GBP, and guaranteed performance over industrial temperature range.
Technical Context
The LMX321ICT employs a CMOS input stage enabling rail-to-rail input common-mode range (VCC− − 0.2 V to VCC+ − 1 V) and eliminates phase reversal. Its output stage is designed for true rail-to-rail swing with 10–180 mV headroom depending on load and temperature.
It achieves unity-gain stability driving capacitive loads up to 200 pF, features 60° phase margin and 10 dB gain margin at 5 V, and maintains 0.6–0.7 V/µs slew rate across 2.7–5 V supply. Input offset voltage is specified at 4–6 mV (–40 °C to +125 °C), with drift ≤1 µV/°C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage Range | 2.3 V to 5.5 V - enables direct use with single-cell Li-ion, NiMH, or 3.3 V/5 V logic rails. |
| Quiescent Current | 120 µA per channel at 2.7 V - allows >1-year battery life in always-on portable sensors. |
| Gain Bandwidth Product | 1.3 MHz - supports stable closed-loop gain ≥10 at 100 kHz for active filtering. |
| Rail-to-Rail Output Swing | Within 10–180 mV of VCC+/VCC− (RL = 10 kΩ) - maximizes dynamic range in low-voltage ADC driver stages. |
| Input Common-Mode Range | VCC− − 0.2 V to VCC+ − 1 V - accepts signals down to ground without clipping in single-supply configurations. |
| Operating Temperature | –40 °C to +125 °C - qualified for under-hood automotive and industrial control environments. |
| Input Offset Voltage | 4–6 mV (–40 °C to +125 °C) - sufficient for 12-bit precision in sensor front-ends with calibration. |
Pinout & Package
LMX321ICT is housed in a SC70-5 (SOT323-5) package - a 1.2 mm × 2.0 mm, 0.65 mm pitch surface-mount package with exposed pad option for thermal enhancement.
| Pin | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Inverting Input (IN−) | Differential input node; high-impedance CMOS input accepting signals from VCC− − 0.2 V to VCC+ − 1 V. |
| 2 | Non-inverting Input (IN+) | Differential input node; same common-mode range as IN−; used for reference or signal injection. |
| 3 | Output (OUT) | Rail-to-rail output capable of sourcing/sinking ≥15 mA; drives 10 kΩ loads to within 10–180 mV of rails. |
| 4 | VCC− (Ground) | Negative supply terminal; must be connected to system ground or negative rail; referenced for all input/output voltages. |
| 5 | VCC+ | Positive supply terminal; accepts 2.3–5.5 V; requires local 10 nF decoupling per layout guidelines. |
Key Features
| Feature | Design Value |
|---|---|
| No phase reversal | Guaranteed over full input common-mode range - prevents latch-up or erratic behavior when inputs exceed rails. |
| No crossover distortion | CMOS input + Class AB output architecture eliminates dead-zone distortion near zero-crossing in AC-coupled paths. |
| Unity-gain stable | Stable with capacitive loads ≤200 pF - simplifies design of ADC drivers and active filters without external compensation. |
| Extended temperature operation | Specified from –40 °C to +125 °C - eliminates derating calculations for harsh-environment deployments. |
| Tiny SC70-5 footprint | 1.2 mm × 2.0 mm area - saves PCB space in wearables, implantables, and multi-channel sensor modules. |
Applications
| Portable ECG Front-End | Battery-Voltage Monitor |
|---|---|
Use Scenario: Amplifying microvolt-level biopotential signals from dry electrodes in a handheld ECG device powered by a 3.0 V coin cell. IC Role / Device Role / Timing Role: Single-supply, rail-to-rail op-amp configured as non-inverting amplifier (G = 100) with DC-coupled input to preserve baseline integrity. Use Value: 120 µA quiescent current extends battery life beyond 18 months; rail-to-rail output ensures full utilization of 12-bit ADC input range. |
Use Scenario: Monitoring lithium coin cell voltage (2.0–3.3 V) in a Bluetooth LE beacon, triggering low-battery alert at 2.4 V. IC Role / Device Role / Timing Role: Precision comparator-like function using op-amp in open-loop configuration with resistive divider feedback. Use Value: Input common-mode range including ground enables direct sensing of battery anode vs. system ground; 4–6 mV Vos allows ±15 mV threshold accuracy after calibration. |
| Wearable Motion Sensor Signal Chain | Industrial Temperature Transmitter |
Use Scenario: Conditioning analog outputs from MEMS accelerometers and gyroscopes in a compact fitness tracker with tight power budget. IC Role / Device Role / Timing Role: Low-noise, low-drift buffer and level-shifter between sensor and SAR ADC, operating from 2.7 V supply. Use Value: 0.6 V/µs slew rate supports 100 kHz sensor bandwidth; 31 nV/√Hz input noise preserves SNR in sub-1 g vibration detection. |
Use Scenario: Amplifying and offsetting RTD or thermistor bridge outputs in a DIN-rail mounted temperature transmitter rated for –40 °C to +85 °C ambient. IC Role / Device Role / Timing Role: Instrumentation-grade signal conditioner in 4–20 mA loop transmitter, powered from 24 V via LDO. Use Value: Guaranteed operation to +125 °C junction temperature enables reliable performance inside sealed enclosures; 70–75 dB CMRR rejects common-mode noise from motor drives. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar general-purpose, low-voltage op-amp applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TSV851ILT | Lower input offset (1.5 mV typ), higher GBP (1.5 MHz), but 150 µA IQ - 25% higher quiescent current than LMX321ICT. | Better DC precision required; acceptable if 30 µA extra current budget exists. | Select TSV851ILT when Vos < 2 mV is mandatory and supply current is secondary. |
| LMV321IDBVR | Same 1.3 MHz GBP and rail-to-rail output, but wider supply range (2.7–5.5 V), higher IQ (160 µA), and no extended temp rating (–40 °C to +125 °C not guaranteed). | Standard commercial-temp designs where cost is prioritized over industrial qualification. | Select LMV321IDBVR for cost-sensitive consumer applications with standard temperature requirements. |
Compared with TSV851ILT and LMV321IDBVR, LMX321ICT uniquely balances ultra-low 120 µA supply current, full industrial temperature qualification, and SC70-5 footprint - making it optimal for space-constrained, battery-powered systems requiring long-term reliability.
Availability
LMX321ICT is available at Aetrix Electronics and suitable for portable medical devices, battery voltage monitoring circuits, wearable sensor signal chains, and industrial temperature transmitters requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for LMX321ICT 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
STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.
The LMX3xx series was developed specifically for ultra-low-power, single-supply signal conditioning in space- and energy-constrained applications - emphasizing rail-to-rail operation, wide temperature resilience, and miniature packaging.
FAQ
Is LMX321ICT unity-gain stable with capacitive loads?
Yes. The LMX321ICT is explicitly characterized and guaranteed unity-gain stable with capacitive loads up to 200 pF, as confirmed in Figures 10–11 of the datasheet. This eliminates need for external compensation in ADC driver or filter applications, provided PCB layout follows recommended 10 nF local decoupling at VCC+.
What is the maximum output current capability of LMX321ICT?
At VCC = 2.7 V, LMX321ICT can source up to 21 mA and sink up to 26 mA (typical); at VCC = 5 V, it sources up to 70 mA and sinks up to 43 mA (typical), as specified in Tables 4 and 5. Output voltage swing degrades above ~15 mA into 10 kΩ due to internal resistance - verify load conditions against Figure 5.
Does LMX321ICT support true rail-to-rail input?
No - it supports rail-to-rail *output*, and its input common-mode range extends from VCC− − 0.2 V to VCC+ − 1 V, which includes ground but does not reach the positive rail. This allows single-supply operation with inputs near ground, but not full rail-to-rail input swing.
Can LMX321ICT replace LMV321 in existing designs?
Functionally yes in most cases - both are single, rail-to-rail output op-amps with 1.3 MHz GBP and SC70-5 packaging. However, LMX321ICT offers guaranteed –40 °C to +125 °C operation and 120 µA IQ vs. LMV321's 160 µA, making it superior for industrial/battery applications - verify layout compatibility and requalification per IEC 60601 or AEC-Q200 if applicable.
LMX321ICT Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- 5-TSSOP, SC-70-5, SOT-353
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Amplifier Type:
- General Purpose
- Number of Circuits:
- 1
- Output Type:
- Rail-to-Rail
- Slew Rate:
- 0.7V/µs
- Gain Bandwidth Product:
- 1.3 MHz
- -3db Bandwidth:
- -
- Current - Input Bias:
- 27 nA
- Voltage - Input Offset:
- 4 mV
- Current - Supply:
- 130µA
- Current - Output / Channel:
- 70 mA
- Voltage - Supply Span (Min):
- 2.3 V
- Voltage - Supply Span (Max):
- 5.5 V
- Operating Temperature:
- -40°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SC-70-5
LMX321ICT FAQ
1.How can I place an order for LMX321ICT through Aetrix?
Please submit a Request for Quotation (RFQ) for LMX321ICT 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 LMX321ICT reliable?
The price and inventory of LMX321ICT are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LMX321ICT is usually 5 days.
3.What payment methods are accepted for LMX321ICT?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LMX321ICT transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LMX321ICT?
LMX321ICT orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LMX321ICT 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 LMX321ICT?
For technical support, including LMX321ICT datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LMX321ICT requirements.
6.How does Aetrix verify that LMX321ICT is sourced from the original manufacturer or authorized distributors?
All LMX321ICT 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 LMX321ICT meets industry standards.
7.What is the process for return or replacement of LMX321ICT?
All LMX321ICT units undergo pre-shipment inspection (PSI). If there is an issue with LMX321ICT, 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 LMX321ICT part is unused and in its original packaging.
Return procedure for LMX321ICT:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LMX321ICT 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
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
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…
