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Texas Instruments OPA349NA/3KG4
- Part No.:
- OPA349NA/3KG4
- Manufacturer:
- Texas Instruments
- Category:
- Instrumentation, Op Amps, Buffer Amps
- Package:
- SC-74A, SOT-753
- Datasheet:
-
OPA349NA/3KG4.pdf
- Description:
- IC OPAMP GP 1 CIRCUIT SOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:4,134
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Product details
Overview
OPA349NA/3KG4 from Texas Instruments is a single-channel, ultra-low-power, rail-to-rail input/output CMOS operational amplifier optimized for battery-powered systems. It delivers 70kHz gain-bandwidth, 1µA quiescent current, 90dB open-loop gain, and operates from 1.8V to 5.5V supply - enabling precision signal conditioning in portable smoke detectors and solar-powered remote sensors.
For engineers reviewing the OPA349NA/3KG4 datasheet, OPA349NA/3KG4 pinout, OPA349NA/3KG4 application, or OPA349NA/3KG4 equivalent, key selection criteria include micropower operation (<2µA max IQ), rail-to-rail I/O swing (±350mV from rails), low input bias current (≤10pA), and SOT23-5 package compatibility with high-density PCB layouts.
Technical Context
The OPA349NA/3KG4 employs a complementary differential input stage enabling rail-to-rail common-mode input range extending 200mV beyond both supply rails. Its unity-gain stable architecture eliminates need for external compensation, supporting direct use in buffer and gain-of-one configurations without oscillation risk.
Output stage delivers ±8mA drive into 10kΩ loads while maintaining 350mV rail clearance at 5.5V supply. Input voltage noise density is 300nV/√Hz at 1kHz, and open-loop gain remains ≥74dB over temperature (0°C to +70°C specified range).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage | 1.8V to 5.5V - supports operation down to single-cell Li-ion or two-cell alkaline battery voltage without performance degradation. |
| Quiescent Current | 1µA typical - enables multi-year battery life in always-on remote sensor nodes drawing <10µA system current. |
| Gain-Bandwidth Product | 70kHz - sufficient for anti-aliasing filters, sensor amplification, and slow-control loops in power-supply monitoring circuits. |
| Input Bias Current | ≤10pA max - permits use of >10MΩ feedback/source resistors without significant offset error in high-impedance pH or gas sensor interfaces. |
| Input Common-Mode Range | (V–) – 0.2V to (V+) + 0.2V - allows direct sensing of signals referenced to ground or V+ in single-supply systems. |
| Output Swing | Within 350mV of rails at 10kΩ load - preserves dynamic range when driving ADC reference inputs or low-voltage comparators. |
| Open-Loop Gain | 90dB typical - ensures ≤1mV output error for 1V input with unity-gain configuration, critical for precision DC-coupled signal chains. |
Pinout & Package
SOT23-5 surface-mount package (DBV), 1.6mm × 2.9mm footprint, 1.1mm max height, moisture sensitivity level 2, lead-free NiPdAu finish.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - V+ | Positive supply rail | Accepts 1.8V–5.5V; requires local 0.01µF ceramic bypass capacitor to minimize PSRR degradation. |
| 2 - –In | Inverting input | Differential pair node; input bias current ≤10pA enables high-Z sensor interfacing without guard traces. |
| 3 - Out | Amplifier output | Capable of ±8mA sink/source; swings to within 350mV of V– or V+ under 10kΩ load. |
| 4 - V– | Negative supply rail / Ground | Reference for single-supply operation; output may oscillate if driven into this rail with capacitive loads. |
| 5 - +In | Non-inverting input | Complementary input pair node; common-mode range extends 200mV beyond V– and V+, enabling true rail-to-rail sensing. |
Key Features
| Feature | Design Value |
|---|---|
| Rail-to-rail input and output | Enables full utilization of 1.8V–5.5V supply range in single-supply systems, maximizing ADC input dynamic range without level-shifting circuitry. |
| Unity-gain stable | Eliminates need for external compensation components in buffer, follower, or gain-of-one configurations - reducing BOM count and board area. |
| 1µA quiescent current | Supports >10-year battery life in maintenance-free IoT sensor nodes operating continuously at 1–5µA system-level current. |
| Low input bias current (10pA max) | Permits direct connection to high-impedance sources (e.g., electrochemical sensors, photodiodes) without significant input error or drift. |
| Wide supply range (1.8V–5.5V) | Ensures consistent performance across battery discharge curves - no brown-out reset or gain shift as voltage drops from 4.2V to 2.8V. |
Applications
| Battery-Powered Smoke Detectors | Solar-Powered Remote Environmental Sensors |
|---|---|
Use Scenario: Amplifying weak ionization chamber current (pA–nA) in low-power smoke alarm ASICs with 10-year coin-cell battery life. IC Role / Device Role / Timing Role: Precision transimpedance amplifier front-end with rail-to-rail input enabling detection of sub-100mV chamber voltage shifts. Use Value: 1µA IQ minimizes standby current; 10pA IB prevents signal loss across megaohm feedback resistors used for pA-level sensitivity. | Use Scenario: Signal conditioning for thermistor, humidity, and CO₂ sensors in off-grid agricultural monitoring nodes powered by 2.5V solar cells. IC Role / Device Role / Timing Role: Low-drift, rail-to-rail buffer driving 12-bit SAR ADC inputs while operating from unregulated 1.8V–3.3V supply. Use Value: 70kHz GBW supports 100Hz sensor bandwidth; 350mV rail swing preserves 2.8V full-scale ADC range at 3.3V supply. |
| Portable Medical Pulse Oximeters | PCMCIA Card Analog Front-Ends |
Use Scenario: Amplifying red/infrared photodiode currents in battery-operated fingertip pulse oximeters requiring continuous 24/7 operation. IC Role / Device Role / Timing Role: Dual-stage amplifier (first stage transimpedance, second stage gain/filter) with micropower biasing. Use Value: Rail-to-rail I/O allows direct interface to 1.8V ADC; 90dB AOL ensures <0.1% gain error in DC-coupled LED driver feedback paths. | Use Scenario: Signal conditioning for analog I/O on legacy PCMCIA cards used in industrial handheld test equipment. IC Role / Device Role / Timing Role: Input protection and level-shifting buffer between card-edge connector and internal 3.3V logic. Use Value: SOT23-5 footprint fits tight 5mm card edge spacing; 5.5V absolute max rating protects against hot-plug transients up to 6V. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar micropower rail-to-rail op amp applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TLV2401IDBVR | Same 1µA IQ and rail-to-rail I/O, but 5.5kHz GBW (vs 70kHz); 10x lower bandwidth limits AC response. | Not suitable for >1kHz sensor filtering or fast-settling ADC drivers; better for pure DC biasing. | Select TLV2401IDBVR only when bandwidth demand is <10kHz and cost is primary constraint. |
| OPA347UA/2K5 | 20µA IQ (20× higher), 350kHz GBW, same SOT23-5 package; higher speed but 20× quiescent current penalty. | Appropriate for higher-speed sensor interfaces where battery life is secondary to signal fidelity. | Choose OPA347UA/2K5 when system requires >50kHz closed-loop bandwidth and can tolerate 20µA per channel. |
Compared with TLV2401IDBVR, OPA349NA/3KG4 provides 12.7× higher bandwidth for the same 1µA IQ; versus OPA347UA/2K5, it reduces quiescent current by 95% at the cost of bandwidth - making it optimal for ultra-long-life, low-frequency sensing.
Availability
OPA349NA/3KG4 is available at Aetrix Electronics and suitable for battery packs, portable medical devices, and solar-powered environmental monitoring systems requiring stable component supply with guaranteed long-term traceability.
Supply support for OPA349NA/3KG4 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 and embedded processing technologies, with decades of expertise in precision op amps and low-power signal chain solutions.
The OPA349 series belongs to TI's precision micropower op amp product line, designed specifically for energy-constrained applications where extended battery life, rail-to-rail operation, and minimal design overhead are critical.
FAQ
What is the operating temperature range for the OPA349NA/3KG4?
The OPA349NA/3KG4 is specified for operation from 0°C to +70°C ambient temperature. Its electrical characteristics - including quiescent current, input offset voltage, and open-loop gain - are guaranteed across this range. The device can withstand storage temperatures from –65°C to +150°C, and junction temperature must not exceed 150°C during operation. For extended-range applications, consider the OPA349NA/3K.B variant rated from –40°C to +85°C.
Does the OPA349NA/3KG4 require external compensation for unity-gain stability?
No, the OPA349NA/3KG4 is internally compensated and unity-gain stable. It does not require external capacitors or resistors to maintain stability in gain-of-one configurations such as voltage followers or non-inverting buffers. This simplifies layout and reduces component count. Stability is verified across all load conditions up to 100pF capacitive load and 10kΩ resistive load, per TI SBOS121B datasheet Figure 8.
What package type and marking does the OPA349NA/3KG4 use?
The OPA349NA/3KG4 uses the SOT23-5 surface-mount package (TI package code DBV) with a 1.6mm × 2.9mm footprint and 1.1mm maximum height. Its top-side marking is "A49", laser-etched on the package body. The "/3KG4" suffix indicates tape-and-reel packaging with 3000 units per reel, RoHS-compliant NiPdAu lead finish, and moisture sensitivity level 2 (MSL-2, 260°C peak reflow).
Can the OPA349NA/3KG4 drive ADC inputs directly?
Yes, the OPA349NA/3KG4 can directly drive SAR and delta-sigma ADC inputs due to its rail-to-rail output swing (within 350mV of rails at 10kΩ load) and low output impedance. When driving switched-capacitor ADC inputs, a small series resistor (10–50Ω) is recommended to isolate the op amp from capacitive kickback. Its 70kHz GBW supports settling times <80µs for 0.01% accuracy on 1V steps - compatible with 100ksps ADC sampling rates.
How does the rail-to-rail input stage affect common-mode rejection in the OPA349NA/3KG4?
The OPA349NA/3KG4 uses complementary N-channel and P-channel input pairs to achieve rail-to-rail common-mode range, creating a 400mV transition region near (V+) – 1.3V where both pairs operate. Within this region, CMRR degrades from 72dB (outside transition) to ~46dB (full-range spec). For best CMRR, keep input common-mode voltage below (V+) – 1.5V. The datasheet provides separate CMRR specs for low-VCM and full-range conditions to guide design margining.
OPA349NA/3KG4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- SC-74A, SOT-753
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Discontinued at Digi-Key
- Amplifier Type:
- General Purpose
- Number of Circuits:
- 1
- Output Type:
- Rail-to-Rail
- Slew Rate:
- 0.02V/µs
- Gain Bandwidth Product:
- 70 kHz
- -3db Bandwidth:
- -
- Current - Input Bias:
- 0.5 pA
- Voltage - Input Offset:
- 2 mV
- Current - Supply:
- 1µA
- Current - Output / Channel:
- 8 mA
- Voltage - Supply Span (Min):
- 1.8 V
- Voltage - Supply Span (Max):
- 5.5 V
- Operating Temperature:
- 0°C ~ 70°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-23-5
OPA349NA/3KG4 FAQ
1.How can I place an order for OPA349NA/3KG4 through Aetrix?
Please submit a Request for Quotation (RFQ) for OPA349NA/3KG4 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 OPA349NA/3KG4 reliable?
The price and inventory of OPA349NA/3KG4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for OPA349NA/3KG4 is usually 5 days.
3.What payment methods are accepted for OPA349NA/3KG4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for OPA349NA/3KG4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for OPA349NA/3KG4?
OPA349NA/3KG4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your OPA349NA/3KG4 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 OPA349NA/3KG4?
For technical support, including OPA349NA/3KG4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your OPA349NA/3KG4 requirements.
6.How does Aetrix verify that OPA349NA/3KG4 is sourced from the original manufacturer or authorized distributors?
All OPA349NA/3KG4 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 OPA349NA/3KG4 meets industry standards.
7.What is the process for return or replacement of OPA349NA/3KG4?
All OPA349NA/3KG4 units undergo pre-shipment inspection (PSI). If there is an issue with OPA349NA/3KG4, 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 OPA349NA/3KG4 part is unused and in its original packaging.
Return procedure for OPA349NA/3KG4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
OPA349NA/3KG4 Tags
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