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Texas Instruments OPA349UA
- Part No.:
- OPA349UA
- Manufacturer:
- Texas Instruments
- Category:
- Instrumentation, Op Amps, Buffer Amps
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
OPA349UA.pdf
- Description:
- IC OPAMP GP 1 CIRCUIT 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:4,855
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Product details
Overview
OPA349UA from Texas Instruments is a single-channel, rail-to-rail input/output CMOS operational amplifier optimized for ultra-low-power battery-operated 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 smoke detectors, solar-powered sensors, and portable instrumentation.
For engineers reviewing the OPA349UA datasheet, OPA349UA pinout, OPA349UA application, or OPA349UA equivalent, key selection criteria include its 1µA supply current, rail-to-rail I/O swing (±350mV of rails), 10pA max input bias current, unity-gain stability, and SO-8 package compatibility with space-constrained PCB layouts.
Technical Context
The OPA349UA employs a complementary differential input stage enabling rail-to-rail common-mode input range extending 200mV beyond both supply rails. Its CMOS architecture ensures low input bias current (≤10pA) and high input impedance (10¹³ Ω || 4 pF), supporting high-value feedback networks without significant error.
It features unity-gain stable internal compensation, eliminating external components for G = +1 configurations. Output drive capability is ±8mA into resistive loads, with output voltage swing limited to within 350mV of either rail at 10kΩ load - critical for maximizing dynamic range in low-voltage, single-supply systems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage Range | 1.8V to 5.5V - supports operation across declining battery voltages without performance loss. |
| Quiescent Current | 1µA (typ) - enables multi-year battery life in always-on remote sensors and smoke detectors. |
| Gain-Bandwidth Product | 70kHz - sufficient for DC–audio-frequency sensor amplification and anti-aliasing filtering. |
| Input Bias Current | ≤10pA (max) - permits use of >10MΩ source/feedback resistors without offset drift. |
| Input Common-Mode Range | (V−) − 0.2V to (V+) + 0.2V - allows direct sensing of signals near supply rails, e.g., battery voltage monitoring. |
| Output Swing (10kΩ) | Within 350mV of rails - preserves >70% of full-scale dynamic range at 3.3V supply. |
| Open-Loop Gain | 90dB (min 74dB) - ensures <0.1% gain error in precision buffer and gain-of-10 configurations. |
Pinout & Package
OPA349UA is housed in an 8-pin SOIC (D) surface-mount package with standard JEDEC outline (D0008A), 1.75mm max height, and 1.27mm lead pitch. Thermal resistance θJA is 150°C/W.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (NC) | No internal connection | Unused pin; must be left floating or tied to ground per layout best practice. |
| 2 (V+) | Positive supply | Connect to main system supply (1.8–5.5V); bypass with 0.01µF ceramic capacitor. |
| 3 (Out) | Amplifier output | Delivers rail-to-rail swing; capable of ±8mA drive into resistive loads. |
| 4 (NC) | No internal connection | Unused pin; no electrical function; avoid routing traces to this pad. |
| 5 (NC) | No internal connection | Unused pin; electrically isolated; may be used as thermal pad anchor if grounded. |
| 6 (−In) | Inverting input | Differential input node; high-impedance CMOS input (10¹³ Ω) with ≤10pA bias current. |
| 7 (+In) | Non-inverting input | Differential input node; identical impedance and bias characteristics as −In. |
| 8 (V−) | Negative supply / Ground | Reference node for single-supply operation; connect to system ground or negative rail. |
Key Features
| Feature | Design Value |
|---|---|
| Rail-to-rail input range | Extends 200mV beyond supply rails - enables accurate measurement of signals near V+ or V− without level-shifting circuitry. |
| Unity-gain stable | No external compensation required - simplifies design of buffers, active filters, and gain stages at G = +1. |
| Ultra-low quiescent current | 1µA typical - reduces total system power budget by >90% vs. conventional op amps in always-on sensing nodes. |
| Wide supply voltage range | 1.8V to 5.5V - maintains specification compliance across alkaline, Li-ion, and coin-cell battery discharge curves. |
| Low input bias current | ≤10pA - minimizes voltage drop across high-impedance sensor elements (e.g., thermistors, pH electrodes). |
Applications
| Battery-Powered Smoke Detection | Solar-Powered Remote Sensor Node |
|---|---|
Use Scenario: Amplifying weak ionization chamber current (pA–nA) in low-power smoke alarms operating on AA batteries for >5 years. IC Role / Device Role / Timing Role: Precision transimpedance amplifier with ultra-low input bias current and rail-to-rail output swing to maximize ADC utilization. Use Value: 10pA max input bias avoids signal corruption; 1µA quiescent current extends battery life; rail-to-rail output ensures full 0–3.3V ADC range usage. | Use Scenario: Signal conditioning for photodiode or temperature sensor in off-grid environmental monitor powered by small solar panel + supercapacitor. IC Role / Device Role / Timing Role: Low-power sensor interface amplifier driving SAR ADC input with minimal standby power draw. Use Value: 1.8V minimum supply allows operation during low-light conditions; 70kHz bandwidth suffices for slow-varying environmental parameters; SO-8 package enables robust reflow assembly. |
| Portable Medical Pulse Oximeter | PCMCIA Card Analog Front-End |
Use Scenario: Amplifying red/IR photodiode signals in battery-powered pulse oximeters requiring continuous 24/7 operation. IC Role / Device Role / Timing Role: Dual-stage DC-coupled amplifier with rail-to-rail I/O to preserve signal fidelity across varying tissue perfusion levels. Use Value: Input range extending 200mV beyond rails captures full LED turn-on transient; 90dB open-loop gain ensures <0.05% gain error in calibrated SpO₂ calculation. | Use Scenario: Signal buffering and level-shifting for analog inputs/outputs on PCMCIA cards used in industrial data acquisition modules. IC Role / Device Role / Timing Role: Isolation and drive amplifier between card-edge connector and onboard ADC/DAC. Use Value: SO-8 package matches standard PCMCIA board thickness constraints; 8mA output drive supports 50Ω trace termination; 150°C/W θJA enables thermal management in dense card layouts. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar ultra-low-power op amp applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TLV2401CDR | Same 1µA IQ, but 5.5kHz GBW (vs. 70kHz); lower open-loop gain (80dB); SC70-5 only. | Limited to sub-audio applications; insufficient for fast-settling sensor filters or A/D driver circuits requiring >10kHz bandwidth. | Select TLV2401CDR only when bandwidth demand is <6kHz and SC70 footprint is mandatory. |
| OPA347UA | 20µA IQ (20× higher); 500kHz GBW; same SO-8 package; wider temp range (−40°C to +85°C). | Higher power consumption disqualifies it for multi-year battery use, but enables faster response in active filter or comparator hysteresis circuits. | Choose OPA347UA when system requires >100kHz bandwidth and can tolerate 20µA standby current. |
Compared with TLV2401CDR and OPA347UA, the OPA349UA uniquely balances micropower efficiency (1µA) with usable bandwidth (70kHz) and rail-to-rail I/O in SO-8 - making it optimal for long-life, low-voltage sensor interfaces where both precision and energy economy are non-negotiable.
Availability
OPA349UA is available at Aetrix Electronics and suitable for battery packs, smoke/fire detection systems, and solar-powered remote sensors requiring stable component supply with guaranteed long-term availability and consistent parametric performance.
Supply support for OPA349UA 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 amplifiers and low-power design.
The OPA349 series belongs to TI's precision micropower op amp product line, engineered specifically for extended-battery-life applications demanding rail-to-rail operation, ultra-low IQ, and robust performance across wide supply and temperature ranges.
FAQ
What is the operating temperature range for the OPA349UA?
The OPA349UA is specified for operation from 0°C to +70°C, with extended functionality up to +85°C. This range aligns with commercial-grade requirements for portable electronics and indoor environmental sensors. The SO-8 package's θJA of 150°C/W supports reliable thermal performance under typical PCB copper pour conditions. Always verify ambient temperature limits in your final enclosure design before deploying OPA349UA.
Does the OPA349UA require external compensation for unity-gain stability?
No, the OPA349UA is internally compensated and unity-gain stable - no external capacitors or resistors are needed for G = +1 configurations. This simplifies design of voltage followers and active filters. However, when driving capacitive loads >100pF, a small series resistor (10–50Ω) at the output is recommended to maintain phase margin, as confirmed in the OPA349UA datasheet Figure 8 small-signal overshoot plots.
Can the OPA349UA operate from a 1.8V single supply?
Yes, the OPA349UA is fully specified and tested from 1.8V to 5.5V single supply. At 1.8V, it maintains 70kHz GBW, 1µA quiescent current, and rail-to-rail input/output swing - enabling direct interfacing with low-voltage microcontrollers and energy-harvesting systems. Electrical characteristics tables in the SBOS121B datasheet explicitly list performance at 1.8V, confirming functional integrity across the entire range.
What is the maximum output current capability of the OPA349UA?
The OPA349UA delivers ±8mA output current into resistive loads, with short-circuit current rated at ±10mA. This is sufficient to drive 12-bit SAR ADC reference buffers, LED bias circuits, and moderate-impedance sensor excitation networks. Note that output swing degrades to within 350mV of rails at 10kΩ load - ensure downstream loading remains within this limit to preserve dynamic range. Full details appear in the "OUTPUT" section of the OPA349UA electrical characteristics table.
How does the rail-to-rail input stage of the OPA349UA affect common-mode rejection?
The OPA349UA uses complementary N- and P-channel input pairs to achieve rail-to-rail common-mode range, resulting in a 400mV transition region near (V+) − 1.3V where both pairs conduct. Within this region, CMRR degrades from 72dB to ~46dB. For best performance, keep common-mode voltage outside this zone - e.g., bias non-inverting input at mid-supply using high-value resistors. This behavior is documented in the "COMMON-MODE REJECTION" application note section of the OPA349UA datasheet.
OPA349UA Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- 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:
- 8-SOIC
OPA349UA FAQ
1.How can I place an order for OPA349UA through Aetrix?
Please submit a Request for Quotation (RFQ) for OPA349UA 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 OPA349UA reliable?
The price and inventory of OPA349UA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for OPA349UA is usually 5 days.
3.What payment methods are accepted for OPA349UA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for OPA349UA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for OPA349UA?
OPA349UA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your OPA349UA 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 OPA349UA?
For technical support, including OPA349UA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your OPA349UA requirements.
6.How does Aetrix verify that OPA349UA is sourced from the original manufacturer or authorized distributors?
All OPA349UA 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 OPA349UA meets industry standards.
7.What is the process for return or replacement of OPA349UA?
All OPA349UA units undergo pre-shipment inspection (PSI). If there is an issue with OPA349UA, 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 OPA349UA part is unused and in its original packaging.
Return procedure for OPA349UA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
OPA349UA Tags
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