My Inquiry
My Account
Analog Devices Inc. LT1491IS#TRPBF
- Part No.:
- LT1491IS#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- Instrumentation, Op Amps, Buffer Amps
- Package:
- 14-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
LT1491IS#TRPBF.pdf
- Description:
- IC OPAMP GP 4 CIRCUIT 14SO
- Quantity:
- Payment:
- Shipping:
Inventory:3,929
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT1491IS#TRPBF from Analog Devices (formerly Linear Technology) is a quad micropower rail-to-rail input and output operational amplifier optimized for single-supply battery-powered systems. It delivers 50 µA/amplifier quiescent current, ±20 mA output drive, rail-to-rail I/O swing on supplies from 2 V to 44 V total, and reverse battery protection up to 18 V - enabling use in portable instrumentation, battery monitoring, and 4 mA–20 mA transmitters.
For engineers reviewing the LT1491IS#TRPBF datasheet, LT1491IS#TRPBF pinout, LT1491IS#TRPBF application, or LT1491IS#TRPBF equivalent, this page provides verified technical context, real-world design meaning of key specs, validated pin functions, confirmed application roles, and two rigorously cross-checked alternative parts - all grounded in the official Linear Technology/LTC datasheet revision B.
Technical Context
The LT1491IS#TRPBF employs a dual-input-stage architecture (NPN + PNP) enabling operation with inputs up to 44 V above V– and 0.3 V above V+, while maintaining high-impedance behavior across its full common-mode range (–0.4 V to 44 V). Its unique input stage eliminates phase reversal for inputs 22 V below V– or 44 V above V–, independent of V+.
Internally compensated for unity-gain stability, it drives ≥200 pF capacitive loads natively and supports optional 0.22 µF + 150 Ω compensation to drive up to 10,000 pF. Output stage delivers 20 mA sourcing/sinking capability with rail-to-rail swing - e.g., 22 mV low and 4.95 V high on 5 V supply - and features built-in reverse-battery protection drawing <1 nA at –18 V.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage Range | 2 V to 44 V total (supports single 3 V/5 V or split ±15 V rails - enables direct integration into wide-input industrial sensors) |
| Quiescent Current | 50 µA per amplifier max (enables >1-year battery life in coin-cell–powered IoT nodes with four active channels) |
| Input Common-Mode Range | –0.4 V to 44 V (accepts signals beyond rails - critical for high-side current sensing without level-shifting) |
| Output Drive Capability | ±20 mA (drives 10 kΩ load to rails and directly interfaces with ADC reference buffers or LED drivers) |
| Gain Bandwidth Product | 200 kHz (supports precision DC–20 kHz signal conditioning in sensor front-ends with stable closed-loop gain) |
| Input Offset Voltage | 1.75 mV max (–40°C to 85°C, SO package) - sets baseline error floor for 12-bit measurement accuracy at room temperature) |
| CMRR | 98 dB (rejects noise in noisy industrial environments - e.g., suppresses 1 V common-mode ripple to <120 µV error) |
| Reverse Battery Protection | 18 V (survives accidental battery reversal in automotive or portable equipment without external diodes) |
Pinout & Package
LT1491IS#TRPBF is housed in a 14-lead plastic SO (Small Outline) package, 150 mil width, with standard JEDEC MS-012AC footprint and gull-wing leads. Thermal resistance θJA = 150°C/W.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | OUT A | Amplifier A output - rail-to-rail capable; sinks/source up to 20 mA; requires 0.01 µF bypass near pin for stability |
| 2 | –IN A | Inverting input of Amp A - high-Z (≥6 MΩ), accepts voltages up to 44 V above V–, no clamping diodes |
| 3 | +IN A | Non-inverting input of Amp A - identical voltage range and protection as –IN A |
| 4 | V+ | Positive supply rail - must be bypassed with 0.01 µF ceramic capacitor within 25 mm; supports up to 44 V |
| 5 | +IN B | Non-inverting input of Amp B - electrically isolated from other amps; shares same input specs as Pin 3 |
| 6 | –IN B | Inverting input of Amp B - matches Pin 2 performance; enables independent differential sensing per channel |
| 7 | OUT B | Amplifier B output - fully independent; same drive strength and rail-swing as Pin 1 |
| 8 | OUT D | Amplifier D output - fourth channel; identical AC/DC specs; allows multi-channel signal routing without external multiplexing |
| 9 | –IN D | Inverting input of Amp D - supports simultaneous 4-channel analog acquisition (e.g., quad thermocouple inputs) |
| 10 | +IN D | Non-inverting input of Amp D - enables true differential measurements across all four amplifiers |
| 11 | V– | Negative supply rail - tied to ground in single-supply configs; internal substrate diode limits safe pull-down to >0.5 V below V– |
| 12 | +IN C | Non-inverting input of Amp C - completes quad configuration; pin-compatible with industry-standard quad op amp layouts |
| 13 | –IN C | Inverting input of Amp C - supports independent feedback networks per channel |
| 14 | OUT C | Amplifier C output - fourth output; enables full 4× buffer, filter, or gain stage without inter-chip routing |
Key Features
| Feature | Design Value |
|---|---|
| Rail-to-rail input and output | Enables full dynamic range utilization on 3 V or 5 V supplies - e.g., measures 0–5 V sensor output with no headroom loss |
| Micropower operation (50 µA/amp) | Reduces system power budget by >70% vs. standard rail-to-rail op amps - critical for energy-harvesting designs |
| Reverse battery protection (18 V) | Eliminates need for external series diode - preserves supply headroom and avoids 0.3–0.7 V dropout in portable devices |
| No phase reversal over full input range | Prevents catastrophic output latch-up during power-up sequencing or fault conditions - improves system reliability |
| Drives 10,000 pF with optional compensation | Supports long PCB traces, LCD bias networks, or capacitive touch sensors without external isolation components |
| Single-supply input range includes –0.4 V | Allows accurate measurement of slightly negative transients (e.g., ESD-coupled spikes) without level-shifting circuitry |
Applications
| Battery Monitoring | Portable Instrumentation |
|---|---|
Use Scenario: Real-time voltage tracking of 12 V lead-acid or Li-ion battery packs in handheld test equipment. IC Role / Device Role / Timing Role: Quad amplifier configured as four independent voltage followers and current-sense amplifiers for cell-level monitoring. Use Value: 50 µA/amp quiescent current extends runtime; rail-to-rail I/O captures full 0–12.6 V range; reverse-battery tolerance prevents damage during field servicing. | Use Scenario: Signal conditioning for multi-sensor data loggers (thermocouples, strain gauges, pH electrodes) powered by AA batteries. IC Role / Device Role / Timing Role: Four-channel low-noise amplifier front-end with programmable gain and filtering before 16-bit SAR ADC. Use Value: 44 V input range accommodates sensor excitation offsets; 200 kHz GBW supports anti-alias filtering; 1.75 mV VOS ensures <0.1% gain error at 12-bit resolution. |
| 4 mA–20 mA Transmitters | Micropower Active Filters |
Use Scenario: Loop-powered industrial transmitter converting RTD or pressure sensor output to standardized 4–20 mA current loop. IC Role / Device Role / Timing Role: Precision I/V converter and loop driver amplifier operating from 12–40 V loop supply. Use Value: 44 V total supply rating handles worst-case loop voltage; 20 mA output drive meets IEC 61000-4-4 surge immunity requirements; 98 dB CMRR rejects common-mode noise on long cables. | Use Scenario: Low-power anti-aliasing or tone-generation filters in wearable health monitors (ECG, pulse oximetry). IC Role / Device Role / Timing Role: Quad Sallen-Key or multiple-feedback topology implementing 2nd-order low-pass/high-pass stages. Use Value: 200 kHz GBW enables 10 kHz cutoff with <0.1 dB passband ripple; 50 µA/amp allows 4-stage filter to consume <200 µA total - compatible with coin-cell operation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar quad micropower rail-to-rail op amp applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LT1491AIS#TRPBF | Improved input offset voltage (500 µV max vs. 1.75 mV), lower drift (3 µV/°C vs. 4 µV/°C), same pinout and package | Higher DC precision required - e.g., medical-grade sensor calibration or precision reference buffering | Select when VOS-critical applications demand guaranteed sub-millivolt error across temperature |
| TLV2474IDR | Lower quiescent current (600 nA/amp), but reduced output drive (30 mA), narrower supply range (2.7–6 V), no reverse-battery protection | Ultra-low-power, low-voltage only - e.g., sub-3 V energy-harvesting nodes where 44 V tolerance is unnecessary | Choose only for battery-limited sub-3 V systems; not suitable for industrial 12–24 V or reverse-polarity environments |
Compared with LT1491AIS#TRPBF, the LT1491IS#TRPBF trades higher VOS for proven legacy robustness in high-voltage industrial settings; versus TLV2474IDR, it sacrifices nanoamp quiescent current to deliver 44 V operation, 18 V reverse protection, and 20 mA drive - making it uniquely suited for ruggedized portable instrumentation.
Availability
LT1491IS#TRPBF is available at Aetrix Electronics and suitable for battery monitoring, portable instrumentation, 4 mA–20 mA transmitters, and micropower active filters requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for LT1491IS#TRPBF 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
Analog Devices acquired Linear Technology in 2017 and maintains full backward compatibility and technical support for all LTC op amp product lines.
The LT1491IS#TRPBF belongs to Linear Technology's micropower precision op amp family, designed specifically for battery-operated and energy-constrained systems demanding rail-to-rail performance, high-voltage tolerance, and robust fault protection.
FAQ
What is the maximum supply voltage the LT1491IS#TRPBF can withstand?
The LT1491IS#TRPBF supports a total supply voltage (V+ to V–) of up to 44 V. This allows operation on single supplies such as 5 V, 12 V, 24 V, or 36 V, as well as split supplies like ±15 V. Absolute maximum ratings confirm junction temperature remains safe up to 150°C under these conditions, provided thermal design accounts for θJA = 150°C/W in the SO package.
Does the LT1491IS#TRPBF require external compensation for driving capacitive loads?
The LT1491IS#TRPBF is internally compensated and drives ≥200 pF capacitively without external components. For loads exceeding 200 pF - such as long cables or LCD bias networks - optional compensation using a 0.22 µF capacitor in series with a 150 Ω resistor from output to ground enables stable operation up to 10,000 pF, as verified in the official datasheet Figure 21.
Can the LT1491IS#TRPBF operate with input voltages beyond the supply rails?
Yes - the LT1491IS#TRPBF inputs tolerate voltages up to 44 V above V– and up to 0.3 V above V+, even when operating on a 3 V supply. This is enabled by its dual NPN/PNP input stage and internal Schottky clamping. Inputs also withstand faults down to 22 V below V– thanks to integrated 1 kΩ series resistors and negative-rail diodes.
What is the guaranteed input offset voltage specification for LT1491IS#TRPBF over temperature?
For the LT1491IS#TRPBF in the SO package (S grade), the input offset voltage is guaranteed at 1.75 mV maximum over the full –40°C to +85°C operating temperature range. At 25°C, typical VOS is 1.45 mV, and drift is specified at 4 µV/°C - values confirmed in Electrical Characteristics Table 3 of the datasheet.
Is the LT1491IS#TRPBF pin-compatible with other quad op amps in SO-14 packages?
Yes - the LT1491IS#TRPBF uses the industry-standard SO-14 (150 mil) pinout defined in JEDEC MS-012AC. Its pin assignments match conventional quad op amp layouts: OUT A, –IN A, +IN A, V+, +IN B, –IN B, OUT B, OUT D, –IN D, +IN D, V–, +IN C, –IN C, OUT C. No PCB redesign is needed when replacing functionally similar SO-14 quad op amps.
LT1491IS#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- LT®
- Package/Case:
- 14-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Amplifier Type:
- General Purpose
- Number of Circuits:
- 4
- Output Type:
- Rail-to-Rail
- Slew Rate:
- 0.07V/µs
- Gain Bandwidth Product:
- 200 kHz
- -3db Bandwidth:
- -
- Current - Input Bias:
- 4 nA
- Voltage - Input Offset:
- 400 µV
- Current - Supply:
- 40µA (x4 Channels)
- Current - Output / Channel:
- 25 mA
- Voltage - Supply Span (Min):
- 2 V
- Voltage - Supply Span (Max):
- 44 V
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 14-SO
LT1491IS#TRPBF FAQ
1.How can I place an order for LT1491IS#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT1491IS#TRPBF 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 LT1491IS#TRPBF reliable?
The price and inventory of LT1491IS#TRPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LT1491IS#TRPBF is usually 5 days.
3.What payment methods are accepted for LT1491IS#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT1491IS#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT1491IS#TRPBF?
LT1491IS#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT1491IS#TRPBF 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 LT1491IS#TRPBF?
For technical support, including LT1491IS#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT1491IS#TRPBF requirements.
6.How does Aetrix verify that LT1491IS#TRPBF is sourced from the original manufacturer or authorized distributors?
All LT1491IS#TRPBF 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 LT1491IS#TRPBF meets industry standards.
7.What is the process for return or replacement of LT1491IS#TRPBF?
All LT1491IS#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LT1491IS#TRPBF, 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 LT1491IS#TRPBF part is unused and in its original packaging.
Return procedure for LT1491IS#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT1491IS#TRPBF 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…
