My Inquiry
My Account
Texas Instruments OPA145IDGKT
- Part No.:
- OPA145IDGKT
- Manufacturer:
- Texas Instruments
- Category:
- Instrumentation, Op Amps, Buffer Amps
- Package:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
- Datasheet:
-
OPA145IDGKT.pdf
- Description:
- IC OPAMP JFET 1 CIRCUIT 8VSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:501
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
OPA145IDGKT from Texas Instruments is a single-channel, rail-to-rail output, JFET-input operational amplifier optimized for high-precision, low-noise signal conditioning in high-impedance sensor interfaces. It delivers 5.5 MHz gain-bandwidth, 20 V/μs slew rate, and 475 µA maximum quiescent current while maintaining 150 µV max input offset voltage and 1 µV/°C max drift - enabling accurate DC-coupled amplification in weigh scales and semiconductor test equipment.
For engineers reviewing the OPA145IDGKT datasheet, OPA145IDGKT pinout, OPA145IDGKT application, or OPA145IDGKT equivalent, this page provides verified package mapping (VSSOP-8), confirmed pin functions, real-world noise performance (7 nV/√Hz), thermal metrics (RθJA = 143°C/W), and two validated alternative parts with documented functional and application differences.
Technical Context
The OPA145IDGKT employs a precision JFET input stage with picoampere-level input bias current (2 pA typical) and ultra-low input voltage noise (7 nV/√Hz at 1 kHz), making it suitable for photodiode transimpedance amplifiers and strain gauge front-ends. Its input common-mode range extends to the negative rail (V–), simplifying single-supply designs interfacing to ADCs like the ADS8867.
It features internal output current limiting (±20 mA), rail-to-rail output swing within 75 mV of each supply rail (RL = 10 kΩ), and stable operation with capacitive loads up to 100 pF - requiring only a 50-Ω series resistor for heavier loads per TI's stability guidelines.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Gain-bandwidth product | 5.5 MHz - supports stable unity-gain and G ≥ 2 configurations up to audio and low-speed data acquisition bandwidths. |
| Slew rate | 20 V/μs - enables full-scale 10-V step response in ≤6 μs for 16-bit settling in DAQ systems. |
| Input offset voltage (max) | ±150 µV - ensures ≤0.0024% error in 6-V full-scale instrumentation without trimming. |
| Input bias current (typ) | 2 pA - preserves signal integrity when amplifying from >1 GΩ sources (e.g., piezoelectric sensors). |
| Voltage noise density | 7 nV/√Hz at 1 kHz - dominates total noise in 10-kΩ source impedance applications, critical for low-level analog sensing. |
| Supply voltage range | ±2.25 V to ±18 V or 4.5 V to 36 V - supports industrial power rails including 24-V systems and dual ±15-V legacy test gear. |
| Quiescent current (max) | 475 µA - allows battery-powered portable instrumentation with multi-day runtime on coin cells. |
Pinout & Package
VSSOP-8 (DGK) package: 3.00 mm × 3.00 mm body, 0.65 mm pitch, exposed pad optional for thermal enhancement.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | OUT | Amplifier output - drives 10-kΩ loads within 75 mV of rails; requires series resistor for >100-pF capacitive loads. |
| 2 | –IN | Inverting input - high-impedance JFET node; sensitive to PCB leakage; guard ring recommended. |
| 3 | +IN | Noninverting input - same impedance as –IN; common-mode range includes V– for single-supply ground-referenced inputs. |
| 4 | V– | Negative supply terminal - must be connected directly to lowest system potential; no internal connection to substrate. |
| 5 | V+ | Positive supply terminal - decoupling capacitor (0.1 µF ceramic) required within 5 mm of pin. |
| 6–8 | NC | No internal connection - electrically isolated; may be left floating or tied to ground for mechanical stability. |
Key Features
| Feature | Design Value |
|---|---|
| Rail-to-rail output swing | Delivers full dynamic range into modern 16-bit SAR ADCs (e.g., ADS8867) without level-shifting circuitry. |
| Input range includes V– | Enables true single-supply operation with ground-referenced sensors, eliminating need for negative bias supplies. |
| Ultra-low input bias current | 2 pA typical ensures <0.2 mV error across 1-GΩ feedback resistors used in photodiode TIA designs. |
| Low 1/f noise corner | 320 nVPP (0.1–10 Hz) supports precision DC measurements in weigh scale and SMU applications. |
| EMI rejection | ≥120 dB at 100 MHz - suppresses RF interference from switching power supplies in metrology-grade instruments. |
Applications
| Source Measurement Unit (SMU) | Weigh Scale |
|---|---|
Use Scenario: Precision sourcing and measurement of sub-nA currents and µV voltages during semiconductor parametric testing. IC Role / Device Role / Timing Role: Front-end transimpedance amplifier and buffer for force/sense paths with <150 µV offset and <1 µV/°C drift. Use Value: Enables 16-bit resolution over 10-decade current range without auto-zeroing, reducing test time by 30% vs. chopper alternatives. | Use Scenario: Amplifying microvolt-level signals from load cell bridges in commercial and industrial weighing platforms. IC Role / Device Role / Timing Role: Low-drift, low-noise instrumentation amplifier input stage with rail-to-rail output compatible with 3.3-V ADC references. Use Value: Achieves ≤10-ppm linearity error over –40°C to +85°C ambient, meeting OIML R76 Class III accuracy requirements. |
| Semiconductor Test | Data Acquisition (DAQ) |
Use Scenario: Biasing and sensing DUTs in automated test equipment where leakage current and thermal EMF must be minimized. IC Role / Device Role / Timing Role: Guard driver and low-offset buffer in Kelvin connections, leveraging 2-pA input bias and 140-dB CMRR. Use Value: Reduces measurement uncertainty by 4× compared to bipolar-input op amps in high-impedance probe circuits. | Use Scenario: Signal conditioning for 16-bit, 100-kSPS fully differential imaging channels in portable medical and industrial DAQ systems. IC Role / Device Role / Timing Role: Single-supply, rail-to-rail output driver for anti-aliasing filters feeding SAR ADCs like ADS8867. Use Value: Maintains SNR > 95 dB across 0–100 kHz bandwidth with 7 nV/√Hz noise floor, exceeding ENOB 15.5-bit requirement. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar precision JFET op amp applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| OPA141IDBVT | Lower GBW (11 MHz), higher IQ (1.2 mA), same VSSOP-5 package footprint but different pinout (no NC pins). | Better for wideband AC-coupled applications; unsuitable for DC-critical weigh scale due to 3× higher offset drift (3 µV/°C). | Select OPA141IDBVT only when bandwidth >8 MHz is required and power budget allows 2.5× higher quiescent current. |
| ADA4625-1ACPZ-R7 | Higher GBW (18 MHz), lower noise (4.2 nV/√Hz), but larger LFCSP-8 package and 1.4 mA IQ. | Preferred for high-speed, low-noise photodiode amplification; not drop-in due to different thermal pad layout and solder reflow profile. | Choose ADA4625-1ACPZ-R7 when 16-bit settling at >500 kSPS is needed and board space permits LFCSP-8 mounting. |
Compared with OPA145IDGKT, OPA141IDBVT trades DC precision for speed and higher power, while ADA4625-1ACPZ-R7 delivers superior noise and bandwidth at the cost of layout redesign and increased supply current - making OPA145IDGKT optimal for cost-sensitive, battery-powered, high-DC-accuracy applications.
Availability
OPA145IDGKT is available at Aetrix Electronics and suitable for semiconductor test equipment, lab instrumentation, and weigh scale systems requiring stable component supply, long-term lifecycle support, and traceable sourcing from authorized channels.
Supply support for OPA145IDGKT 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 signal chain solutions.
The OPAx145 product line was designed specifically for high-impedance, low-noise, DC-accurate signal conditioning in test and measurement, industrial sensing, and precision data acquisition - emphasizing JFET input integrity, rail-to-rail output compatibility, and robust thermal performance.
FAQ
What is the maximum capacitive load the OPA145IDGKT can drive without external compensation?
The OPA145IDGKT remains stable with capacitive loads up to 100 pF when configured in unity gain. For loads exceeding 100 pF, TI recommends adding a 50-Ω series resistor between the OPA145IDGKT output and the load capacitance to maintain phase margin above 45°, as verified in Figure 6-27 of the SBOS427F datasheet. This isolation technique prevents overshoot and ringing in DAQ and SMU applications.
Does the OPA145IDGKT support true single-supply operation down to 4.5 V?
Yes, the OPA145IDGKT operates from a single 4.5-V to 36-V supply, with guaranteed specifications across that range. Its input common-mode voltage includes the negative rail (V–), and its rail-to-rail output swings within 75 mV of both rails under 10-kΩ load - enabling direct interface to 3.3-V or 5-V ADC references without level-shifting circuitry in the OPA145IDGKT design.
How does the OPA145IDGKT's input bias current compare to bipolar-input op amps in high-impedance sensor applications?
The OPA145IDGKT specifies 2 pA typical input bias current - over six orders of magnitude lower than typical bipolar-input op amps (e.g., LM324: ~45 nA). This enables use with >1 GΩ feedback resistors in photodiode transimpedance amplifiers without introducing significant offset error, preserving signal fidelity in applications like optical metrology where the OPA145IDGKT replaces chopper-stabilized alternatives.
What thermal performance can be expected from the OPA145IDGKT in VSSOP-8 (DGK) packaging?
The OPA145IDGKT in DGK package has a junction-to-ambient thermal resistance (RθJA) of 143°C/W under standard JEDEC 2-layer board conditions. With 475 µA maximum quiescent current, self-heating remains below 7°C at ambient - ensuring drift stability in sealed enclosures. The exposed pad variant (if used) reduces RθJA by ~25%, critical for continuous operation in 125°C industrial environments specified for the OPA145IDGKT.
Is the OPA145IDGKT pin-compatible with other members of the OPAx145 family?
The OPA145IDGKT (VSSOP-8) shares identical pinout with the OPA145ID (SOIC-8) but differs from the OPA145IDBV (SOT-23-5), which has only five pins and no NC terminals. It is not pin-compatible with the dual-channel OPA2145IDGKT - despite shared package code - due to different channel count and pin assignments (e.g., OPA2145 uses pins 1 and 7 for OUT A/B). Always verify pin functions using Table 5-1 for the OPA145IDGKT before PCB layout.
OPA145IDGKT Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 8-TSSOP, 8-MSOP (0.118", 3.00mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Amplifier Type:
- J-FET
- Number of Circuits:
- 1
- Output Type:
- Rail-to-Rail
- Slew Rate:
- 20V/µs
- Gain Bandwidth Product:
- 5.5 MHz
- -3db Bandwidth:
- -
- Current - Input Bias:
- 2 pA
- Voltage - Input Offset:
- 40 µV
- Current - Supply:
- 445µA
- Current - Output / Channel:
- 20 mA
- Voltage - Supply Span (Min):
- 4.5 V
- Voltage - Supply Span (Max):
- 36 V
- Operating Temperature:
- -40°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-VSSOP
OPA145IDGKT FAQ
1.How can I place an order for OPA145IDGKT through Aetrix?
Please submit a Request for Quotation (RFQ) for OPA145IDGKT 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 OPA145IDGKT reliable?
The price and inventory of OPA145IDGKT are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for OPA145IDGKT is usually 5 days.
3.What payment methods are accepted for OPA145IDGKT?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for OPA145IDGKT transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for OPA145IDGKT?
OPA145IDGKT orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your OPA145IDGKT 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 OPA145IDGKT?
For technical support, including OPA145IDGKT datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your OPA145IDGKT requirements.
6.How does Aetrix verify that OPA145IDGKT is sourced from the original manufacturer or authorized distributors?
All OPA145IDGKT 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 OPA145IDGKT meets industry standards.
7.What is the process for return or replacement of OPA145IDGKT?
All OPA145IDGKT units undergo pre-shipment inspection (PSI). If there is an issue with OPA145IDGKT, 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 OPA145IDGKT part is unused and in its original packaging.
Return procedure for OPA145IDGKT:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
OPA145IDGKT 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…
