OPA128LM Texas Instruments Integrated Circuit (Other) In Stock
Texas Instruments OPA128LM is a precision electrometer-grade operational amplifier with ultra-low bias current of 75 fA and 1 MHz bandwidth in an 8-pin TO-99 metal can package. It features 90 dB minimum CMRR and 750 µV maximum input offset voltage for accurate low-level signal amplification. Available from stock with worldwide shipping.
- Manufacturer
- Texas Instruments
- Package
- Other
- Pin Count
- 8
- Lifecycle
- OBSOLETE
- Datasheet
- OPA128LM Datasheet PDF
- Category
- Integrated Circuit
- Temp Range
- ?°C to 70.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
What are the key features of OPA128LM?
- Ultra-low bias current of 75 fA (max 7.5e-8 µA at 25°C) enabling accurate amplification of high-impedance electrometer-grade signal sources
- 1 MHz gain-bandwidth product with internal frequency compensation supporting stable unity-gain operation without external components
- 90 dB minimum (112 dB typical) CMRR rejecting common-mode noise for precise differential measurement in noisy environments
- 8-pin TO-99 hermetic metal can package providing excellent shielding, low leakage currents, and superior environmental protection for lab and industrial use
What is OPA128LM used for?
The OPA128LM is used in electrometer circuits, photodiode amplifiers, and ionization detector front-ends where source impedance exceeds 1 GΩ and bias current must remain below 100 fA. Its 112 dB typical CMRR and 750 µV offset make it suitable for precision instrumentation, medical biosignal amplifiers, and analytical chemistry equipment. The hermetic TO-99 package ensures stable long-term performance in controlled environment scientific instruments.
What are the specifications of OPA128LM?
| Pbfree Code | Yes |
| YTEOL | 0 |
| Amplifier Type | OPERATIONAL AMPLIFIER |
| Architecture | VOLTAGE-FEEDBACK |
| Average Bias Current-Max (IIB) | 0.000002 µA |
| Bias Current-Max (IIB) @25C | 7.5e-8 µA |
| Common-mode Reject Ratio-Min | 90dB |
| Common-mode Reject Ratio-Nom | 112dB |
| Frequency Compensation | YES |
| Input Offset Voltage-Max | 750 µV |
| JESD-30 Code | O-MBCY-W8 |
| Low-Bias | YES |
| Low-Offset | YES |
| Micropower | NO |
| Neg Supply Voltage Limit-Max | -18 V |
| Neg Supply Voltage-Nom (Vsup) | -15 V |
| Number of Functions | 1 |
| Package Body Material | METAL |
| Package Equivalence Code | CAN8,.2 |
| Package Shape | ROUND |
| Package Style | CYLINDRICAL |
| Packing Method | TUBE |
| Peak Reflow Temperature (Cel) | NOT SPECIFIED |
| Power | NO |
| Programmable Power | NO |
| Qualification Status | Not Qualified |
| Slew Rate-Min | 1V/us |
| Slew Rate-Nom | 3V/us |
| Supply Current-Max | 3.6mA |
| Supply Voltage Limit-Max | 18V |
| Supply Voltage-Nom (Vsup) | 15V |
| Surface Mount | NO |
| Technology | BIPOLAR |
| Temperature Grade | COMMERCIAL |
| Terminal Form | WIRE |
| Terminal Position | BOTTOM |
| Time@Peak Reflow Temperature-Max (s) | NOT SPECIFIED |
| Unity Gain BW-Nom | 1000 |
| Voltage Gain-Min | 160000 |
| Wideband | NO |
| Package | Other |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8542.33.00.01 |
Where can I find the OPA128LM datasheet?
OPA128LM Datasheet DownloadOfficial datasheet from Texas Instruments
What are equivalent replacements for OPA128LM?
No known alternates. Submit an RFQ and our team can suggest alternatives.
Frequently Asked Questions
What makes OPA128LM suitable for high-impedance electrometer measurements at nanowatt signal levels?
The OPA128LM achieves a maximum input bias current of 75 fA (7.5e-8 µA at 25°C), which is among the lowest available in a commercial op-amp. This enables accurate current-to-voltage conversion from sources with impedances above 1 GΩ, such as pH electrodes, ionization chambers, and photodiodes, where even picoamp bias currents would corrupt the measurement.
How does the TO-99 hermetic package benefit OPA128LM in precision lab instrumentation?
The TO-99 hermetic metal can package of OPA128LM provides a sealed metal enclosure that eliminates moisture ingress and reduces surface leakage currents to below 1 fA, critical for maintaining 75 fA bias current specifications. The metal can also shields the die from light-induced photocurrents and RF interference, making it preferred in analytical instruments, electrometers, and scientific measurement systems.
What CMRR performance does the OPA128LM provide, and when does it matter in circuit design?
The OPA128LM provides a minimum CMRR of 90 dB and a typical CMRR of 112 dB. This level of common-mode rejection is essential in differential measurement circuits powered from noisy supplies, biomedical amplifiers processing millivolt-level biosignals, and precision strain-gauge bridges where 60 Hz power-line interference must be attenuated by more than 90 dB to preserve signal accuracy.
Can OPA128LM operate stably at unity gain without external compensation components?
Yes. The OPA128LM includes internal frequency compensation, providing stable unity-gain operation with a 1 MHz gain-bandwidth product without requiring any external compensation network. This simplifies circuit design for voltage followers and non-inverting buffers in precision amplifier chains, reducing component count and potential noise pickup from external passive elements.
Related Guides
CSD87313DMS Synchronous Buck Power Stage Design Guide
Design a compact CSD87313DMS synchronous buck stage with practical guidance for loss, gate drive, PCB layout, EMI, thermal validation, and sourcing.
Aug 6, 2026
STEF05SGR eFuse Selection Guide for 5 V Overcurrent Protection
Choose STEF05SGR for 5 V overcurrent protection by checking current-limit margin, inrush, thermal loss, fault response, and sourcing.
Aug 6, 2026
C0402C103K3RACTU Selection Guide: Choosing a 10 nF 0402 MLCC
Select C0402C103K3RACTU by voltage margin, X7R behavior, tolerance, 0402 assembly risk, and qualified alternatives.
Aug 4, 2026
STM32H753VIT6 MCU Selection Guide: Memory, Package, Connectivity, and Security
Choose STM32H753VIT6 by evaluating memory architecture, LQFP-100 pin fit, connectivity, security, power, and sourcing tradeoffs.
Aug 4, 2026
Why Buy from FindMyChip
About Texas Instruments
Texas Instruments (TI) is a global semiconductor company headquartered in Dallas, Texas. TI designs and manufactures analog and embedded processing chips used in industrial, automotive, consumer, communications, and enterprise systems.
More from Texas Instruments
In Stock · 24h Response · Worldwide Shipping
Response within 24 hours · Worldwide shipping
“Response time is incredible — usually under 4 hours. They understand that production lines can't wait.”
You May Also Like
ACS770ECB-200U-PFF-T
Allegro Microsystems
Integrated Circuit
ACS770KCB-150U-PFF-T
Allegro Microsystems
Integrated Circuit
MC33901WEF
NXP
Integrated Circuit
MC7808BDTRKG
ON Semiconductor
Integrated Circuit
PA94EC
Apex Microtechnology
Integrated Circuit
AP7315-28SR-7
Diodes Inc.
Integrated Circuit
74HCT245D
Nexperia
Integrated Circuit
CY62256VNLL-70ZXCT
Cypress Semiconductor
Integrated Circuit
EPM7032AETC44-4N
Intel
Integrated Circuit
EPM3512AQC208-10N
Intel
Integrated Circuit
EPM3256ATC144-7N
Intel
Integrated Circuit
EPM3256AQC208-7N
Intel
Integrated Circuit
EPM3256AQC208-10N
Intel
Integrated Circuit
EPM3128ATC100-7N
Intel
Integrated Circuit
EPM1270F256C4N
Intel
Integrated Circuit
EPF8282ATC100-4N
Intel
Integrated Circuit
EPF6016QC208-2N
Intel
Integrated Circuit
EPF6016ATC144-3N
Intel
Integrated Circuit
EPF10K30ATC144-3N
Intel
Integrated Circuit
EPC2TI32N
Intel
Integrated Circuit
EPC2LC20
Intel
Integrated Circuit
EP3SL150F1152C4N
Intel
Integrated Circuit
EP2SGX60DF780C5N
Intel
Integrated Circuit
EP2SGX60CF780C5N
Intel
Integrated Circuit