INA118PB - Precision Instrumentation Amplifier | Texas Instruments
MPN: INA118PB ✓ Hoạt độngINA118PB Tóm tắt
An instrumentation amplifier is a specialized analog amplifier designed to accurately amplify small differential signals while rejecting large common-mode voltages. Its internal three-op-amp architecture and current-feedback input stage provide high input impedance, stable gain, and useful bandwidth at high closed-loop gains. The INA118 belongs to the broader hierarchy of differential amplifier, instrumentation amplifier, analog amplifier, and semiconductor.
The INA118PB is laser trimmed for low offset voltage and low temperature drift, while its internal input protection supports inputs to ±40 V. A single external gain-setting resistor provides gains from 1 to 10,000. According to the Texas Instruments product page, bandwidth remains 70 kHz at a gain of 100, while the low 350 uA quiescent current makes the device suitable for battery-operated and portable measurement systems.
The three-op-amp internal design simplifies instrumentation-amplifier implementation while maintaining precision over the specified temperature range of -40°C to +85°C. Differential inputs minimize sensitivity to common-mode noise, and the low-offset architecture improves accuracy in bridge, shunt, and sensor-interface circuits. Its low-power operation is particularly valuable when every milliamp of supply current affects battery life or thermal design.
Typical uses include bridge-amplifier interfaces, current-shunt measurements, precision sensor conditioning, biomedical instrumentation, industrial process monitoring, and low-noise battery-powered acquisition systems. The protected inputs can improve resilience to accidental signal-chain overvoltage, although the design must still maintain valid supply and common-mode conditions for accurate operation.
Designers should place the gain resistor close to the RG pins, route differential inputs symmetrically, and provide local supply bypassing. Input filtering must account for the protected input network and noise requirements, while PCB cleanliness is important because high-gain measurements amplify small residual errors. The 8-pin plastic DIP format is suitable for through-hole prototypes, legacy systems, and automated test fixtures.
This page combines verified Texas Instruments specifications, distributor availability, same-package drop-in alternatives, and practical engineering guidance. It adds design-focused context for gain selection, bandwidth, input protection, supply bypassing, and PCB implementation that is not directly visible in a distributor listing.
Bộ thay thế dễ dàng lắp đặt cho INA118PB — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với INA118PB (cùng hình factor và footprint) — khác nhau ở Quiescent Current, Product Type, Architecture, Package, Gain Range.
INA118P
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →INA126P
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →INA128P
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →INA120P
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
INA149P
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
INA118PB Tỷ lệ tối đa & tính chất điện
| Product Type | Precision instrumentation amplifier |
| Number of Amplifiers | 1 circuit |
| Architecture | Three-op-amp design |
| Maximum Offset Voltage | 50 uV |
| Maximum Offset Voltage Drift | 0.5 uV/°C |
| Maximum Input Bias Current | 5 nA |
| Minimum Common-Mode Rejection | 110 dB at G = 1000 |
| Maximum Input Voltage | ±40 V |
| Maximum Supply Voltage | ±18 V |
| Minimum Single-Supply Voltage | 1.35 V |
| Minimum Dual-Supply Voltage | ±2.25 V |
| Điện áp yên tĩnh | 350 uA |
| Gain Range | 1 to 10,000 |
| Bandwidth at Gain of 100 | 70 kHz |
| Khoảng nhiệt độ hoạt động | -40°C to +85°C |
| Hộp | 8-pin plastic DIP |
| Kiểu lắp đặt | Through-hole |
Cấu hình chân INA118PB
| Chân 1 | RG — Gain-setting resistor terminal |
| Chân 2 | IN− — Inverting input |
| Chân 3 | IN+ — Non-inverting input |
| Chân 4 | V− — Negative supply terminal |
| Chân 5 | REF — Reference input |
| Chân 6 | OUT — Amplified output |
| Chân 7 | VS — Positive supply terminal |
| Chân 8 | RG — Gain-setting resistor terminal |
Ứng dụng tiêu biểu
INA118PB phù hợp cho 6 Áp dụngs: Precision Bridge Sensor Interface, Battery-Powered Data Acquisition, Current Shunt Measurement, Medical Signal Conditioning, Industrial Process Monitoring, Precision Sensor and Transducer Interface.
Precision Bridge Sensor Interface
The INA118PB fits precision bridge measurements because its 50 uV maximum offset, 5 nA maximum input bias current, and 110 dB minimum common-mode rejection at a gain of 1000 help preserve small differential signals from resistive sensors. Place the bridge output across the IN− and IN+ inputs and use one external resistor to establish the required gain from 1 to 10,000. Differential routing and matched input components are important because high gain also amplifies resistor mismatch, leakage, and thermoelectric errors. The 70 kHz bandwidth specified at a gain of 100 provides useful response for many pressure, load, and position systems, although bandwidth and noise must be balanced against measurement speed.
Được đề xuất
Battery-Powered Data Acquisition
The INA118PB is appropriate for battery-powered acquisition systems because its quiescent current is only 350 uA while the device supports supplies down to 1.35 V. A dual-supply implementation can operate from ±2.25 V, while higher rails remain available for industrial systems. The amplifier can condition low-level sensor outputs without the higher standing current associated with many precision analog stages. Low power does not eliminate the need for careful layout: place bypass capacitors near the supply pins, keep the RG connection short, and avoid high-leakage PCB contamination when the source impedance is high.
Được đề xuất
Current Shunt Measurement
The INA118PB can measure small voltage drops across current-shunt resistors while rejecting the supply or bus voltage appearing in common with the signal. Its 50 uV maximum offset and 110 dB minimum common-mode rejection at a gain of 1000 are valuable when the shunt voltage is only a few millivolts. The input-protection capability extends to ±40 V, adding robustness in systems where the shunt node may experience transients. However, the common-mode and output voltage must remain within operating limits, and Kelvin connections should be used to avoid including copper-drop resistance.
Được đề xuất
Medical Signal Conditioning
The INA118PB can serve as the analog front end for low-level biomedical sensor signals when high common-mode rejection, low offset, and low bias current are priorities. The three-op-amp instrumentation-amplifier architecture simplifies differential acquisition while the 350 uA quiescent current supports portable equipment. Input bias current of no more than 5 nA reduces errors with high-impedance bioelectrodes or resistive sensors, although application-specific leakage, isolation, patient safety, and regulatory requirements remain outside the device datasheet. A complete medical design should also address electrode protection, grounding, leakage current, and applicable safety standards.
Được đề xuất
Industrial Process Monitoring
The INA118PB is suitable for industrial process monitoring when transducers produce small differential signals over a larger common-mode voltage. Its 70 kHz bandwidth at a gain of 100 supports many sensor-monitoring bandwidths, while the maximum input protection of ±40 V improves tolerance to wiring faults. The device operates across -40°C to +85°C, making it appropriate for industrial temperature environments within that specified range. Designers should provide filtering for sensor bandwidth, maintain clean differential routing, and verify that ground and supply arrangements do not compromise the input common-mode range.
Được đề xuất
Precision Sensor and Transducer Interface
The INA118PB provides a compact analog interface for resistive, piezoelectric, and low-voltage transducer outputs where accurate differential amplification is required. The maximum input bias current of 5 nA limits loading errors in high-impedance circuits, and the 1 to 10,000 gain range allows the same family to cover multiple sensor sensitivities. A single external gain resistor simplifies adjustment, but its tolerance and temperature coefficient directly influence overall gain accuracy. Keep the gain resistor close to the RG pins, use a stable reference configuration, and verify bandwidth at the selected gain because the available 70 kHz value is specified at gain 100.
Được đề xuất
Dữ liệu tham khảo kỹ thuật cho INA118PB — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | INA118P | INA126P | INA128P | INA120P | INA149P |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | PDIP-8 | PDIP-8 | PDIP-8 | PDIP-8 | PDIP-8 | PDIP-8 |
| Product Type | Precision instrumentation amplifier | Instrumentation amplifier | Instrumentation amplifier | Instrumentation amplifier | Instrumentation amplifier | Instrumentation amplifier |
Bảo phân biệt quan trọng
- Low offset for precision differential measurements (vsINA118P)
- Low-power operation supports portable acquisition (vsINA118P)
- Protected inputs improve transient tolerance (vsINA118P)
- Verified high-gain common-mode rejection (vsINA118P)
Ghi chú thiết kế
Route IN+ and IN− as a short, symmetric differential pair and connect the external gain-setting resistor directly between the two RG terminals. Excess trace resistance, thermal gradients, and leakage can create errors that become significant at high gain. Keep the gain resistor close to the device, use a suitable reference connection, and avoid placing noisy switching or digital return currents beneath the sensitive input traces.
Place the supply bypass capacitors close to the VS and V− pins and provide the capacitance required by the manufacturer datasheet. The INA118PB is specified for operation from 1.35 V to 18 V and at dual supplies as low as ±2.25 V, but rail sequencing and output behavior still require validation. Do not interpret the ±40 V input-protection rating as permission to exceed the permitted supply voltage.
Do not select the gain solely from the sensor's full-scale voltage. Include offset, drift, input bias current, common-mode range, output swing, and bandwidth. The specified 70 kHz bandwidth applies at gain 100, so operation at gain 1 or 10,000 requires checking the manufacturer performance curves. Also verify that input filtering does not create excessive phase shift or interact with the protected input network.
Thông tin tuân thủ
The supplied verified results do not explicitly state RoHS, REACH, lead-free, halogen-free, or conflict-minerals status for INA118PB. AEC-Q100 is not applicable because the product is not identified as an automotive-qualified device.
