OPA4140 - Quad 11MHz Low-Noise JFET Precision Op Amp | Texas Instruments
부품 번호: OPA4140 ✓ 활성| 수량 | 단가 | 합계 |
|---|---|---|
| 1 | $7.95 | $7.95 |
| 10 | $7.16 | $71.60 |
| 100 | $6.37 | $637.00 |
| 500 | $5.74 | $2,870.00 |
| 1,000 | $5.1 | $5,100.00 |
| 3,000 | $4.42 | $13,260.00 |
OPA4140 개요
An operational amplifier (op amp) is an active analog building block that amplifies the difference between two input voltages and drives the result through an output stage. The op-amp hierarchy sits within analog ICs, then linear ICs, then signal-conditioning and power-management ICs. JFET-input op amps form a sub-family that uses a junction field-effect transistor at the differential input pair, giving extremely low input bias current and high input impedance - critical for photodiode, pH-electrode, and high-impedance transducer front-ends that bipolar input stages cannot load correctly.
Key features include 0.5 pA input bias current, 0.5 mV maximum input offset voltage (A-grade), unity-gain stability, output swing to within 50 mV of either rail at 10 kΩ load, and short-circuit protection (rated ±18 mA). The device operates across -40 °C to +125 °C and is unity-gain stable for purely resistive or moderate-capacitive loads, eliminating the need for external compensation.
Architecturally, the OPA4140 combines a JFET input differential pair with a bipolar second stage and a rail-to-rail class AB output stage. This hybrid topology achieves the low bias current of JFET, the low noise and precision of bipolar, and the wide output swing that lets a single 5 V rail power ADC drivers and reference buffers without external level shifters.
Typical applications include precision analog front-ends (weigh scales, strain gauges, temperature loggers), battery-powered instrumentation, photodiode transimpedance amplifiers, and active filters or integrators in test equipment. Designers choose the OPA4140 over bipolar alternatives when the source impedance exceeds 10 kΩ.
When routing the PCB, place 0.1 µF ceramic bypass capacitors within 5 mm of each supply pin and keep input traces short to preserve the 5.1 nV/√Hz noise floor. Use a ground plane under the package to shield inputs from digital noise, and respect the input common-mode range that extends to the negative rail.
This page synthesizes distributor pricing, drop-in same-family alternatives, and practical design notes that complement the manufacturer datasheet.
드롭인 대체품: OPA4140 — 동일 패키지, 핀 호환. PCB 재작업이 필요한 다른 패키지 부품은 제외됩니다.
빠른 비교 도구 — 나란히 비교할 대체 부품을 선택하십시오:
OPA4140AIPWR
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
OPA4140AIDR
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
OPA4140AIPWRQ1
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
OPA4140IPWR
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
OPA4141AIPW
✅ 드롭인📋 참조 대체품 (카탈로그에 없음)
OPA4140 최대 정격 & 전기적 특성
| Number of Channels | 4 (Quad) |
| Gain-Bandwidth Product (GBW) | 11 MHz |
| Slew Rate | 20 V/µs |
| Input Voltage Noise Density | 5.1 nV/√Hz |
| Input Bias Current (Ib) | 0.5 pA (typ), 10 pA (max) |
| Input Offset Voltage (Vos) | ±0.5 mV max (A-grade); ±1.5 mV max (standard) |
| Input Offset Voltage Drift (dVos/dT) | ±1.5 µV/°C |
| Supply Voltage Range (Single) | 4.5 V to 36 V |
| Supply Voltage Range (Dual) | ±2.25 V to ±18 V |
| Quiescent Current per Channel | 1.8 mA (typ) |
| Output Swing | Rail-to-rail (within 50 mV at 10 kΩ) |
| Output Short-Circuit Current | ±18 mA |
| Common-Mode Input Range | V- to (V+ - 1.5 V) |
| 동작 온도 범위 | -40 °C to +125 °C |
| Package Options | 14-pin SOIC (D), 14-pin TSSOP (PW) |
| RoHS 상태 | Compliant |
| Unity-Gain Stable | Yes |
OPA4140 핀 구성
| 핀 1 | 1OUT — Channel 1 op amp output |
| 핀 2 | 1IN- — Channel 1 inverting input |
| 핀 3 | 1IN+ — Channel 1 non-inverting input |
| 핀 4 | V+ — Positive supply voltage |
| 핀 5 | 2IN+ — Channel 2 non-inverting input |
| 핀 6 | 2IN- — Channel 2 inverting input |
| 핀 7 | 2OUT — Channel 2 op amp output |
| 핀 8 | 3OUT — Channel 3 op amp output |
| 핀 9 | 3IN- — Channel 3 inverting input |
| 핀 10 | 3IN+ — Channel 3 non-inverting input |
| 핀 11 | V- — Negative supply voltage (or GND for single supply) |
| 핀 12 | 4IN+ — Channel 4 non-inverting input |
| 핀 13 | 4IN- — Channel 4 inverting input |
| 핀 14 | 4OUT — Channel 4 op amp output |
일반적인 애플리케이션
OPA4140 적합 용도: 6 애플리케이션s: Precision Sensor Signal Conditioning, Photodiode Transimpedance Amplifier, Industrial Process Control Analog Input, Active Filters and Integrators, Battery-Powered Instrumentation, Test and Measurement Equipment.
Precision Sensor Signal Conditioning
The OPA4140's 0.5 pA JFET input bias current and 5.1 nV/√Hz input noise make it ideal for precision sensor signal conditioning in weighing scales, strain-gauge bridges, and thermocouple amplifiers. With 0.5 mV max Vos (A-grade), it adds negligible error to a Wheatstone bridge output, and the rail-to-rail output swing lets a single 5 V rail drive a 16-bit ADC at full scale. Place the OPA4140 directly adjacent to the sensor to minimize leakage-induced errors and use a driven guard ring around high-impedance inputs.
추천
Photodiode Transimpedance Amplifier
For photodiode transimpedance amplifiers (TIA) in optical sensing, the OPA4140's JFET input provides sub-picoampere input bias that does not compete with photodiode dark current in the nA range. Combined with 11 MHz GBW and 20 V/µs slew rate, it supports TIA bandwidths beyond 1 MHz at 100 kΩ gains for pulse oximetry and LiDAR receivers. The 4.5 V to 36 V supply range also makes it suitable for APD bias networks that require elevated reverse bias on the photodiode.
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Industrial Process Control Analog Input
In industrial process-control analog input modules, the OPA4140 provides four precision op amps per TSSOP-14 - enough for a complete 4-20 mA loop conditioner, RTD bridge excitation, level-shift buffer, and ADC driver on a single IC. Operating from ±15 V or 24 V industrial supplies, it tolerates common-mode voltages near the negative rail. Combined with a 24-bit delta-sigma ADC, the OPA4140's 5.1 nV/√Hz noise floor sets system dynamic range beyond 100 dB for PLC analog input cards.
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Active Filters and Integrators
The OPA4140's unity-gain stability, 11 MHz GBW, and 20 V/µs slew rate suit active filter and integrator designs in audio crossovers, lock-in amplifiers, and servo-loop compensators. The four channels per package enable a 4th-order Sallen-Key filter or dual integrator/dual summer network on one IC, reducing PCB area and channel-to-channel gain-match error to within 0.5 dB. Rail-to-rail output then allows single 9 V or 12 V supply operation without losing dynamic range.
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Battery-Powered Instrumentation
For battery-powered instruments like handheld multimeters and portable medical monitors, the OPA4140's 1.8 mA per-channel quiescent current and 4.5 V minimum supply support 2-cell battery stacks down to 5 V. The JFET input prevents current loading on the battery monitor shunt, and the rail-to-rail output drives the LCD bias generator or audio buzzer directly. Sleep current can be further reduced by powering the OPA4140 from a TPS7A02 LDO that the microcontroller can switch off in standby.
추천
Test and Measurement Equipment
In test-and-measurement equipment such as bench multimeters, data loggers, and oscilloscope front-end buffers, the OPA4140 provides four matched channels for differential probes, programmable gain stages, and reference buffers. Its 5.1 nV/√Hz noise keeps the instrument's noise floor below the LSB of a 20-bit ADC at 1 kHz bandwidth, while unity-gain stability allows direct use as an output buffer on a DAC-driven precision stimulus generator. The -40 °C to +125 °C rating also supports outdoor or industrial-environment test racks.
추천
추천 제품 요약
엔지니어링 참조 데이터: OPA4140 — 비교, 설계 지침 및 규정 준수 정보.
선택 가이드
대체품과의 비교
| 파라미터 | 이 제품 | OPA4140AIPWR | OPA4140AIDR | OPA4140AIPWRQ1 | OPA4140IPWR | OPA4141AIPW |
|---|---|---|---|---|---|---|
| Package | TSSOP-14 (PW) | TSSOP-14 (PW) - same | SOIC-14 (D) | TSSOP-14 (PW) - same | TSSOP-14 (PW) - same | TSSOP-14 (PW) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Channels | 4 (Quad) | 4 (Quad) | 4 (Quad) | 4 (Quad) | 4 (Quad) | 4 (Quad) |
| Input Voltage Noise Density | 5.1 nV/√Hz | 5.1 nV/√Hz | 5.1 nV/√Hz | 5.1 nV/√Hz | 5.1 nV/√Hz | 3.5 nV/√Hz (-31%) |
| Maximum Input Offset Voltage (A-grade) | ±0.5 mV | ±0.5 mV | ±0.5 mV | ±0.5 mV | ±1.5 mV (standard grade, no A-suffix) | ±0.12 mV (-76%) |
| Automotive Grade (AEC-Q100) | No | No | No | Yes (AEC-Q100) | No | No |
주요 차별점
- JFET input with sub-pA bias current vs bipolar alternatives (vs OPA2277 (bipolar, 1 nA Ib typical))
- Rail-to-rail output swing vs traditional precision amps (vs OPA277 (no rail-to-rail, swings to within 1.5 V of rails))
- Automotive-grade TSSOP-14 option with same die (vs Standard-grade OPA4140AIPWR (no AEC-Q100 PPAP))
설계 노트
Place a 0.1 µF X7R ceramic bypass capacitor within 5 mm of each supply pin (V+ pin 4 and V- pin 11), and add a 10 µF bulk electrolytic on each supply rail to handle load transients on the rail-to-rail output stage. Keep the input traces short and guarded with a ground plane to preserve the 5.1 nV/√Hz input noise floor; every 5 mm of unshielded high-impedance trace can pickup tens of microvolts of 50/60 Hz interference. For high-impedance (>1 MΩ) inputs, surround the trace with a driven guard ring biased to the input common-mode voltage to prevent leakage from contamination.
Estimated: at 25 °C ambient and 1.8 mA quiescent per channel on a 12 V supply, each channel dissipates 21.6 mW (four channels total ≈ 86.4 mW). The TSSOP-14 has theta-JA of 120 °C/W, giving a junction temperature rise of about 10 °C above ambient - well below the 150 °C limit. However, when driving a short-circuit output (±18 mA), dissipation per channel can spike beyond 200 mW, so avoid sustained short-circuit conditions and respect the absolute-maximum junction temperature.
Do not apply input voltages above (V+ - 1.5 V); although the JFET input tolerates high voltages with body clamps, exceeding the positive rail can permanently damage the input stage because the OPA4140 is NOT an RRIO (rail-to-rail input) part. Also, the -IN input of each channel sits within the package under the channel's +IN pin - swapping their PCB nets reverses the op amp polarity. Finally, do not assume 'A-suffix' is required; the standard-grade OPA4140 (±1.5 mV Vos) is fine for many designs and saves cost when the offset error can be calibrated in software.
규정 준수 정보
RoHS compliant per TI product page. Lead-free and halogen-free confirmed in datasheet materials disclosure section. AEC-Q100 not applicable for standard OPA4140AIPWR - choose the -Q1 suffix variant (OPA4140AIPWRQ1) for automotive AEC-Q100 qualified supply. REACH compliance status per EU REACH SVHC declaration available on ti.com.
