OPA735AIDR - Zero-Drift 1.6MHz CMOS Op Amp, 5uV | TI
MPN: OPA735AIDR ✓ Hoạt độngOPA735AIDR Tóm tắt
A zero-drift operational amplifier is a precision analog amplifier that uses internal calibration (chopping or auto-zeroing) to continuously correct its input offset voltage, eliminating the 1/f noise and temperature drift that limit conventional CMOS op amps. Within the signal-chain hierarchy, zero-drift op amps belong to the precision-amplifier (or instrumentation-amplifier) category, which sits under the broader amplifier IC family and ultimately under analog signal conditioning. The OPA735's 5 uV max VOS and 0.05 uV/degC drift place it in the sub-10 uV precision tier favored for transducer front-ends.
Key differentiating specifications include 5 uV maximum input offset voltage, 0.05 uV/degC maximum offset drift, 1.6 MHz GBW, 115 dB CMRR, 1.6 mA typical quiescent current, and 50 mV rail-to-rail output headroom. The device supports both single and bipolar supplies (e.g., +5 V, +/-2.5 V, +/-5 V) and provides high-impedance CMOS inputs that draw only a few picoamperes of bias current - critical for high-impedance sensor bridges.
Architecturally, the OPA735 uses a switched-capacitor auto-zero topology that periodically samples and cancels the input offset and 1/f noise, achieving drift performance comparable to much larger chopper-stabilized modules while drawing only milliamps of quiescent current. This makes it ideal for battery-powered precision instrumentation where both accuracy and power budget matter.
Typical applications include precision weigh scales, strain-gauge bridges, thermocouple conditioning, medical instrumentation front-ends, handheld multimeter ADC drivers, and precision current-sense amplifiers. Designers also deploy the OPA735 in active filters, integrators, and reference buffers for 16- to 24-bit ADCs.
When laying out the PCB, place the 0.1 uF power-supply bypass capacitor within 2 mm of the supply pin and keep input traces short and guarded to preserve the 115 dB CMRR at high frequencies. The SOIC-8 thermal performance is adequate for the device's low dissipation; no heatsink is required.
This page synthesizes distributor pricing, drop-in pin-compatible alternatives (including the OPA734 companion and cross-brand equivalents), and practical layout notes not found in the standalone datasheet.
Bộ thay thế dễ dàng lắp đặt cho OPA735AIDR — 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 OPA735AIDR (cùng hình factor và footprint) — khác nhau ở Package, Number of Channels, Amplifier Type, Gain-Bandwidth Product, Input Offset Voltage (max).
OPA735AID
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
OPA735AIDRG4
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
OPA734AIDR
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
OPA2277UA
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MCP6072T-E/SN
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MAX9100EUK+T
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →OPA735AIDR Tỷ lệ tối đa & tính chất điện
| Number of Channels | 1 |
| Amplifier Type | Zero-Drift / Auto-Zero CMOS Operational Amplifier |
| Input Offset Voltage (max) | 5 uV |
| Offset Drift (max) | 0.05 uV/degC |
| Gain-Bandwidth Product | 1.6 MHz |
| CMRR | 115 dB |
| Quiescent Current (typ) | 1.6 mA |
| Supply Voltage Range (single) | 2.7 V to 12 V |
| Supply Voltage Range (bipolar) | +/-1.35 V to +/-6 V |
| Output Swing | Rail-to-Rail (within 50 mV of rails) |
| Nhiệt độ hoạt động | -40 C to +85 C |
| Hộp | SOIC-8 (D) 3.90 mm |
| Kiểu lắp đặt | Surface Mount |
| Cấp MSL | 2 (1 year) |
| Trạng thái RoHS | Compliant |
| Input Type | CMOS, high-impedance |
Cấu hình chân OPA735AIDR
| Chân 1 | NC — Not connected (per datasheet) |
| Chân 2 | IN- — Inverting input |
| Chân 3 | IN+ — Non-inverting input |
| Chân 4 | V- — Negative supply |
| Chân 5 | NC — Not connected (per datasheet) |
| Chân 6 | OUT — Output |
| Chân 7 | V+ — Positive supply |
| Chân 8 | NC — Not connected (per datasheet) |
Ứng dụng tiêu biểu
OPA735AIDR phù hợp cho 7 Áp dụngs: Precision Weigh Scale Signal Conditioning, Thermocouple Cold-Junction Compensation, Handheld Multimeter ADC Driver, Medical Instrumentation Front-End, Precision Current-Sense Amplifier, Active Filter and Integrator Stage, Photodiode Transimpedance Amplifier.
Precision Weigh Scale Signal Conditioning
The OPA735AIDR is ideal for strain-gauge bridge amplification in weigh-scale front-ends. Its 5 uV max input offset and 0.05 uV/degC drift directly minimize scale zero-point error and creep over temperature, while the 115 dB CMRR rejects common-mode noise from the bridge excitation. The high-impedance CMOS inputs accept low-output-impedance bridges without loading distortion. A typical circuit places the OPA735 as the first-stage instrumentation amp (INA129) gain-of-100 block, feeding a 24-bit ADC. Compared to chopper op amps in this role, the OPA735's 1.6 MHz GBW handles fast settling for multi-conversion-per-second update rates common in shipping scales.
Được đề xuất
Thermocouple Cold-Junction Compensation
The OPA735AIDR serves as a precision buffer for thermocouple cold-junction compensation in industrial temperature monitoring. The 5 uV offset translates to <0.1 C equivalent error for Type K thermocouples, and the 0.05 uV/degC drift stays below the measurement resolution of typical 16-bit ADCs across the industrial -40 C to +85 C ambient range. The rail-to-rail output swing supports single 5 V supply designs, eliminating the negative rail typically required for thermocouple conditioning. Combined with a precision reference (REF3030) and an op-amp thermocouple amplifier (OPA2188), the OPA735 enables total error budgets under 0.5 C.
Được đề xuất
Handheld Multimeter ADC Driver
The OPA735AIDR drives the input of 16- to 20-bit ADCs in handheld digital multimeters. Its 1.6 MHz GBW settles quickly enough for the 4 kHz conversion rate typical of RMS multimeters, while the 5 uV max offset contributes less than 1 count at 20-bit resolution on a 5 V reference. The single-supply 2.7 V to 12 V operation supports both 3.3 V logic-level ADCs and 5 V bipolar-input ADCs without level translation. Compared to OPA2277 in this role, the OPA735's auto-zero drift cancellation eliminates the periodic recalibration that conventional precision op amps require for 0.01% accuracy DMMs.
Được đề xuất
Medical Instrumentation Front-End
The OPA735AIDR is well-suited to the front-end of medical instrumentation including ECG, EEG, and pulse-oximeter signal chains. The 5 uV offset and 0.05 uV/degC drift maintain baseline stability over long patient-monitoring sessions, while the high input impedance (CMOS, pA-level bias) prevents loading of skin-electrode biopotential sources. The rail-to-rail output swing on a single 5 V supply enables direct connection to 24-bit medical-grade ADCs. The device's low 1.6 mA quiescent current is critical for battery-powered ambulatory monitors. FDA-cleared designs reference the OPA735 family in the documented schematics.
Được đề xuất
Precision Current-Sense Amplifier
The OPA735AIDR implements high-side or low-side current-sense amplifiers in battery-management and power-monitoring applications. Its 5 uV offset translates to sub-mA current-measurement accuracy when used with a 10 mOhm shunt, and the rail-to-rail output swing supports both low-voltage (3.3 V) and high-voltage (12 V) supply rails. The 1.6 MHz GBW handles the dynamic response of switching-mode power supplies, while the 115 dB CMRR rejects switching noise injected onto the common-mode voltage. Combined with a precision reference (REF3012) and 16-bit ADC (ADS1115), the OPA735 enables coulomb-counting accuracy within 1% across the discharge curve.
Được đề xuất
Active Filter and Integrator Stage
The OPA735AIDR functions as a precision active filter or integrator in 50 Hz/60 Hz line-noise rejection stages, sensor-signal conditioners, and analog computing modules. The 1.6 MHz GBW supports second-order low-pass filters with cutoffs up to 50 kHz, while the 5 uV offset and 0.05 uV/degC drift preserve DC accuracy in integrator reset circuits. The SOIC-8 single-channel package allows dense PCB layouts for multi-pole filters. Compared to TL082-class op amps, the OPA735's drift performance reduces long-time-constant integrator error to negligible levels in 10-second time-base integrators.
Được đề xuất
Photodiode Transimpedance Amplifier
The OPA735AIDR operates as a transimpedance amplifier (TIA) for photodiode current measurement in optical sensors, smoke detectors, and ambient-light systems. The high-impedance CMOS inputs handle pA-level photodiode currents directly without introducing bias-current error, while the 5 uV offset and low drift enable accurate measurements down to nA-scale photocurrents. The 1.6 MHz GBW supports gain-bandwidth products adequate for 100 kHz pulse response in optical-communication receivers. Combined with a low-leakage photodiode (BPW34) and 16-bit ADC, the OPA735 enables precision light-measurement systems.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho OPA735AIDR — 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 | OPA735AID | OPA735AIDRG4 | OPA734AIDR | OPA2277UA | MCP6072T-E/SN |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Microchip Technology |
| Package | SOIC-8 (D) | SOIC-8 (D) - same | SOIC-8 (D) - same | SOIC-8 (D) - same | SOIC-8 (D) - same | SOIC-8 (SN) - same footprint |
| Gain-Bandwidth Product | 1.6 MHz | 1.6 MHz | 1.6 MHz | 0.7 MHz (-56%) | 1 MHz (-38%) | 1.2 MHz (-25%) |
| Input Offset Voltage (max) | 5 uV | 5 uV | 5 uV | 5 uV | 10 uV (+100%) | 150 uV (+2900%) |
| Offset Drift (max) | 0.05 uV/degC | 0.05 uV/degC | 0.05 uV/degC | 0.05 uV/degC | 0.1 uV/degC (+100%) | 1.5 uV/degC (+2900%) |
| Quiescent Current (typ) | 1.6 mA | 1.6 mA | 1.6 mA | 0.6 mA (-62%) | 1.4 mA (-12%) | 1.1 mA (-31%) |
| CMRR | 115 dB | 115 dB | 115 dB | 115 dB | 130 dB (+15 dB) | 90 dB (-25 dB) |
| Supply Voltage Range | 2.7 V to 12 V | 2.7 V to 12 V | 2.7 V to 12 V | 2.7 V to 12 V | +/-2 V to +/-18 V | 1.8 V to 5.5 V |
| Rail-to-Rail Output | Yes (within 50 mV) | Yes | Yes | Yes | No (swing to +/-13 V) | Yes (RRIO) |
Bảo phân biệt quan trọng
- Sub-10 uV zero-drift precision in SOIC-8 (vsOPA2277UA)
- Higher GBW for wider signal bandwidth (vsOPA734AIDR)
- Best-in-class CMRR for sensor bridge applications (vsMCP6072T-E/SN)
Ghi chú thiết kế
Place a 0.1 uF ceramic bypass capacitor within 2 mm of the V+ pin and a 1 uF to 10 uF bulk capacitor at the supply entry point. The SOIC-8 package pin layout places V- at pin 4 - do not route the negative-rail input trace under the package to avoid coupling noise into the high-impedance CMOS inputs. Use a ground plane on the layer beneath the op amp to maintain the 115 dB CMRR at high frequencies.
The OPA735 does not have rail-to-rail inputs - the common-mode voltage range extends only to within 1.5 V of V-. Exceeding this range distorts the input stage and can introduce permanent damage. For input signals approaching V-, use the OPA2277UA or MCP6072T-E/SN instead. Auto-zero amplifiers also generate small clock-feedthrough spurs at the switching frequency; avoid using the OPA735 in audio-frequency signal paths where these spurs are audible.
At unity gain, the 1.6 MHz GBW supports signal bandwidth up to ~160 kHz with 12 dB of headroom. For higher-frequency signals or sharper anti-alias filters, use a faster op amp such as the OPA354 (250 MHz). When driving capacitive loads above 100 pF, add a 50 ohm series resistor at the output to maintain phase margin; the OPA735 is stable for capacitive loads up to 1 nF without compensation.
Thông tin tuân thủ
RoHS and REACH compliant per TI product page. Not AEC-Q100 qualified; for automotive applications verify with TI. Halogen-free status not explicitly stated in the available data.
