INA129U/2K5 - Precision Low Power INA, SOIC-8 | Texas Instruments
MPN: INA129U/2K5 ✓ فعالINA129U/2K5 جائزہ
An instrumentation amplifier is a precision differential amplifier with very high input impedance on both inputs, a defined and stable gain set by one external resistor, and exceptionally high common-mode rejection. The INA belongs to the family of analog front-end ICs that sit between a sensor (bridge, thermocouple, biopotential electrode) and an ADC. The category hierarchy is: instrumentation amplifier -> differential amplifier -> operational amplifier -> analog IC -> semiconductor. The three-op-amp topology isolates the input signal from the gain-setting resistor network, allowing tiny differential signals (often microvolts) to be amplified cleanly in noisy industrial environments.
Key features of the INA129U/2K5 include wideband operation up to 1.3 MHz (G = 1) with 200 kHz bandwidth even at G = 100, a 4 V/µs slew rate, ±2.25 V to ±18 V dual-supply operation (±2.25 V minimum; typically ±15 V in transducer systems), input protection to ±40 V, and a quiescent current of only 700 µA typical. The exposed SO-8 package simplifies reflow assembly on standard 8-pin SOIC land patterns identical to the INA128, AD620, and other pin-compatible INAs.
The current-feedback input stage keeps bandwidth flat across the full gain range, an advantage over voltage-feedback INAs that lose bandwidth at high gain. The INA129's gain equation G = 1 + 49.4kΩ/RG matches the AD620, allowing direct drop-in migration from legacy designs. The combination of low noise, low drift, and high CMRR makes the INA129U/2K5 well-suited for strain-gauge bridges, weigh scales, thermocouple amplifiers, medical instrumentation (ECG/EEG front-ends), and industrial process-control analog inputs.
Typical applications include weigh scales and load-cell signal conditioning, ECG and biomedical front-ends, thermocouple and RTD pre-amplification, and industrial 4-20 mA loop readouts. Place the gain-setting resistor close to pins 1 and 8, and use 0.1 µF ceramic bypass capacitors on both supply pins to preserve the 120 dB CMRR across frequency. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
کے لیے ڈراپ اِن متبادل INA129U/2K5 — یکساں پیکیج، پن سے پن مطابقت پذیر۔ مختلف پیکیج والے پرزے جن کے لیے PCB دوبارہ کام درکار ہو، شامل نہیں ہیں۔
اس سیریز میں مختلف ورژن
اسی سیریز کے ماڈلز جو ڈراپ اِن مطابقت رکھتے ہیں INA129U/2K5 (یکساں فارم فیکٹر اور فٹ پرنٹ) — میں مختلف Product Type, Package, Gain Range, Mounting Type, Architecture.
INA128U/2K5
✅ ڈراپ-اِن📋 حوالہ جاتی متبادل (کیٹلاگ میں نہیں)
INA128UA/2K5
✅ ڈراپ-اِن📋 حوالہ جاتی متبادل (کیٹلاگ میں نہیں)
INA121UAG4
✅ ڈراپ-اِن📋 حوالہ جاتی متبادل (کیٹلاگ میں نہیں)
AD620ANZ
✅ ڈراپ-اِنقیمت کے لیے رابطہ کریں
ڈیٹا شیٹ دیکھیں →INA333AIDR
✅ ڈراپ-اِن ⚠️ تفصیلات غیر تصدیق شدہ📋 حوالہ جاتی متبادل (کیٹلاگ میں نہیں)
INA118PB
✅ ڈراپ-اِن ⚠️ تفصیلات غیر تصدیق شدہقیمت کے لیے رابطہ کریں
ڈیٹا شیٹ دیکھیں →INA129U/2K5 زیادہ سے زیادہ ریٹنگز اور برقی خصوصیات
| Manufacturer | Texas Instruments |
| Product Type | Instrumentation Amplifier (INA) |
| Series | INA12x (INA128 / INA129) |
| Number of Channels | 1 |
| ٹوپولوجی | 3-Op-Amp, current-feedback input |
| پیکیج / کیس | 8-pin SOIC (SO-8) |
| ماؤنٹنگ ٹائپ | Surface Mount |
| Supply Voltage (Dual) | ±2.25 V to ±18 V |
| کوئیسینٹ کرنٹ | 700 µA typical |
| Input Offset Voltage (max) | 50 µV |
| Offset Drift (max) | 0.5 µV/°C |
| Input Bias Current (max) | 5 nA |
| CMRR (min) | 120 dB (at G = 100) |
| Bandwidth (G = 1) | 1.3 MHz |
| Bandwidth (G = 100) | 200 kHz |
| Slew Rate | 4 V/µs |
| Gain Range | 1 V/V to 10,000 V/V |
| Gain Equation | G = 1 + 49.4kΩ / RG (AD620-compatible) |
| Input Protection | ±40 V |
| آپریٹنگ درجہ حرارت | -40 °C to +85 °C |
| Reel Quantity | 2,500 (per /2K5 suffix) |
| RoHS | Compliant |
INA129U/2K5 پن کنفیگریشن
| پن 1 | RG — Gain-setting resistor pin (connect external resistor to pin 8) |
| پن 2 | -IN — Inverting input |
| پن 3 | +IN — Non-inverting input |
| پن 4 | V- — Negative supply voltage |
| پن 5 | REF — Output reference (level-shift output; normally tied to GND for dual supply) |
| پن 6 | OUTPUT — Amplifier output |
| پن 7 | V+ — Positive supply voltage |
| پن 8 | RG — Gain-setting resistor pin (connect external resistor to pin 1) |
عام استعمالات
INA129U/2K5 کے لیے موزوں ہے 6 ایپلیکیشنs: Weigh Scale / Load Cell Signal Conditioning, ECG and Biomedical Front-End, Thermocouple and RTD Temperature Amplifier, Industrial 4-20 mA Loop Readout, Strain-Gauge Bridge Amplifier, Audio Precision Preamplifier.
Weigh Scale / Load Cell Signal Conditioning
The INA129U/2K5 is the canonical load-cell amplifier for industrial weigh scales. Its 120 dB minimum CMRR at G=100 rejects 50/60 Hz mains pickup that couples into long load-cell cables, while the 50 µV maximum offset and 0.5 µV/°C maximum drift maintain calibration accuracy across the -40 °C to +85 °C industrial range. The current-feedback input stage keeps bandwidth flat (~200 kHz) even at G=100, allowing fast settling for batch-weighing applications. Place the gain resistor close to pins 1 and 8 and add 0.1 µF ceramic bypass on both supply rails to preserve the 120 dB CMRR figure. The SOIC-8 footprint is pin-compatible with AD620, enabling direct migration.
تجویز کردہ
ECG and Biomedical Front-End
The INA129U/2K5 is widely used as the first gain stage in ECG, EEG, and EMG front-ends. Its 5 nA maximum input bias current is well below typical skin-electrode impedance levels, preventing polarization of Ag/AgCl electrodes. The 120 dB minimum CMRR rejects common-mode mains interference when set to G = 10 with right-leg-drive feedback, while the 50 µV maximum offset contributes negligible baseline wander. The 1.3 MHz bandwidth captures high-frequency QRS complexes without distortion. Designers should add ESD protection (TVS arrays) and AC coupling at the inputs per AAMI EC11/IEC 60601-1 safety standards. The SOIC-8 footprint supports compact wearable designs.
تجویز کردہ
Thermocouple and RTD Temperature Amplifier
The INA129U/2K5 amplifies the microvolt-level outputs of K-type, J-type, and S-type thermocouples with 50 µV offset accuracy that adds less than 1 °C error to cold-junction-compensated readings. The high CMRR rejects 50/60 Hz thermocouple-loop pickup in industrial furnaces. For RTD-based temperature sensing, the INA129's 5 nA bias current minimizes self-heating errors on PT100/PT1000 elements. The ±2.25 V to ±18 V supply range allows operation from standard ±5 V or ±15 V industrial rails. Use the REF pin (pin 5) to level-shift the output for single-supply ADC interfaces; the gain equation G = 1 + 49.4kΩ/RG simplifies resistor selection for the 1 mV/°C K-type output range.
تجویز کردہ
Industrial 4-20 mA Loop Readout
The INA129U/2K5 reads the differential voltage across a current-sense resistor in 4-20 mA HART-protocol loops. Its ±40 V input protection survives field wiring faults and accidental mains contact, critical for IEC 61000-4 compatibility in process-control installations. The 120 dB CMRR rejects ground-loop noise between field transmitters and the control cabinet, while the 1.3 MHz bandwidth supports HART 1200 bps FSK modulation pass-through without attenuation. The SOIC-8 small footprint enables channel-density multi-rail acquisition cards. Power the INA129 from the same ±15 V supply that powers downstream ADCs, simplifying the BOM.
تجویز کردہ
Strain-Gauge Bridge Amplifier
The INA129U/2K5 is ideal for amplifying full-bridge and half-bridge strain-gauge transducers in structural-health monitoring and pressure-sensor applications. The 120 dB CMRR ensures bridge common-mode voltage (typically 2.5 V or 5 V) is rejected to better than 1 µV, while the 50 µV offset does not compromise the millivolt-level strain signals. The 4 V/µs slew rate preserves dynamic response for vibration and impact testing. The SOIC-8 footprint and external gain resistor allow precise gain calibration per transducer sensitivity (typically 1-4 mV/V). Place a 100 nF ceramic bypass on each supply pin and keep the gain resistor within 5 mm of pins 1 and 8 to maintain CMRR.
تجویز کردہ
Audio Precision Preamplifier
The INA129U/2K5 functions as a precision microphone preamp and line-level instrumentation preamp in professional audio equipment. The 1.3 MHz bandwidth and 4 V/µs slew rate support full 20 Hz-20 kHz audio bandwidth with low distortion. The 50 µV offset is inaudible in typical microphone gain (G = 100), and the 120 dB CMRR rejects ground-loop hum in balanced audio cable runs. The ±18 V maximum supply accommodates ±15 V professional audio rails. Use the REF pin to bias the output to mid-rail for single-supply ADC interfacing in digital mixers. Designers should add RF input filtering and ESD protection per IEC 61000-4-2 for stage-grade equipment.
تجویز کردہ
تجویز کردہ پروڈکٹس کا خلاصہ
کے لیے انجینئرنگ ریفرنس ڈیٹا INA129U/2K5 — موازنہ، ڈیزائن رہنمائی، اور تعمیل کی معلومات۔
انتخاب کی گائیڈ
متبادلات کے ساتھ موازنہ
| پیرامیٹر | یہ پروڈکٹ | INA128U/2K5 | INA128UA/2K5 | AD620ANZ | INA333AIDR |
|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Analog Devices | Texas Instruments |
| Package | SOIC-8 (narrow) | SOIC-8 (narrow) | SOIC-8 (Wide) | SOIC-8 (narrow) | MSOP-8 |
| Topology | 3-Op-Amp, current-feedback | 3-Op-Amp, current-feedback | 3-Op-Amp, current-feedback | 3-Op-Amp, current-feedback | 3-Op-Amp, zero-drift chopper |
| Input Offset Voltage (max) | 50 µV | 50 µV | 50 µV | 50 µV | 25 µV (typ) |
| CMRR (min) | 120 dB (G=100) | 120 dB (G=100) | 120 dB (G=100) | 100 dB (G=1-1000) | 100 dB |
| Bandwidth (G=100) | 200 kHz | 200 kHz | 200 kHz | 120 kHz | 3.5 kHz |
| Slew Rate | 4 V/µs | 4 V/µs | 4 V/µs | 1.2 V/µs | 0.16 V/µs |
| Supply Voltage (Dual) | ±2.25 V to ±18 V | ±2.25 V to ±18 V | ±2.25 V to ±18 V | ±2.3 V to ±18 V | +1.8 V to +5.5 V (single supply) |
| Gain Equation | G = 1 + 49.4kΩ/RG (AD620-compatible) | G = 1 + 50kΩ/RG (industry std) | G = 1 + 50kΩ/RG (industry std) | G = 1 + 49.4kΩ/RG (same) | G = 1 + 100kΩ/RG |
اہم امتیازی خصوصیات
- AD620-compatible gain equation for direct legacy migration (بمقابلہINA128U/2K5)
- Higher CMRR than AD620 for industrial noise environments (بمقابلہAD620ANZ)
- Current-feedback input stage maintains bandwidth at high gain (بمقابلہINA333AIDR (zero-drift))
ڈیزائن نوٹس
Place the gain-setting resistor RG within 5 mm of pins 1 and 8 to minimize parasitic capacitance that degrades CMRR at high frequencies. Use 0.1 µF ceramic bypass capacitors on both V+ (pin 7) and V- (pin 4), positioned within 3 mm of the supply pins. Route input traces as a matched differential pair with guard traces tied to REF potential (pin 5) to reduce common-mode pickup on long sensor cables.
The REF pin (pin 5) is the output common-mode reference and must be driven from a low-impedance source. For dual-supply operation, tie REF directly to ground. For single-supply operation, drive REF from a buffered mid-rail (e.g., a resistor divider with 10 µF bypass) to level-shift the output swing above ground. Driving REF with high impedance introduces common-mode noise and degrades the 120 dB CMRR figure.
Do not exceed the ±40 V input protection rating; in industrial installations, add external TVS diodes or spark gaps for IEC 61000-4-5 surge compliance. Do not connect input signals before power is applied - the input protection clamps can forward-bias and damage downstream circuitry. Use the correct gain-resistor package (typically 0805 or 0603) with 0.1% tolerance for gain accuracy; 1% resistors introduce 1% gain error that propagates to system calibration.
تعمیل کی معلومات
RoHS compliant per TI product page. Not AEC-Q100 qualified; for automotive applications consider INA129-Q1. Lead-free SOIC-8 package with NiPdAu lead finish.
