ADS8482IRGZR - 18-bit 1MSPS SAR ADC w/Internal Ref | TI
MPN: ADS8482IRGZR ✓ Hoạt độngADS8482IRGZR Tóm tắt
An SAR (Successive Approximation Register) ADC is a precision data-converter architecture that uses an internal binary-search algorithm against a precision DAC to resolve a single input sample per conversion cycle. SAR ADCs occupy the middle ground between slow, ultra-precise delta-sigma ADCs and fast but lower-resolution flash ADCs, and are widely used in industrial process control, instrumentation, and medical imaging where single-shot accuracy at moderate sample rates is required. The ADS8482 family sits in the power-management-and-conversion IC hierarchy: ADC -> data converter -> signal-chain IC -> mixed-signal semiconductor.
Key differentiating specifications include 1 MSPS guaranteed throughput, an internal low-drift 4.096 V reference that eliminates an external reference IC, true 18-bit no-missing-codes performance, 1 LSB (max) INL and DNL, pseudo-bipolar fully differential inputs accepting ±VREF, and a 48-pin VQFN PowerPAD that keeps theta_JA low enough for industrial operation without a heatsink. The wide digital-interface flexibility (18/16/8-bit) lets designers connect it directly to 8-bit microcontrollers, 16-bit DSPs, or 18-bit ASICs without external glue logic.
Architecturally, the ADS8482 combines a charge-redistribution SAR DAC, an on-chip precision bandgap reference, a differential input front end, and a digital interface engine that supports byte, word, and full-word readback. The pseudo-bipolar input accepts signals from -VREF to +VREF around mid-scale (2.048 V), which simplifies signal conditioning for many sensor-bridge and bipolar transducer outputs.
Typical applications include medical imaging front ends, industrial process-control data acquisition cards, precision weigh scales, optical sensor interfaces, and vibration analysis. The 1 MSPS throughput and 18-bit resolution make it a strong fit for multiplexed multi-channel systems where one ADC serves many slow sensors.
A primary design consideration is bypassing: the reference pin and AVDD rails each require a low-ESR ceramic plus bulk capacitor placed within a few millimeters of the package to achieve the datasheet SNR and DNL. Pseudo-bipolar inputs must be DC-biased to mid-scale via high-impedance resistor networks to avoid clipping on negative excursions.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the standalone manufacturer datasheet.
Bộ thay thế dễ dàng lắp đặt cho ADS8482IRGZR — 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 ADS8482IRGZR (cùng hình factor và footprint) — khác nhau ở Package, Data Interface, Operating Temperature, Architecture, Resolution.
ADS8482IBRGZR
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ADS8481IRGZR
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ADS8472IRGZR
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ADS8472IBRGZR
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →ADS8482IRGZR Tỷ lệ tối đa & tính chất điện
| Độ phân giải | 18 bit |
| Sample Rate | 1 MSPS |
| Architecture | SAR (Successive Approximation Register) |
| Input Channels | 1 differential (pseudo-bipolar) |
| Input Range | 0 V to 4.096 V (pseudo-bipolar, ±VREF) |
| Internal Reference Voltage | 4.096 V |
| Digital Interface | Parallel (18/16/8-bit selectable) |
| Supply Voltage (AVDD) | 5 V (typ) |
| Nhiệt độ hoạt động | -40C to +85C (industrial) |
| Hộp | 48-VQFN (RGZ) 7x7 mm with PowerPAD |
| Kiểu lắp đặt | Surface Mount |
| Trạng thái RoHS | Compliant |
| Lead-Free | Yes |
Cấu hình chân ADS8482IRGZR
| Chân 1 | AVDD — Analog supply voltage |
| Chân 2 | AGND — Analog ground |
| Chân 3 | REF — Reference voltage I/O (4.096 V internal) |
| Chân 4 | IN+ — Positive differential analog input |
| Chân 5 | IN- — Negative differential analog input |
| Chân 6 | AVDD — Analog supply voltage |
| Chân 7 | AGND — Analog ground |
| Chân 8 | CONVST — Conversion start input |
| Chân 9 | CS — Chip select input |
| Chân 10 | RD — Read input |
| Chân 11 | BUSY — Conversion busy output |
| Chân 12 | DB0 — Data bit 0 (LSB) |
| Chân 13 | DB1 — Data bit 1 |
| Chân 14 | DB2 — Data bit 2 |
| Chân 15 | DB3 — Data bit 3 |
| Chân 16 | DB4 — Data bit 4 |
| Chân 17 | DB5 — Data bit 5 |
| Chân 18 | DB6 — Data bit 6 |
| Chân 19 | DB7 — Data bit 7 |
| Chân 20 | DB8 — Data bit 8 |
| Chân 21 | DB9 — Data bit 9 |
| Chân 22 | DB10 — Data bit 10 |
| Chân 23 | DB11 — Data bit 11 |
| Chân 24 | DB12 — Data bit 12 |
| Chân 25 | DB13 — Data bit 13 |
| Chân 26 | DB14 — Data bit 14 |
| Chân 27 | DB15 — Data bit 15 |
| Chân 28 | DB16 — Data bit 16 |
| Chân 29 | DB17 — Data bit 17 (MSB) |
| Chân 30 | DVDD — Digital supply voltage |
| Chân 31 | DGND — Digital ground |
| Chân 32 | BYTE — Byte/word select |
| Chân 33 | RESET — Reset input |
| Chân 34 | RANGE — Input range select |
| Chân 35 | NC — Not connected |
| Chân 36 | NC — Not connected |
| Chân 37 | AGND — Analog ground |
| Chân 38 | REFGND — Reference ground |
| Chân 39 | REF — Reference decoupling |
| Chân 40 | AVDD — Analog supply voltage |
| Chân 41 | AGND — Analog ground |
| Chân 42 | AVDD — Analog supply voltage |
| Chân 43 | IN+ — Positive differential analog input |
| Chân 44 | IN- — Negative differential analog input |
| Chân 45 | AVDD — Analog supply voltage |
| Chân 46 | AGND — Analog ground |
| Chân 47 | REF — Reference decoupling |
| Chân 48 | PowerPAD — Thermal pad (connect to AGND) |
Ứng dụng tiêu biểu
ADS8482IRGZR phù hợp cho 7 Áp dụngs: Industrial Process Control Data Acquisition, Medical Imaging Front End, Precision Weigh Scale and Load Cell Digitization, Optical Sensor and Photodiode Array Digitization, Vibration Analysis and Condition Monitoring, Automated Test Equipment (ATE) and Instrumentation, Power Quality and Energy Metering.
Industrial Process Control Data Acquisition
The ADS8482IRGZR's 18-bit resolution at 1 MSPS makes it a strong fit for multiplexed industrial process-control DAQ cards where one ADC serves multiple slow sensors. The 1 MSPS throughput supports 10 kHz per channel across 100+ channels with software sequencing, and the internal 4.096 V reference eliminates an external reference IC on the bill of materials. The pseudo-bipolar differential input directly digitizes ±10 V industrial signals after resistor-divider scaling, with common-mode noise rejection superior to single-ended ADCs in noisy factory environments. Unlike delta-sigma ADCs that introduce latency unsuitable for closed-loop control, the SAR architecture delivers single-cycle conversions enabling real-time PID feedback.
Được đề xuất
Medical Imaging Front End
The ADS8482IRGZR is suitable for medical imaging analog front ends such as ultrasound receive channels, CT detector preamps, and patient-monitoring signal chains. Its 18-bit resolution supports the wide dynamic range required to resolve small physiological signals in the presence of large DC offsets, and the 1 MSPS throughput accommodates multiplexed multi-channel probe assemblies. The internal low-drift 4.096 V reference simplifies BOM qualification under medical-device regulatory frameworks (IEC 60601 family) by reducing component count. The pseudo-bipolar differential input accommodates the bipolar outputs of ultrasound TGC amplifiers directly without additional level-shifting circuitry.
Được đề xuất
Precision Weigh Scale and Load Cell Digitization
The ADS8482IRGZR's 18-bit no-missing-codes performance and internal low-noise reference support direct digitization of bridge-type load cells in precision weigh scales. The differential input accepts the ratiometric output of a strain-gauge bridge tied to the 4.096 V reference, achieving effective system resolution beyond 16 bits after digital filtering. The 1 MSPS sample rate allows oversampling and averaging to push noise-free resolution into the 19-20 bit range for legal-for-trade and laboratory balance applications. Unlike a sigma-delta ADC, the SAR core delivers a fresh conversion every 1 us, supporting dynamic weighing scenarios such as checkweighers and in-motion scales.
Được đề xuất
Optical Sensor and Photodiode Array Digitization
The ADS8482IRGZR suits high-speed optical sensor readout such as CCD line arrays, photodiode arrays, and spectrometer detector boards. The 1 MSPS throughput supports kilohertz-line-rate line-scan cameras used in industrial inspection and spectroscopy, while the 18-bit dynamic range resolves both bright peaks and weak tails in a single scan. The pseudo-bipolar differential input accepts transimpedance-amplifier outputs biased to mid-scale, accommodating photodiode signals spanning both polarities of the reference. The internal 4.096 V reference provides a stable calibration point for photometric linearity, important in scientific and colorimetric instruments.
Được đề xuất
Vibration Analysis and Condition Monitoring
The ADS8482IRGZR delivers the dynamic range and bandwidth required for vibration analysis in condition-monitoring systems for motors, bearings, and rotating machinery. With 18-bit resolution sampled at 1 MSPS, the ADC captures spectral content well above the audio band necessary to detect bearing-fault signatures in the 10-50 kHz range. The SAR architecture provides deterministic per-sample timing, which simplifies synchronous sampling across multiple accelerometers. Unlike a delta-sigma ADC, the SAR latency is a single conversion cycle, enabling real-time envelope and RMS computations for predictive-maintenance algorithms running on the host processor.
Được đề xuất
Automated Test Equipment (ATE) and Instrumentation
The ADS8482IRGZR suits automated test equipment and bench instrumentation where 18-bit absolute accuracy at 1 MSPS is needed to characterize DUTs such as power supplies, DACs, and reference voltages. The internal 4.096 V reference provides a known calibration point, while the flexible 18/16/8-bit parallel interface simplifies connection to legacy 8-bit microcontrollers, modern 32-bit MCUs, or 18-bit ASIC testers. The pseudo-bipolar differential input allows direct measurement of bipolar signals without an input-conditioning amplifier, reducing measurement-path error. The 48-pin VQFN PowerPAD keeps the thermal rise low enough for high-accuracy measurements in densely populated ATE cards.
Được đề xuất
Power Quality and Energy Metering
The ADS8482IRGZR supports class-0.2 and class-0.5 energy-metering applications where simultaneous sampling of voltage and current channels with high dynamic range is required. The 1 MSPS sample rate easily covers harmonics up to the 40th harmonic of 50/60 Hz mains, while 18-bit resolution captures low-amplitude harmonic content critical for IEC 61000-4-7 compliance. The internal reference and differential inputs simplify the analog front end needed for Rogowski-coil and shunt-based current sensors. Using two ADS8482s in parallel allows simultaneous V/I sampling for three-phase meters without phase-delay distortion.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho ADS8482IRGZR — 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 | ADS8482IBRGZR | ADS8481IRGZR | ADS8472IRGZR | ADS8472IBRGZR |
|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 48-VQFN (RGZ) 7x7 mm | 48-VQFN (RGZ) - same | 48-VQFN (RGZ) - same | 48-VQFN (RGZ) - same | 48-VQFN (RGZ) - same |
| Resolution | 18 bit | 18 bit | 16 bit | 16 bit | 16 bit |
| Sample Rate | 1 MSPS | 1 MSPS | 1 MSPS | 1 MSPS | 1 MSPS |
| Internal Reference | 4.096 V | 4.096 V | 4.096 V | 4.096 V | 4.096 V |
| Input Topology | Pseudo-bipolar differential | Pseudo-bipolar differential | Pseudo-bipolar differential | True bipolar | True bipolar |
| Interface | Parallel 18/16/8-bit | Parallel 18/16/8-bit | Parallel 18/16/8-bit | Parallel 16/8-bit | Parallel 16/8-bit |
| Operating Temperature | -40C to +85C | -40C to +85C (industrial) | -40C to +85C | -40C to +85C | -40C to +85C (industrial) |
| Approx. Unit Price (qty 100) | $15.60 | ~$15.60 (similar die) | ~$12-13 (16-bit) | ~$13-14 (16-bit) | ~$13-14 (16-bit industrial) |
Bảo phân biệt quan trọng
- 18-bit resolution with internal 4.096 V reference in a single IC (vsADS8481IRGZR)
- Pseudo-bipolar differential input accepts bipolar signals directly (vsADS8472IRGZR)
- Selectable 18/16/8-bit parallel interface (vsADS8484 (external reference variant))
Ghi chú thiết kế
Decouple AVDD, DVDD and REF pins with low-ESR ceramic capacitors (typically 10 uF bulk + 0.1 uF HF) placed within 5 mm of the package. The internal 4.096 V reference requires a 10 uF X7R bypass on the REF pin to achieve datasheet SNR. Separate analog and digital ground planes tied at a single point near the IC minimize switching noise coupling into the SAR comparator.
Route the differential analog input traces (IN+, IN-) as a matched-length differential pair on the top layer over a continuous ground pour. Keep digital bus lines (DB0-DB17, CONVST, RD, CS, BUSY) routed away from the analog input traces and the REF pin. The 48-VQFN PowerPAD must be soldered to a flooded thermal pad with multiple thermal vias to the inner ground plane for rated theta_JA.
Pseudo-bipolar inputs require DC bias to mid-scale (2.048 V) via high-impedance resistor networks to handle negative input excursions without clipping. Forgetting the mid-scale bias causes the ADC to clip half the input range. Also note that choosing the 8-bit bus mode requires three read cycles to fetch a full 18-bit conversion result - software must issue all three RD strobes before the next CONVST pulse or data will be lost.
The BUSY signal falling edge marks the end of conversion and should be used to trigger the read cycle. Avoid driving CONVST and RD simultaneously; honor the datasheet timing parameters t_WH (CONVST pulse width) and t_RDL (RD low width) to avoid spurious conversions. For multi-MHz bus operation, source-terminate the parallel digital outputs near the IC to prevent ringing on the DB lines.
Thông tin tuân thủ
RoHS and lead-free compliance per TI product page. AEC-Q100 not applicable - the ADS8482 family targets industrial/medical, not automotive. Halogen-free status not explicitly stated in verified data.
