ADS8401IBPFBR - 16-Bit 1.25MSPS SAR ADC w/ Ref | Texas Instruments
MPN： ADS8401IBPFBR ✓ 啟用中ADS8401IBPFBR 概覽
A SAR ADC is a type of data converter that uses a binary-search algorithm against an internal capacitive DAC to digitize an analog input in a fixed number of clock cycles. SAR ADCs sit within the broader hierarchy of analog-to-digital converters, between flash converters (fastest, lowest resolution) and sigma-delta converters (highest resolution, lowest bandwidth). Because SAR ADCs offer deterministic latency, no pipeline delay, and excellent AC/DC accuracy at medium speeds, they are preferred for multiplexed multi-channel systems, motor control, and precision instrumentation where single-shot accuracy matters more than continuous streaming throughput.
Key features of the ADS8401 include 1.25 MSPS sampling rate, internal low-drift 4.096 V reference, 16-bit parallel (unipolar) interface, single 5 V analog supply, low power consumption (approximately 110 mW typical at 1.25 MSPS), and -40 C to +85 C industrial operating range. The internal reference eliminates the need for an external reference IC, reducing BOM count and PCB area. The PFB-48 package provides a 7x7 mm footprint with industry-standard 0.5 mm lead pitch for surface-mount assembly.
The architecture combines a high-bandwidth input sample-and-hold, a precision 16-bit charge-redistribution DAC, and a low-noise internal reference buffered for low-impedance drive. The internal reference achieves low drift, supporting 16-bit integral nonlinearity (INL) and differential nonlinearity (DNL) without external calibration. Conversion is initiated on the falling edge of CONVST, and data is latched into the output bus after a deterministic number of clock cycles, simplifying FPGA/CPLP interface timing.
Typical applications include industrial process control, multichannel data acquisition systems (DAQ), optical encoders and position feedback loops, medical instrumentation, vibration analysis, and power-line monitoring. The 1.25 MSPS throughput supports per-channel sampling in multiplexed 4- to 8-channel systems running at 100 kSPS to 300 kSPS per channel. The integrated reference is particularly attractive when board space and BOM simplicity are priorities.
When designing with the ADS8401, ensure the analog input signal is fully settled within the 320 ns acquisition window. Use a low-impedance input buffer (such as the OPA227 or THS4031) to drive the ADC input, and decouple the AVDD pin with a 10 uF tantalum and 0.1 uF ceramic capacitor combination placed as close to the pin as possible. Avoid routing digital output bus traces beneath the analog input pin to minimize digital-to-analog coupling.
This page synthesizes distributor inventory, drop-in alternative cross-references, and practical design notes not found in the manufacturer datasheet alone. Pin-compatible alternates are listed by same-brand first, then cross-brand, with parametric proximity scoring. All alternatives share the 48-TQFP (PFB) footprint.
直接替換替代品，適用於 ADS8401IBPFBR — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： ADS8401IBPFBR （相同外形與佔位） — 差異在於 Input Type, Package, Analog Supply Voltage, Operating Temperature, Sample Rate.
ADS8401IBPFBTG4
✅ 直接替換聯絡詢價
查看資料表 →ADS8405IPFBTG4
✅ 直接替換📋 參考替代品（不在目錄中）
ADS8411IBPFBT
✅ 直接替換📋 參考替代品（不在目錄中）
ADS8381IBPFBR
✅ 直接替換聯絡詢價
查看資料表 →ADS8422IBPFBR
✅ 直接替換📋 參考替代品（不在目錄中）
ADS8401IBPFBR 最大額定值與電氣特性
| 解析度 | 16 bit |
| Architecture | SAR (Successive Approximation Register) |
| Number of Input Channels | 1 |
| 取樣率 | 1.25 MSPS |
| Analog Input Type | Single-ended, unipolar |
| 輸入電壓範圍 | 0 V to VREF |
| Internal Reference Voltage | 4.096 V |
| Digital Interface | Parallel (16-bit, unipolar) |
| Analog Supply Voltage | 5 V (single supply) |
| Power Dissipation (typical) | 110 mW at 1.25 MSPS |
| 工作溫度範圍 | -40 C to +85 C (Industrial) |
| 封裝 | 48-pin TQFP (PFB) 7x7 mm |
| Lead Pitch | 0.5 mm |
| 安裝類型 | Surface Mount |
| MSL 等級 | 2 (1 year floor life) |
| RoHS 狀態 | Compliant |
| Lead-Free | Yes |
ADS8401IBPFBR 48-pin tqfp (pfb) 7x7 mm 腳位配置指南
ADS8401IBPFBR（48-pin tqfp (pfb) 7x7 mm 封裝）的腳位配置。 此類比元件具有輸入、輸出與電源腳位。偏移歸零、補償與致能腳位配置請參閱製造商資料表。適用於訊號調理與放大器電路。
無詳細腳位定義資料： ADS8401IBPFBR.
請參閱 資料表 以查看完整腳位配置。
典型應用
ADS8401IBPFBR 適用於 6 應用s: Industrial Process Control and Data Acquisition, Optical Encoder and Position Feedback, Medical Instrumentation and Patient Monitoring, Vibration Analysis and Condition Monitoring, Power-Line Monitoring and Energy Metering, Automated Test Equipment (ATE) and Bench Instruments.
Industrial Process Control and Data Acquisition
The ADS8401IBPFBR is well matched to industrial process-control DAQ systems requiring 16-bit precision at 1.25 MSPS throughput. The single-channel SAR architecture with deterministic latency fits multiplexed multi-channel signal chains running 100 to 300 kSPS per channel across 4 to 8 channels. The industrial -40 C to +85 C operating range and integrated 4.096 V reference reduce BOM complexity for cost-sensitive factory-floor deployments. Unlike sigma-delta converters, the SAR core provides single-cycle conversion without digital filtering latency, simplifying control-loop timing.
推薦
Optical Encoder and Position Feedback
The ADS8401IBPFBR suits optical-encoder readout and position-feedback loops in servo and motion-control systems. The 1.25 MSPS sampling rate supports high-bandwidth position tracking, while the 16-bit resolution delivers sub-arc-minute angular resolution when paired with a high-precision linear or rotary encoder. The deterministic SAR conversion latency simplifies control-loop compensation, and the parallel output interface allows direct connection to FPGAs implementing PID loops. The integrated 4.096 V reference eliminates the need for a separate precision reference on the encoder board.
推薦
Medical Instrumentation and Patient Monitoring
The ADS8401IBPFBR is used in medical instrumentation where 16-bit accuracy and deterministic sampling matter more than continuous-streaming throughput. Patient monitors, ECG front-end digitizers, and blood-pressure measurement modules benefit from the SAR core's single-cycle conversion with no pipeline delay. The 1.25 MSPS sampling rate supports high-bandwidth bioelectric signal capture, and the low 110 mW power dissipation simplifies thermal management in compact bedside devices. The integrated reference reduces calibration complexity, an important consideration for IEC 60601-compliant medical equipment.
推薦
Vibration Analysis and Condition Monitoring
The ADS8401IBPFBR supports vibration analysis in condition-monitoring systems for predictive maintenance on rotating machinery such as motors, pumps, and fans. The 1.25 MSPS rate captures vibration frequencies well above 50 kHz when preceded by appropriate anti-aliasing filters, allowing frequency-domain analysis of bearing faults and imbalance signatures. The 16-bit dynamic range (approximately 96 dB) suits envelope-analysis techniques for early fault detection. SAR conversion provides instantaneous amplitude snapshots without the group delay of sigma-delta modulators, preserving phase relationships across multiple measurement channels.
推薦
Power-Line Monitoring and Energy Metering
The ADS8401IBPFBR is a strong fit for power-line monitoring and energy-metering front-ends requiring 16-bit accuracy at multi-kHz sampling rates. The device captures instantaneous voltage and current waveforms at 1.25 MSPS, well above the Nyquist requirement for 50/60 Hz line-frequency analysis and harmonic content up to the 40th harmonic or beyond. The integrated reference reduces drift in computed RMS and active-power values, while the SAR latency is acceptable for non-real-time metering. Industrial temperature rating supports outdoor cabinet and substation deployments.
推薦
Automated Test Equipment (ATE) and Bench Instruments
The ADS8401IBPFBR delivers 16-bit precision in bench-top instruments and automated test equipment where multi-channel throughput and signal fidelity are critical. The 1.25 MSPS sampling rate supports waveform capture, digitizer modules, and characterization systems. The parallel interface eases integration with FPGAs implementing timing generators and trigger logic, while the integrated reference simplifies calibration routines. The industrial temperature range and proven SAR architecture make this part a long-term mainstay in measurement-grade instrumentation requiring years of production availability.
推薦
推薦產品摘要
工程參考資料，適用於 ADS8401IBPFBR — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | ADS8401IBPFBTG4 | ADS8405IPFBTG4 | ADS8411IBPFBT | ADS8381IBPFBR | ADS8422IBPFBR |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 48-TQFP (PFB) 7x7 mm | 48-TQFP (PFB) 7x7 mm - same | 48-TQFP (PFB) 7x7 mm - same | 48-TQFP (PFB) 7x7 mm - same | 48-TQFP (PFB) 7x7 mm - same | 48-TQFP (PFB) 7x7 mm - same |
| Resolution | 16 bit | 16 bit | 16 bit | 16 bit | 18 bit | 16 bit |
| Sampling Rate | 1.25 MSPS | 1.25 MSPS | 1.25 MSPS | 2 MSPS | 1 MSPS | 4 MSPS |
| Internal Reference | 4.096 V | 4.096 V | 2.5 V / 4.096 V (selectable) | 4.096 V | Internal ref | Internal ref |
| Interface | Parallel (16-bit) | Parallel (16-bit) | Parallel (16-bit) | Parallel (16-bit / 8-bit mode) | Parallel (18-bit) | Parallel (16-bit) |
| Supply Voltage | 5 V single | 5 V single | 5 V single | 5 V single | 5 V single | 5 V single |
| Operating Temperature | -40 C to +85 C (Industrial) | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
主要差異化特點
- Integrated 4.096 V reference eliminates external reference IC (對比ADS8411IBPFBT)
- Direct 5 V single-supply operation simplifies power design (對比ADS8422IBPFBR)
- Industrial temperature range as standard (對比ADS8381IBPFBR)
設計說明
Place the 10 uF tantalum and 0.1 uF ceramic decoupling capacitors on AVDD and DVDD as close to the device pins as possible. Use a separate analog ground plane tied to a single point to the digital ground at the ADC GND pin. Avoid routing the parallel digital output bus beneath the analog input trace on adjacent layers; keep digital signals at least 5 mm away from the analog input or use a guard ground trace. The exposed thermal pad of the TQFP package should be soldered to a copper pour for thermal relief, even though the part dissipates only 110 mW typical.
Do not drive the analog input directly from a high-impedance source; the sample-and-hold stage requires settling within 320 ns to achieve 1.25 MSPS at 16-bit accuracy. Always use a low-impedance, low-distortion buffer amplifier (such as OPA227 or THS4031) to drive the IN pin. The CONVST signal must be clean and monotonic; long CONVST traces or shared digital lines can introduce aperture jitter and degrade SNR. Confirm that the input signal range stays within 0 V to VREF - inputs above VREF can damage the device or cause erroneous code conversion.
The parallel 16-bit output bus can generate significant switching noise on the digital supply. Place 33 ohm series damping resistors at the ADC output pins if the bus length exceeds 50 mm, to slow edge rates and reduce SSO (simultaneous switching output) ground bounce. Maintain matched trace lengths on DB0 through DB15 to within 5 mm to preserve data valid window timing at the host FPGA or DSP. Add a buffer (such as 74LVC245) if more than one load drives the bus, but place the buffer within 25 mm of the ADC outputs.
合規資訊
RoHS compliant per TI product page. Industrial -40 C to +85 C temperature grade; not AEC-Q100 qualified for automotive applications.
