ADS7861IBRHBRG4 - Dual 12-Bit 500kSPS Simultaneous-Sampling ADC | TI
MPN: ADS7861IBRHBRG4 ✓ Hoạt độngADS7861IBRHBRG4 Tóm tắt
An analog-to-digital converter is a mixed-signal integrated circuit that quantizes a continuous analog waveform into discrete digital codes; simultaneous-sampling ADCs add per-channel track-and-hold amplifiers so all channels capture the input at one common edge, critical for phase-sensitive measurements. Within the broader taxonomy, the ADS7861 sits in the ADC/DAC family, precision-converter sub-class, successive-approximation register (SAR) sub-category, and is qualified for industrial (-40°C to +125°C) ambient operation including automotive temperature grades.
Key features of the ADS7861IBRHBRG4 include 12-bit no-missing-codes resolution, ±2 LSB INL (max), dual 2 µs throughput, and four fully-differential inputs arranged as two converter pairs. The serial interface operates in either 2-wire or 3-wire mode, supports daisy-chaining of multiple devices, and is compatible with standard SPI, QSPI, and MICROWIRE framers. A hardware RESET pin and a programmable CONVST trigger simplify timing in deterministic multi-ADC systems.
Architecturally, the device uses a charge-redistribution SAR core with input bandwidth exceeding the Nyquist limit, allowing accurate sampling of high-edge transient currents. Low aperture delay and matched internal S/H timing across the two ADCs guarantee channel-to-channel phase alignment within a few nanoseconds, even at full 500 kSPS throughput.
Typical applications include three-phase motor-control current and voltage sensing, multi-axis vibration and inertial measurement, simultaneous power-line voltage and current acquisition for power-quality and protective relays, and data-acquisition front-ends requiring per-channel timestamp integrity. Industrial process control loops and digital oscilloscope input stages benefit from the same-skew dual conversion.
When designing with the ADS7861, route the analog and digital grounds as a star at the exposed pad, place the 10 µF + 0.1 µF decoupling pair within 3 mm of AVDD, and keep the 50 MHz serial clock traces short and impedance-matched to avoid coupling into the analog front-end.
This page aggregates distributor pricing, drop-in package-compatible alternatives, and engineering notes beyond what the manufacturer datasheet alone provides, helping procurement and design engineers evaluate the ADS7861 in context.
Bộ thay thế dễ dàng lắp đặt cho ADS7861IBRHBRG4 — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
ADS7861IRHBR
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
ADS7861IBRHBT
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
ADS8361IRHBR
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
ADS7861IRHBT
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
ADS8361IRHBT
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
ADS7861IBRHBRG4 Tỷ lệ tối đa & tính chất điện
| Number of Bits | 12 |
| Sampling Rate (Per Second) | 500 kSPS |
| Number of Inputs | 4 (2 pairs, fully differential, simultaneous sampling) |
| Input Configuration | Fully differential, 2 + 2 channels |
| Data Interface | Serial (SPI/QSPI/MICROWIRE compatible) |
| Throughput per Channel | 2 µs |
| Number of ADC Channels | 2 (simultaneous sampling) |
| Architecture | SAR (Successive Approximation Register) |
| Reference Type | Internal |
| Hộp / Vỏ | 32-VFQFN Exposed Pad (RHB, 5x5 mm) |
| Nhiệt độ hoạt động | -40°C to +125°C |
| Temperature Grade | Automotive |
| INL (Max) | ±2 LSB |
| No Missing Codes | 12-bit (guaranteed) |
| Kiểu lắp đặt | Surface Mount |
| Packaging | Tape & Reel (TR) |
| Terminal Form | No Lead (HVQCCN) |
| Trạng thái RoHS | Compliant |
Cấu hình chân ADS7861IBRHBRG4
| Chân 1 | REFP — Reference capacitor positive terminal |
| Chân 2 | REFN — Reference capacitor negative terminal |
| Chân 3 | REFIN — External reference input / internal reference output |
| Chân 4 | RESET — Hardware reset input (active low) |
| Chân 5 | CS — Chip select (active low) |
| Chân 6 | CONVST_A — Conversion start, channel pair A |
| Chân 7 | CONVST_B — Conversion start, channel pair B |
| Chân 8 | SCLK — Serial clock input |
| Chân 9 | DOUT_A — Serial data output, channel pair A |
| Chân 10 | DOUT_B — Serial data output, channel pair B |
| Chân 11 | DVDD — Digital supply voltage |
| Chân 12 | DGND — Digital ground |
| Chân 13 | CHB0+ — Channel B positive differential input 0 |
| Chân 14 | CHB0- — Channel B negative differential input 0 |
| Chân 15 | CHB1+ — Channel B positive differential input 1 |
| Chân 16 | CHB1- — Channel B negative differential input 1 |
| Chân 17 | AGND — Analog ground |
| Chân 18 | AVDD — Analog supply voltage |
| Chân 19 | CHB1+ — Channel B positive differential input 1 (second instance per datasheet numbering) |
| Chân 20 | CHB1- — Channel B negative differential input 1 (second instance per datasheet numbering) |
| Chân 21 | CHB0+ — Channel B positive differential input 0 (second instance per datasheet numbering) |
| Chân 22 | CHB0- — Channel B negative differential input 0 (second instance per datasheet numbering) |
| Chân 23 | AGND — Analog ground |
| Chân 24 | AVDD — Analog supply voltage |
| Chân 25 | CHA0- — Channel A negative differential input 0 |
| Chân 26 | CHA0+ — Channel A positive differential input 0 |
| Chân 27 | CHA1- — Channel A negative differential input 1 |
| Chân 28 | CHA1+ — Channel A positive differential input 1 |
| Chân 29 | AGND — Analog ground |
| Chân 30 | AVDD — Analog supply voltage |
| Chân 31 | TAG — Tag pin for daisy-chain identification |
| Chân 32 | EP — Exposed thermal pad, must be soldered to analog ground |
Ứng dụng tiêu biểu
ADS7861IBRHBRG4 phù hợp cho 6 Áp dụngs: Three-Phase Motor Control Current Sensing, Multi-Axis Vibration and IMU Front-End, Three-Phase Power Quality and Protective Relay, Industrial Process Control Loop Input Module, Digital Oscilloscope and Data Acquisition Front-End, Automotive Sensor Interface Module.
Three-Phase Motor Control Current Sensing
Why the ADS7861IBRHBRG4 fits motor control: the device's simultaneous-sampling 2+2 channel architecture captures all three phase currents plus the DC-bus voltage at the exact same instant, eliminating the inter-channel skew that multiplexed ADCs introduce. With 500 kSPS per channel and 12-bit resolution, the converter supports field-oriented control (FOC) loop rates of 20-50 kHz while keeping current ripple quantization below 10 mA at a 50 A full-scale. How it is used: each phase current is conditioned through a shunt plus differential amplifier, fed into one of the four fully-differential inputs, with the FPGA/MCU issuing CONVST pulses synchronized to the PWM carrier. Performance trade-off: at 500 kSPS the ADC adds 2 µs conversion latency, well below the 10-20 µs PWM period, leaving headroom for control math.
Được đề xuất
Multi-Axis Vibration and IMU Front-End
Why this ADC fits vibration: simultaneous sampling of X/Y/Z accelerometer outputs on a single clock edge preserves phase relationships critical for modal analysis and modal-impact testing, while 500 kSPS per channel comfortably digitizes vibration signatures up to 200 kHz. The fully-differential inputs reject common-mode noise injected by long cable runs from MEMS sensors to the data-acquisition PCB. How it is used: each axis drives a dedicated AIN pair through an instrumentation front-end, with the SPI port streaming 12-bit codes to the host DSP at full throughput. Trade-off: the 12-bit envelope suits condition-monitoring accelerometers (typically 8-12 bits effective); step up to ADS8361IRHBR for 16-bit seismic applications.
Được đề xuất
Three-Phase Power Quality and Protective Relay
Why this part fits power-quality metering: the matched sample-and-hold of the two ADCs guarantees synchronous Va/Vb/Vc and Ia/Ib/Ic capture, the foundation for accurate true-RMS, harmonics (THD), and phase-angle calculations per IEC 61000-4-30. 12-bit resolution at full 500 kSPS provides 0.024% amplitude quantization at nominal 230 V line-to-neutral, adequate for class-A meters when paired with calibration. How it is used: instrument transformers step down line voltage and current, anti-alias filters precede the inputs, and a single CONVST trigger aligns all six measurements. Trade-off: for revenue-grade accuracy (0.2 class) the 16-bit ADS8361IRHBR remains the preferred drop-in.
Được đề xuất
Industrial Process Control Loop Input Module
Why the ADC fits process control: 4 fully-differential channels in a single 5x5 mm VQFN save board area versus four discrete single-channel ADCs, and the -40 to +125°C industrial temperature grade tolerates the cabinet thermal environment. Internal reference eliminates external REF components, simplifying IEC 61508 SIL-rated designs. How it is used: each input accepts a 4-20 mA current loop via a 250 Ω shunt or a thermocouple via a low-noise front-end, with the host PLC reading conversion results over SPI every 1-2 ms. Trade-off: galvanic isolation requires an external digital isolator on the SPI lines because the ADC does not integrate one.
Được đề xuất
Digital Oscilloscope and Data Acquisition Front-End
Why this ADC fits scopes: simultaneous sampling of two channels at 500 kSPS per channel is well-suited to low-frequency, multi-channel waveform capture in industrial scopes and bench DAQ cards. The 12-bit vertical resolution combined with matched aperture delay yields accurate differential measurements between channels. How it is used: dual-channel signal conditioning routes the inputs through programmable gain amplifiers, then into the ADS7861's differential inputs; results stream over SPI to an FPGA for triggering and timebase management. Trade-off: 12-bit resolution limits dynamic range to ~72 dB, so 14- or 16-bit upgrade parts (ADS8361IRHBR) are preferred for high-fidelity scopes.
Được đề xuất
Automotive Sensor Interface Module
Why this ADC fits automotive sensor modules: the -40 to +125°C industrial/automotive temperature grade plus the small 5x5 mm VQFN package allow deployment in tight engine-bay and chassis environments. Simultaneous sampling captures wheel-speed, steering-angle, and suspension-position sensors on the same edge for advanced driver-assistance systems (ADAS) that rely on phase-aligned inputs. How it is used: each sensor's conditioned analog output feeds one of the four differential inputs, with the host MCU reading conversion data over SPI at full throughput. Trade-off: AEC-Q100 Q1-qualified variants are not always in stock, so designers should validate availability when targeting automotive production programs.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho ADS7861IBRHBRG4 — 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 | ADS7861IRHBR | ADS7861IBRHBT | ADS8361IRHBR | ADS7861IRHBT | ADS8361IRHBT |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 32-VFQFN Exposed Pad (RHB, 5x5 mm) | 32-VFQFN Exposed Pad (RHB, 5x5 mm) - same | 32-VFQFN Exposed Pad (RHB, 5x5 mm) - same | 32-VFQFN Exposed Pad (RHB, 5x5 mm) - same | 32-VFQFN Exposed Pad (RHB, 5x5 mm) - same | 32-VFQFN Exposed Pad (RHB, 5x5 mm) - same |
| Resolution (Bits) | 12 | 12 | 12 | 16 (+33%) | 12 | 16 (+33%) |
| Sampling Rate (per channel) | 500 kSPS | 500 kSPS | 500 kSPS | 500 kSPS | 500 kSPS | 500 kSPS |
| Input Channels | 4 (2+2 simultaneous) | 4 (2+2 simultaneous) | 4 (2+2 simultaneous) | 4 (simultaneous) | 4 (2+2 simultaneous) | 4 (simultaneous) |
| Operating Temperature | -40°C to +125°C (Industrial/Automotive) | 0°C to +70°C (Commercial) | -40°C to +125°C (Industrial) | -40°C to +125°C | 0°C to +70°C (Commercial) | -40°C to +125°C |
| Interface | Serial (SPI/QSPI/MICROWIRE) | Serial (SPI/QSPI/MICROWIRE) | Serial (SPI/QSPI/MICROWIRE) | Serial (SPI/QSPI/MICROWIRE) | Serial (SPI/QSPI/MICROWIRE) | Serial (SPI/QSPI/MICROWIRE) |
| Architecture | SAR, simultaneous sampling | SAR, simultaneous sampling | SAR, simultaneous sampling | SAR, simultaneous sampling | SAR, simultaneous sampling | SAR, simultaneous sampling |
Bảo phân biệt quan trọng
- Industrial/automotive -40 to +125°C temperature grade in the same RHB footprint (vsADS7861IRHBR)
- Drop-in 16-bit resolution upgrade path (vsADS8361IRHBR)
- Matched internal sample-and-hold eliminates channel-to-channel skew (vsGeneric multiplexed 4-channel ADC architectures)
Ghi chú thiết kế
Use a star-ground topology tying AGND, DGND, and the exposed pad (pin 32) together at a single point under the IC. Place a 10 µF X7R ceramic plus a 0.1 µF X7R decoupling pair within 3 mm of each AVDD pin (18, 24, 30) and one similar pair on DVDD (pin 11). Keep the analog input traces matched-length within 0.5 mm so that differential pair skew does not degrade CMRR at the 500 kSPS edge rate.
Route the serial interface (SCLK, DOUT_A, DOUT_B, CS) over a continuous ground reference and keep digital traces away from the analog input pairs. The exposed pad must be soldered to a continuous copper pour with at least 8 thermal vias (0.3 mm drill, 1 mm pitch) to keep junction temperature within the 150°C limit when sampling multiple simultaneously-driven channels. Place a 10 µF + 0.1 µF capacitor at REFP/REFN (pins 1 and 2) to stabilize the internal reference.
Do not drive any analog input above AVDD + 0.3 V or below AGND - 0.3 V; the SAR front-end has no internal clamps and a momentary over-voltage can latch up the converter. Drive CONVST_A and CONVST_B with a clean low-jitter signal; any aperture jitter on these pins translates directly into sampled-data timing error in three-phase current loops. When using daisy-chain mode (TAG pin), assert CS only after the final device in the chain to avoid spurious conversions.
Thông tin tuân thủ
RoHS-compliant per Texas Instruments product page (G4 lead-free finish). Industrial/automotive temperature grade -40 to +125°C indicated by 'I' ordering code suffix; AEC-Q100 Q1-qualified variant not catalogued under this exact MPN suffix.
