AD7862ARS-3REEL - Dual 12-Bit 250kSPS ADC, ±2.5V | Analog Devices
MPN: AD7862ARS-3REEL ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $22.5 | $22.50 |
| 10 | $20.25 | $202.50 |
| 100 | $17.8 | $1,780.00 |
| 500 | $15.95 | $7,975.00 |
| 1,000 | $14.2 | $14,200.00 |
AD7862ARS-3REEL Overview
A successive-approximation ADC (SAR ADC) is a type of data converter that performs a binary search across an internal DAC to resolve an input voltage to N bits within a fixed number of conversion cycles. Dual-SAR ADCs place two complete SAR cores on one die, enabling truly simultaneous sampling of two signals - critical for power-converter control, motor drives, and multi-phase measurement where phase skew between channels would corrupt the result.
Key features of the AD7862ARS-3REEL include 250 kSPS per-channel throughput, simultaneous sampling across two channels (four inputs total), ±2.5 V bipolar input range (variant -3), 4 µs conversion time per channel, on-chip 2.5 V reference, overvoltage protection on analog inputs, low 60 mW typical power dissipation, and a 50 µW power-saving mode. The high-speed parallel interface simplifies connection to microcontrollers, DSPs, and FPGAs without external glue logic.
Typical applications include motor-control current sensing, three-phase power-line monitoring, multi-axis inertial measurement, data-acquisition front ends, and instrumentation. The simultaneous-sampling dual-core topology removes inter-channel skew, while the ±2.5 V range handles industrial signal levels without external attenuators.
When designing with this part, place 0.1 µF decoupling capacitors close to each supply pin and keep analog/digital grounds separated until they join at the ADC GND pin. The internal 2.5 V reference can be bypassed with a 10 µF tantalum capacitor for low-noise operation; an external reference may be used for higher accuracy.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not typically aggregated on the Analog Devices product page.
Drop-in alternatives for AD7862ARS-3REEL — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with AD7862ARS-3REEL (same form factor and footprint) — differing in Architecture, Number of Inputs, Package / Case, Packaging, Power Dissipation (typical).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
AD7862ARSZ-3REEL
✅ Drop-In📋 Reference alternative (not in catalog)
AD7862ARS-3
✅ Drop-In📋 Reference alternative (not in catalog)
AD7862ARSZ-3
✅ Drop-In📋 Reference alternative (not in catalog)
AD7862AR-3REEL
✅ Drop-In📋 Reference alternative (not in catalog)
AD7862ARS-2REEL
✅ Drop-In✓ In Stock
$14.85 / Unit
View Datasheet →AD7862ARS-3REEL Maximum Ratings & Electrical Characteristics
| Manufacturer | Analog Devices |
| Part Number | AD7862ARS-3REEL |
| Number of Bits | 12 |
| Number of Inputs | 4 (2 channels, simultaneous sampling) |
| Sampling Rate (Per Second) | 250 kSPS per channel |
| Conversion Time | 4 µs |
| Data Interface | Parallel |
| Input Range (variant -3) | ±2.5 V |
| Supply Voltage | +5 V single supply |
| Power Dissipation (typical) | 60 mW |
| Power-Saving Mode | 50 µW typical |
| Internal Reference | +2.5 V |
| Track-and-Hold Amplifiers | 2 (one per channel) |
| Architecture | Dual SAR |
| Analog Input Protection | Overvoltage protected |
| Package / Case | 28-SSOP (0.209", 5.30 mm width) |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel (TR) |
AD7862ARS-3REEL Pin Configuration
| Pin 1 | VA1+ — Analog input channel A1 positive (variant -3: ±2.5 V range) |
| Pin 2 | VA1- — Analog input channel A1 negative |
| Pin 3 | VA2+ — Analog input channel A2 positive |
| Pin 4 | VA2- — Analog input channel A2 negative |
| Pin 5 | AGND — Analog ground |
| Pin 6 | VREF — Reference voltage output / input (2.5 V nominal) |
| Pin 7 | VDD — +5 V analog supply |
| Pin 8 | REFSENSE — Reference sense input |
| Pin 9 | DGND — Digital ground |
| Pin 10 | CONVST — Conversion start input |
| Pin 11 | BUSY — Busy output (active during conversion) |
| Pin 12 | RD — Read input (active low) |
| Pin 13 | CS — Chip select (active low) |
| Pin 14 | A0 — Channel select input (0 = channel A, 1 = channel B) |
| Pin 15 | HBEN — High byte enable (DB8-DB11 vs DB0-DB11) |
| Pin 16 | DB11/MSB — Data bit 11 (MSB) / parallel output |
| Pin 17 | DB10 — Data bit 10 |
| Pin 18 | DB9 — Data bit 9 |
| Pin 19 | DB8 — Data bit 8 |
| Pin 20 | DB7 — Data bit 7 |
| Pin 21 | DB6 — Data bit 6 |
| Pin 22 | DB5 — Data bit 5 |
| Pin 23 | DB4 — Data bit 4 |
| Pin 24 | DB3 — Data bit 3 |
| Pin 25 | DB2 — Data bit 2 |
| Pin 26 | DB1 — Data bit 1 |
| Pin 27 | DB0/LSB — Data bit 0 (LSB) |
| Pin 28 | NC — Not connected (per datasheet) |
Typical Applications
AD7862ARS-3REEL is suitable for 7 applications: Motor Control Current Sensing, Three-Phase Power-Line Monitoring, Multi-Axis Inertial Measurement, Industrial Data Acquisition Front Ends, Servo-Drive Position Feedback, Audio Spectrum Analyzer Front End, Medical Patient Monitoring Equipment.
Motor Control Current Sensing
The AD7862ARS-3REEL's dual simultaneous-sampling SAR architecture fits three-phase motor-control current sensing where phase-to-phase skew corrupts field-oriented control (FOC) loops. With ±2.5 V input range and 250 kSPS per channel, two current transformers or shunt-amplifier outputs can be digitized at full rate through one IC, removing the need for two synchronized ADCs. The 4 µs conversion time keeps control-loop latency under 1 PWM cycle at typical 20 kHz switching frequencies. Compared to a multiplexer + single-ADC architecture, simultaneous sampling removes inter-channel sample-skew errors that manifest as torque ripple in FOC drives. Recommend pairing with ADuM3151 isolators and AMC1301 reinforced-isolated shunt amplifiers for high-voltage IGBT/SiC inverter platforms.
Recommended
Three-Phase Power-Line Monitoring
The AD7862ARS-3REEL suits three-phase power-quality and revenue-metering front ends where four channels need simultaneous sampling at modest rates. The ±2.5 V range matches CT/PT-derived signals after scaling resistors; the 250 kSPS per-channel rate captures up to the 50th harmonic on 50/60 Hz mains. Two ADC cores mean phases A and B (and optionally C) can be captured on one device, reducing board area and BOM cost versus two cascaded converter stages. The parallel interface streams 12-bit samples directly into an FPGA or DSP for FFT-based harmonic analysis. The 60 mW typical dissipation and 50 µW power-down mode help meet IEC 62053-22 idle-power budgets.
Recommended
Multi-Axis Inertial Measurement
The AD7862ARS-3REEL is used in inertial measurement units (IMUs) where 3-axis gyroscope and accelerometer outputs must be sampled simultaneously. Simultaneous acquisition removes the 1 µs+ skew that single-ADC + mux designs introduce at 250 kSPS, which corrupts attitude estimates during high angular-rate maneuvers. The four input channels support XYZ gyro plus one spare reference channel. The internal 2.5 V reference simplifies the analog supply chain, and the small 28-SSOP footprint fits space-constrained flight-controller PCBs. For higher-precision IMU designs, the AD7693 16-bit pin-compatible upgrade offers 4× resolution at lower speed; for higher shock survivability, pair the analog front end with ADXRS645 gyros.
Recommended
Industrial Data Acquisition Front Ends
General-purpose industrial DAQ systems use the AD7862ARS-3REEL to digitize up to four ±2.5 V signals per device with simultaneous sampling. The 250 kSPS rate supports vibration, strain-gauge bridge, and process-control transducer inputs. The 28-SSOP package supports hand-prototyping on through-hole-to-SSOP adapter boards as well as high-density SMT assembly. The parallel interface glues directly to 8/16-bit microcontrollers and 32-bit FPGAs without glue logic. Engineers typically pair this part with the AD8221 instrumentation amplifier for low-level sensor signals and the AD780 precision reference for enhanced accuracy when the internal 2.5 V reference is bypassed.
Recommended
Servo-Drive Position Feedback
The AD7862ARS-3REEL is well-suited to digitizing resolver/encoder-derived analog position signals in high-bandwidth servo drives. The dual simultaneous-sampling inputs can capture sine and cosine windings of a resolver synchronously, after r/d conversion. The 12-bit resolution gives 0.088° position resolution - sufficient for mid-range servo loops; the ±2.5 V input range matches resolver excitation-derived signals. The 250 kSPS per-channel rate easily handles 20 kHz current-loop update rates with margin. For 16-bit precision servo designs, the AD7690 pin-compatible upgrade is available.
Recommended
Audio Spectrum Analyzer Front End
The AD7862ARS-3REEL can serve as the front-end ADC of an audio spectrum analyzer operating from a few hundred Hz to ~100 kHz. The 250 kSPS per-channel rate and 12-bit resolution capture the audio band without aliasing, while dual-channel sampling supports stereo input or single-ended/differential comparison. The ±2.5 V input range is ideal for line-level audio after DC blocking. The parallel interface pushes samples directly into an FPGA for FFT processing. For higher-fidelity 24-bit designs, the AD7768 series is the natural upgrade path; for portable audio analyzers, the AD1974 4-channel ADC provides higher channel density.
Recommended
Medical Patient Monitoring Equipment
The AD7862ARS-3REEL fits medical patient-monitoring equipment such as multi-channel ECG, EEG, or pulse-oximetry front ends where two simultaneous waveforms need synchronous acquisition. The 250 kSPS per-channel rate handles high-resolution ECG (typically 1-10 kHz sample rate), and the internal 2.5 V reference simplifies design for IEC 60601-1 isolated patient circuits. The 12-bit resolution is adequate for mid-tier monitoring; defibrillator-proof designs may use the ADAS1000 family which integrates respiration, impedance, and pace-detection. Always add appropriate isolation amplifiers (ADuM3151) and IEC 60601-1 compliant power for patient-contact designs.
Recommended
Recommended Products Summary
Engineering reference data for AD7862ARS-3REEL — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | AD7862ARSZ-3REEL | AD7862ARS-3 | AD7862ARSZ-3 | AD7862AR-3REEL | AD7862ARS-2REEL |
|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 28-SSOP | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same | 28-SSOP - same |
| Resolution | 12-bit | 12-bit | 12-bit | 12-bit | 12-bit | 12-bit |
| Input Range | ±2.5 V | ±2.5 V | ±2.5 V | ±2.5 V | ±2.5 V | 0 V to 2.5 V (unipolar) |
| Sampling Rate | 250 kSPS/channel | 250 kSPS/channel | 250 kSPS/channel | 250 kSPS/channel | 250 kSPS/channel | 250 kSPS/channel |
| Architecture | Dual simultaneous SAR | Dual simultaneous SAR | Dual simultaneous SAR | Dual simultaneous SAR | Dual simultaneous SAR | Dual simultaneous SAR |
| Supply Voltage | +5 V single | +5 V single | +5 V single | +5 V single | +5 V single | +5 V single |
| Packaging | Tape & Reel | Tape & Reel | Tube | Tube | Tape & Reel | Tape & Reel |
| RoHS Compliant | Unknown (no Z suffix) | Yes (Z suffix = Pb-free) | Unknown | Yes (Z suffix = Pb-free) | Unknown | Unknown |
Key Differentiators
- Dual simultaneous-sampling SAR architecture on a single 28-SSOP die (vs AD7862ARS-2REEL)
- RoHS variant available as drop-in replacement (vs AD7862ARSZ-3REEL)
- Pin-compatible 14-bit upgrade path (vs AD7863 family)
Design Notes
Decouple VDD with a 10 µF tantalum in parallel with a 0.1 µF ceramic placed as close as possible to the VDD pin; the AD7862 draws up to 12 mA from a +5 V supply. Add a separate digital supply pin decoupling (0.1 µF) if your layout exposes a distinct digital VDD node. Estimated: 60 mW typical dissipation implies ~12 mA average supply current at +5 V.
Use a star-ground topology with the AD7862 GND pin as the single point where AGND and DGND meet. Route analog input traces (VA1+, VA1-, VA2+, VA2-) symmetrically and keep them short; the ±2.5 V input range is moderately sensitive to ground-bounce-induced common-mode errors. Place the internal 2.5 V reference bypass capacitor (10 µF recommended by Analog Devices) adjacent to VREF with a minimal loop area to preserve noise performance.
Ensure the BUSY signal is correctly monitored - data is valid only after BUSY returns high. For simultaneous acquisition, drive CONVST once and read both channels after a single BUSY cycle. Do not exceed ±2.5 V on analog inputs; the on-chip overvoltage protection clamps at higher voltages but continuous overdrive degrades input-impedance matching. When migrating from the -3 (±2.5 V) to the -2 (0 V to 2.5 V) variant, recalibrate any bipolar-system scaling resistors as the input range changes substantially.
The parallel data bus (DB0-DB11) transitions on every conversion at 250 kSPS - route these traces over a continuous ground plane and add 33 Ω series termination if the bus length exceeds ~50 mm to dampen reflections. The BUSY and CONVST signals are timing-critical; keep them short and away from noisy digital lines. For EMC-sensitive designs, place a ferrite bead on the digital supply rail feeding the AD7862.
Compliance Information
RoHS status not stated in verified web data; the Z-suffix variant (AD7862ARSZ-3REEL) is Pb-free per Analog Devices part-numbering convention. AEC-Q100 not applicable as this part is intended for industrial/test/measurement applications, not automotive qualified.
