ADS1286UC/2K5 - 12-Bit 20kHz Micro-Power SAR ADC | Texas Instruments
MPN: ADS1286UC/2K5 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $14.17 | $14.17 |
| 10 | $12.74 | $127.40 |
| 100 | $11.31 | $1,131.00 |
| 500 | $9.89 | $4,945.00 |
| 1,000 | $8.46 | $8,460.00 |
ADS1286UC/2K5 Overview
An SAR ADC (Successive Approximation Register Analog-to-Digital Converter) is a type of data converter that uses a binary search algorithm and an internal DAC to resolve an analog input one bit per clock cycle. SAR ADCs sit within the broader hierarchy: ADC → data converter → mixed-signal IC → semiconductor. Compared to delta-sigma ADCs, SAR converters offer deterministic latency, no pipeline delay, and lower power consumption at sample rates up to a few MSPS, which is why they remain the workhorse for multiplexed data-acquisition systems and motor-control current sensing.
Key differentiating specifications include 12-bit resolution with no missing codes, 20 kHz maximum sample rate, 250 µA quiescent supply current, and a wide single-supply operating range (typically 4.5 V to 5.25 V). The integrated differential input eliminates the need for external instrumentation amplifiers in many sensor-conditioning paths, and the synchronous serial interface allows direct connection to microcontrollers and DSPs without glue logic.
Architecture-wise, the ADS1286 combines a capacitive-charge-distribution DAC, a high-gain comparator, and an SAR control logic block. A single conversion cycle takes 16 internal clock periods, with the sample-and-hold acquiring on the falling edge of CS and conversion starting on the rising edge. The device requires an external reference voltage and an external serial clock, keeping the analog front-end compact and predictable.
Typical applications include portable instrumentation, weigh scales, remote sensors, process-control loops, and battery-powered data loggers. Industrial-grade temperature range (-40 °C to +85 °C) and the small SOIC-8 footprint suit it to space-constrained embedded designs.
A primary design consideration is the input common-mode range, which must stay within the supply rails; for true bipolar signals, consider a true bipolar-input ADC such as the ADS1287 family. The /CS pin doubles as the conversion-start trigger, so firmware timing must respect the 16-clock conversion window to avoid corrupted results.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for ADS1286UC/2K5 — 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 ADS1286UC/2K5 (same form factor and footprint) — differing in Operating Temperature, Package, Input Type, Resolution, Sample Rate.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ADS1286UA/2K5G4
✅ Drop-In📋 Reference alternative (not in catalog)
ADS1286U/2K5
✅ Drop-In📋 Reference alternative (not in catalog)
ADS1286UL/2K5
✅ Drop-In📋 Reference alternative (not in catalog)
ADC121S101CIMFX
✅ Drop-In✓ In Stock
$1.85 / Unit
View Datasheet →ADC101S021CISDX
✅ Drop-In✓ In Stock
$1.32 / Unit
View Datasheet →ADC102S101CIMM
✅ Drop-In✓ In Stock
$1.55 / Unit
View Datasheet →ADS1286UC/2K5 Maximum Ratings & Electrical Characteristics
| Resolution | 12 bits |
| Sample Rate | 20 kHz maximum |
| Architecture | SAR (Successive Approximation Register) |
| Number of Channels | 1 |
| Input Type | Differential |
| Supply Current | 250 µA (typical) |
| Analog Supply Voltage | 5 V (single supply) |
| Digital Supply Voltage | 5 V (single supply) |
| Analog Input Range | 0 V to 5 V |
| Interface | SPI / SSI compatible, 2- or 3-wire serial |
| Missing Codes | Guaranteed none (12-bit, no missing codes) |
| Reference | External |
| Operating Temperature | -40 °C to +85 °C (industrial) |
| Package | SOIC-8 (D) 3.90 mm |
| Mounting Type | Surface Mount |
| MSL Level | 1 (unlimited) |
| RoHS Status | Compliant |
ADS1286UC/2K5 Pin Configuration
| Pin 1 | /CS — Chip Select, active low; falling edge triggers sample-and-hold |
| Pin 2 | SCLK — Serial Clock input |
| Pin 3 | DOUT — Serial Data Output |
| Pin 4 | GND — Ground |
| Pin 5 | REF+ — External Reference Voltage positive input |
| Pin 6 | IN- — Differential Analog Input negative |
| Pin 7 | IN+ — Differential Analog Input positive |
| Pin 8 | VDD — +5 V Analog and Digital Supply |
Typical Applications
ADS1286UC/2K5 is suitable for 6 applications: Weigh Scales and Load Cells, Portable Instrumentation and Data Loggers, Process Control and Industrial Sensors, Remote and Wireless Sensor Nodes, Battery Monitoring and Fuel Gauging, Motor Control Current Sensing.
Weigh Scales and Load Cells
The ADS1286UC/2K5's 12-bit no-missing-codes resolution and differential input pair directly with a Wheatstone bridge load cell, while the 250 µA supply current keeps battery-powered scales operational for months. The integrated sample-and-hold captures the bridge output in one cycle, eliminating external amplifier settling time and allowing 20 kHz throughput to track rapidly changing weight. The SOIC-8 footprint fits inside a sealed load-cell housing.
Recommended
Portable Instrumentation and Data Loggers
The 250 µA typical supply current and 5 V single-supply operation make the ADS1286UC/2K5 a natural fit for battery-powered data loggers measuring temperature, pressure, or voltage. The serial 2-wire or 3-wire interface minimizes microcontroller pin usage, leaving GPIOs available for sensors, displays, and SD-card storage. Industrial -40 °C to +85 °C operation supports outdoor and field-deployable instruments.
Recommended
Process Control and Industrial Sensors
The differential input rejects common-mode noise from 4-20 mA loops and 24 V industrial backplanes, and the 12-bit no-missing-codes performance delivers reliable readings of pressure, flow, and level transmitters. The ADS1286UC/2K5's deterministic 16-clock latency enables precise time-stamping of multiplexed channels in SCADA and PLC analog input modules. SOIC-8 industrial-grade construction survives factory-floor environments.
Recommended
Remote and Wireless Sensor Nodes
The ADS1286UC/2K5's 250 µA supply current draws negligible power from the host node's coin-cell or LiSOCl2 battery, and the 2-wire SSI interface connects directly to a sub-GHz radio SoC's SPI port. The differential input tolerates long twisted-pair cable runs from the sensor to the wireless node, rejecting ground-bounce noise that single-ended ADCs would convert into bit errors in RSSI calibration.
Recommended
Battery Monitoring and Fuel Gauging
The differential input of the ADS1286UC/2K5 measures across a current-sense shunt, while the 0-5 V input range covers stacked Li-ion cell voltages through a simple resistor divider. Micro-power consumption preserves battery capacity during standby, and the 20 kHz sample rate captures transient inrush current during system startup. SOIC-8 industrial-grade operation suits automotive and e-mobility battery packs.
Recommended
Motor Control Current Sensing
The deterministic SAR conversion completes in 16 SCLK cycles, enabling the ADS1286UC/2K5 to sample shunt-resistor current in perfect synchronization with the PWM cycle in FOC motor control loops. The 12-bit resolution is sufficient for torque estimation in small BLDC and stepper systems, and the 20 kHz rate matches typical PWM frequencies up to 10 kHz. The differential input rejects switching noise from the half-bridge.
Recommended
Recommended Products Summary
Engineering reference data for ADS1286UC/2K5 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADS1286UA/2K5G4 | ADS1286U/2K5 | ADS1286UL/2K5 | ADC121S101CIMFX | ADC101S021CISDX | ADC102S101CIMM |
|---|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | SOIC-8 (D) | SOIC-8 (D) - same | SOIC-8 (D) - same | SOIC-8 (D) - same | SOIC-8 (D) - same | SOIC-8 (D) - same | MSOP-8 / SOIC-8 - same |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits | 10 bits | 10 bits |
| Sample Rate | 20 kSPS | 20 kSPS | 20 kSPS | 20 kSPS | 1 MSPS | 200 kSPS | 1 MSPS |
| Input Type | Differential | Differential | Differential | Differential | Single-ended | Single-ended | Single-ended |
| Supply Voltage | 5 V (single) | 5 V (single) | 5 V (single) | 2.7 V to 5.25 V | 2.7 V to 5.25 V | 2.7 V to 5.25 V | 2.7 V to 5.25 V |
| Interface | SPI/SSI 2- or 3-wire | SPI/SSI 2- or 3-wire | SPI/SSI 2- or 3-wire | SPI/SSI 2- or 3-wire | SPI | SPI | SPI |
| Operating Temperature | -40 °C to +85 °C | -40 °C to +85 °C | 0 °C to +70 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C |
Key Differentiators
- Differential input in SOIC-8 at micro-power consumption (vs ADC101S021CISDX)
- Ultra-low 250 µA supply current (vs ADC121S101CIMFX)
- Industrial -40 °C to +85 °C temperature grade (vs ADS1286U/2K5)
Design Notes
The ADS1286UC/2K5 draws 250 µA typical from a single 5 V supply, but the supply pin should be decoupled with a 10 µF tantalum and a 100 nF ceramic capacitor placed within 5 mm of the VDD pin. Estimated: at 250 µA, average power dissipation is 1.25 mW, so no special thermal management is needed. For battery-powered applications, gate the VDD supply with a low-Iq LDO to extend shelf life when the ADC is not in use.
Keep the analog input traces (IN+, IN-) as short and symmetric as possible, and route them away from digital switching signals (SCLK, /CS, DOUT). Use a ground plane on the layer directly beneath the ADC, and place a single ground-return path under the differential pair to prevent common-mode noise coupling. The external reference bypass (REF+ to GND) should use a 10 µF ceramic in parallel with a 100 nF NP0 capacitor to suppress reference-induced conversion errors.
Do not violate the absolute maximum input voltage on IN+ or IN- of -0.3 V to VDD + 0.3 V; a brief transient above VDD will latch-up the input ESD structure and can permanently damage the part. The /CS pin initiates a sample-and-hold and conversion cycle on its falling edge, so firmware must hold /CS low for the full 16 SCLK cycles to read a complete conversion - releasing /CS mid-cycle aborts the read and returns zero on the next attempt.
Compliance Information
RoHS and REACH compliant per TI product page; Pb-free SOIC-8 package; not AEC-Q100 qualified - choose automotive-grade ADCs for vehicle applications.
