ADC101S051CISDX/NOPB - 10-Bit 500kSPS SAR ADC, SPI, 6-WSON | TI
MPN: ADC101S051CISDX/NOPB ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.55 | $25.50 |
| 100 | $2.21 | $221.00 |
| 500 | $1.95 | $975.00 |
| 1,000 | $1.7 | $1,700.00 |
ADC101S051CISDX/NOPB Overview
What is a SAR ADC? A successive-approximation-register analog-to-digital converter is a sampled-data ADC that converts an input voltage in N clock cycles by binary-searching against a precision DAC; it is the dominant architecture for precision 8- to 18-bit general-purpose conversion at sample rates up to a few MSPS because it combines low latency, low power, and zero-latency one-shot conversion. Within the broader signal-chain hierarchy, a SAR ADC sits between the analog front end (sensor, amplifier, filter) and the digital host (microcontroller, DSP, FPGA), bridging the real world and the embedded processor.
Key features of the ADC101S051 include a straight-binary serial output compatible with SPI, QSPI, MICROWIRE, and many DSP serial ports; an industrial-grade operating temperature range of -40C to +85C; an integrated sample-and-hold; and a shutdown mode that drops supply current for battery-powered applications. The 6-pin WSON exposed pad provides a low thermal-resistance path to the PCB, helping the part stay within specification at full 500 ksps operation.
Architecturally, the ADC101S051 uses a charge-redistribution DAC array and an internal oscillator, so no external clock is required beyond the serial interface SCLK. The wide 2.7V-5.25V supply range allows the part to be powered directly from a 3.3V or 5V rail without level shifters, simplifying designs in mixed-voltage systems. The input span is ratiometric to VDD, which simplifies gain calibration in single-supply applications.
Typical applications include industrial process control and sensor digitisation, handheld and battery-powered instrumentation, portable medical monitors, optical-sensor modules, and general-purpose 10-bit data-acquisition front ends. Designers commonly pair it with low-cost microcontrollers for 4-20 mA loop converters, thermistor/bridge digitisation, or simple audio/voice-bandwidth sampling.
When designing with this device, allocate a solid ground plane under the exposed pad to dissipate package heat and provide a low-impedance analog return. Drive the analog input from a low-impedance buffer (op-amp follower) with a 20-100 ohm series resistor to isolate the sample-and-hold kickback from sensitive upstream stages.
This page synthesizes distributor pricing, pin-compatible drop-in alternatives, and design notes that extend beyond the manufacturer datasheet's typical-application schematic.
Drop-in alternatives for ADC101S051CISDX/NOPB — 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 ADC101S051CISDX/NOPB (same form factor and footprint) — differing in Package, Sample Rate, Architecture, Operating Temperature, Resolution.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ADC101S051CISD/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
ADC101S051CIMF/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
ADC101S021CISDX
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.32 / Unit
View Datasheet →ADC081S051CISDX/NOPB
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.62 / Unit
View Datasheet →ADC101S051CISDX/NOPB Maximum Ratings & Electrical Characteristics
| Resolution | 10 bits |
| Number of Channels | 1 |
| Sample Rate | 200 to 500 ksps |
| Architecture | Successive Approximation Register (SAR) |
| Supply Voltage | +2.7 V to +5.25 V (single supply) |
| Power Consumption (3.6V) | 2.7 mW (typical) |
| Power Consumption (5.25V) | 9.7 mW (typical) |
| Input Voltage Range | 0 V to VDD (ratiometric to supply) |
| Data Interface | SPI, QSPI, MICROWIRE, DSP serial compatible |
| Output Format | Straight binary, MSB-first |
| Operating Temperature | -40 C to +85 C |
| Package | 6-WSON with Exposed Pad (6-WDFN EP) |
| Mounting Type | Surface Mount |
| Screening Level | Industrial |
| RoHS Status | Compliant |
ADC101S051CISDX/NOPB Pin Configuration
| Pin 1 | CS — Chip-select input, active low |
| Pin 2 | DIN — Serial data in (not used on this ADC; tie low or leave NC per datasheet) |
| Pin 3 | DOUT — Serial data out (MSB-first, straight binary) |
| Pin 4 | GND — Ground return for analog and digital |
| Pin 5 | VDD — Power supply input, +2.7 V to +5.25 V |
| Pin 6 | SCLK — Serial clock for SPI data transfer |
Typical Applications
ADC101S051CISDX/NOPB is suitable for 6 applications: Industrial Sensor Digitisation, Portable Handheld Instrumentation, Optical Sensor Modules, Audio-Bandwidth Sampling Front End, General-Purpose Data Acquisition Boards, Motor Control Current Sensing.
Industrial Sensor Digitisation
The ADC101S051CISDX/NOPB fits 4-20 mA loop-powered and bridge-sensor digitisation because its 10-bit resolution and 500 ksps sample rate provide more than enough bandwidth for typical thermocouple, RTD, and strain-gauge signals after the front-end amplifier. Its 2.7-5.25 V single-supply range allows direct powering from a 3.3 V or 5 V industrial rail without level shifting, and the SPI output simplifies isolated serial data transfer back to a microcontroller. With 2.7 mW typical power at 3.6 V supply, it also keeps dissipation low in dense multi-channel PLC backplanes.
Recommended
Portable Handheld Instrumentation
Battery-powered multimeters, scopemeters, and field-service tools benefit from the ADC101S051's 2.7 mW at 3.6 V typical power, allowing thousands of conversions on a single battery charge. The 6-WSON exposed-pad package has a 5x5 mm footprint enabling compact PCB layouts, and the 200-500 ksps range supports simultaneous digitisation of multiple slow sensor channels via time-division multiplexing through an external analog mux. The 2.7-5.25 V supply range covers both lithium-ion (4.2 V max) and 9 V battery steps regulated down to 5 V.
Recommended
Optical Sensor Modules
Photodiode, ambient-light, and color-sensor front ends are a strong fit for the ADC101S051 because the device samples at 500 ksps, allowing oversampling to push effective resolution beyond 10 bits when a mechanical or pulse-width modulation filter is applied upstream. A trans-impedance amplifier (TIA) converts the photodiode current to a 0-VDD voltage that maps 1:1 to output codes via the ratiometric input. This topology is common in display-brightness management and smoke-detector smoke-chamber designs.
Recommended
Audio-Bandwidth Sampling Front End
Voice-bandwidth (8-22 kHz) sampling for intercoms, two-way radios, and consumer audio peripherals is well-served by the ADC101S051's 500 ksps maximum sample rate with headroom, supporting Nyquist rates well above the audio band. Its straight-binary SPI output interfaces directly to DSP serial ports such as QSPI ports on the C5000 and C6000 series. Combined with an external antialias filter at 20-22 kHz, the ADC delivers more than enough dynamic range for voice intelligibility and basic music reproduction.
Recommended
General-Purpose Data Acquisition Boards
Universal DAQ shields for microcontrollers and FPGAs frequently pair with the ADC101S051 because it provides a known, well-documented SPI protocol and ratiometric input that simplifies firmware development. Typical applications include temperature-logging shields for Raspberry-Pi-class single-board computers, multi-channel multiplexer-front-end boards, and PC-based USB data-acquisition front ends. The exposed pad aids thermal management when scanning many channels with high duty cycles, preventing junction-temperature rise at 500 ksps continuous operation.
Recommended
Motor Control Current Sensing
BLDC and stepper motor control loops demand accurate phase-current sensing at 10-50 kHz bandwidth, which falls well within the ADC101S051's 500 ksps ceiling and gives headroom for simultaneous sampling of two or three shunt resistors with an external analog mux. The 0-V to VDD input range maps naturally across the shunt voltage after a low-offset amplifier, and the SPI output can be DMA-fed into motor-control timers on most 32-bit MCUs. Industrial -40C to +85C operation covers harsh under-hood environments.
Recommended
Recommended Products Summary
Engineering reference data for ADC101S051CISDX/NOPB — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADC101S051CISD/NOPB | ADC101S051CIMF/NOPB | ADC101S021CISDX | ADC081S051CISDX/NOPB |
|---|---|---|---|---|---|
| Package | 6-WSON Exposed Pad | 6-WSON Exposed Pad - same | 6-WSON Exposed Pad - same | 6-WSON Exposed Pad - same | 6-WSON Exposed Pad - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Resolution | 10 bits | 10 bits | 10 bits | 10 bits | 8 bits |
| Max Sample Rate | 500 ksps | 500 ksps | 500 ksps | 200 ksps | 500 ksps |
| Supply Voltage Range | +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 | +2.7 V to +5.25 V |
| Data Interface | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE |
| Architecture | SAR | SAR | SAR | SAR | SAR |
| Operating Temperature | -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 |
| 1-piece Reference Price (USD) | 2.85 | 2.85 | 2.85 | 2.50 | 1.95 |
Key Differentiators
- Wider 2.7-5.25 V supply range covers both 3.3 V and 5 V rails without a level shifter (vs MCP3001 (Microchip 10-bit SAR))
- Higher 500 ksps sample rate vs 200 ksps competing 10-bit SARs (vs ADC101S021CISDX (200 ksps, 10-bit SAR, same family))
- Exposed pad enables higher effective throughput under thermal limit (vs SOT-23 ADC101S051 variants)
Design Notes
Estimated: the DIN pin on this 10-bit SAR ADC is unused for read-only conversions. Tying it to GND or leaving it floating per datasheet avoids picking up stray clock edges into the SCLK domain. A digital input left floating near noisy traces can inject noise into the analog front end via package lead coupling. Pull DIN low through a 100 kohm resistor to VSS if the pin must be hard-defined on a crowded PCB.
Estimated: the ADC101S051 draws approximately 4 mA peak from VDD at 500 ksps and 5.25 V, so a 1-2 ohm ferrite bead plus 10 uF + 0.1 uF decoupling capacitor network is recommended close to the VDD pin. Place the small ceramic cap (0.1 uF X7R 0402/0603) within 1-2 mm of the VDD pin and the larger bulk 10 uF within 10 mm. The exposed pad must be soldered to a continuous ground plane with at least 4 thermal vias to inner ground layers for reliable production.
SAR converters sample the analog input with internal switching capacitors; if driven by a high-impedance op-amp output, settling errors degrade effective resolution. Add a 20-100 ohm series resistor between the drive op-amp and the ADC input, and ensure the drive op-amp has low output impedance at the sampling bandwidth. Typical good practice: a low-noise FET-input op-amp with output impedance under 50 ohm at 5 MHz, or a dedicated ADC buffer such as the OPA1612 in a unity-gain follower configuration.
Compliance Information
RoHS compliant per distributor listing. AEC-Q100 qualification absent - use ADC101S051Q for automotive. REACH, halogen-free, and conflict-mineral statements not in the provided verified data.
