ADC121S101CISDX/NOPB - 12-Bit 1Msps Single-Channel SAR ADC | TI
Référence : ADC121S101CISDX/NOPB ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $2.85 | $2,85 |
| 10 | $2.58 | $25,80 |
| 100 | $2.21 | $221,00 |
| 500 | $1.94 | $970,00 |
| 1 000 | $1.67 | $1 670,00 |
| 4 500 | $1.42 | $6 390,00 |
ADC121S101CISDX/NOPB Présentation
A SAR ADC is a successive-approximation analog-to-digital converter that resolves one bit per clock cycle using a binary-search algorithm against the held input voltage. In the broader data-converter hierarchy, SAR ADCs sit between flash converters (fastest, lowest resolution) and sigma-delta ADCs (slowest, highest resolution), and they are the workhorse choice for general-purpose 8-14 bit, 100 ksps-10 Msps applications where deterministic latency, low power, and small package footprint are all required. The ADC121S101 family is one of TI's lowest-power members of that family.
Key features include a hardware-configurable SCLK speed (auto-detected at power-up), a SPI/QSPI/MICROWIRE-compatible serial interface, true-differential analog input, and an integral non-linearity typically within ±0.5 LSB. A power-down pin reduces supply current to a few microamps between conversions, which is critical for duty-cycled battery-powered systems. Housed in a 6-lead WSON (also available in SOT-23 in the family), it occupies a footprint that fits beneath or beside many microcontrollers on a two-layer PCB.
The converter uses a charge-redistribution DAC array with an inherent track-and-hold front end, supporting input bandwidth sufficient for sensor signals in the kHz range and a throughput of up to one million 12-bit words per second. Compared with the more common 8-/12-bit MCU-integrated ADCs, the ADC121S101 separates the analog reference (REF taken from VDD) from noisy digital supplies and provides a deterministic 16-clock conversion cycle, simplifying DMA-based timing in microcontroller firmware.
Typical applications include portable instrumentation and handheld meters, automotive sensor readback, industrial process-control analog front ends, consumer audio level metering, optical-sensor signal conditioning, and general-purpose data-acquisition boards. Any mixed-signal system that needs one to a few channels of accurate, low-power DC measurement with a small footprint is a candidate.
When designing with this device, place the 0.1 µF VDD decoupling capacitor within a few millimetres of the pin and keep the analog input trace short and guarded by a ground pour. Do not multiplex the analog input without a hold capacitor in front of the ADC, because the SAR architecture samples the signal at a single instant rather than continuously tracking it.
This page synthesizes distributor pricing, drop-in and reel-code alternatives, and engineering guidance drawn from the manufacturer datasheet and reference designs - information you will not find on a single OEM product page or generic catalog listing.
Alternatives de remplacement direct pour ADC121S101CISDX/NOPB — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Variantes de cette série
Modèles de la même série directement compatibles avec ADC121S101CISDX/NOPB (même facteur de forme et même empreinte) — différant par Package, Operating Temperature, Architecture, Resolution, RoHS Status.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
ADC121S101CISD/NOPB
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
ADC121S101CIMFX/NOPB
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
ADC121S101CIMFX
✅ Remplacement direct ⚠️ Spécifications non vérifiées✓ En stock
$1.85 / unité
Voir la fiche technique →ADC121S051CIMFX
✅ Remplacement direct✓ En stock
$1.95 / unité
Voir la fiche technique →ADC121S021CISDX
✅ Remplacement direct✓ En stock
$1.85 / unité
Voir la fiche technique →ADC121S021CISD
✅ Remplacement direct ⚠️ Spécifications non vérifiées✓ En stock
$1.79 / unité
Voir la fiche technique →ADC102S101CIMMX/NOPB
✅ Remplacement direct✓ En stock
$2.1 / unité
Voir la fiche technique →ADC121S101CISDX/NOPB Valeurs maximales et caractéristiques électriques
| Résolution | 12 bit |
| Number of Channels | 1 |
| Sample Rate Range | 500 ksps to 1 Msps |
| Architecture | SAR (Successive Approximation) |
| Supply Voltage (VDD) | 2.7 V to 5.25 V |
| Analog Input Type | Single-ended (true-differential input pin pair) |
| Tension de référence | VDD (internal, no external reference) |
| Serial Interface | SPI / QSPI / MICROWIRE compatible |
| SCLK Frequency | Up to 20 MHz (auto-detected) |
| Conversion Cycles | 16 SCLK cycles per conversion |
| Plage de température de fonctionnement | -40C to +125C |
| Boîtier | 6-pin WSON (2.2 x 2.5 mm) |
| Type de montage | Surface Mount |
| Power-Down Current | As low as 2.6 uW at 5 V supply |
| Statut RoHS | Compliant (NOPB = No Pb, lead-free) |
| Packaging Format | Tape and Reel (X suffix, 4500 pcs standard) |
Configuration des broches de ADC121S101CISDX/NOPB
| Broche 1 | VIN+ — Positive analog input |
| Broche 2 | GND — Ground |
| Broche 3 | VDD — Power supply (2.7 V to 5.25 V) |
| Broche 4 | SCLK — Serial clock input (auto-detected up to 20 MHz) |
| Broche 5 | DOUT — Serial data output |
| Broche 6 | CS — Chip select (active low) |
| Broche 7 | EP — Exposed thermal pad (grounded to GND) |
Applications typiques
ADC121S101CISDX/NOPB convient pour 6 applications: Portable Handheld Battery Test, Automotive Sensor Readback, Industrial Process Control Front End, Optical Sensor Signal Conditioning, Consumer Audio Level Metering, General-Purpose Data Acquisition Module.
Portable Handheld Battery Test
The ADC121S101CISDX/NOPB is well suited to portable handheld instruments where battery voltage drops from 4.2 V to 2.7 V during the measurement session. Its 2.7 V-5.25 V single-supply operation eliminates the need for a boost regulator, and the 2.6 uW power-down current allows duty-cycled operation. The 6-pin WSON (2.2x2.5 mm) footprint occupies less than 6 mm^2 of PCB area, leaving room for a battery, an op-amp front end, and a small microcontroller in a typical multimeter or sensor module form factor. Compared with a microcontrollers internal ADC, the dedicated SAR architecture maintains 12-bit linearity across the full -40C to +125C operating range.
Recommandé
Automotive Sensor Readback
The ADC121S101CISDX/NOPB operates from -40C to +125C, matching the temperature grade required for many automotive sensor modules such as battery management current shunts, tire pressure sensor transponders, and HVAC position feedback. The SAR architecture provides deterministic 16-SCLK-cycle conversion latency, simplifying timing for ECU firmware that synchronizes ADC readings with sensor excitation. The exposed thermal pad supports ground-return integrity in noisy automotive environments where switching EMI from motors and relays can couple into unshielded aerodynamics.
Recommandé
Industrial Process Control Front End
The ADC121S101CISDX/NOPB provides 12-bit resolution and 1 Msps throughput for industrial 4-20 mA loop converters, RTD temperature bridges, and strain-gauge signal chains. Its high-speed SPI interface supports up to 20 MHz SCLK, enabling multi-channel modules where several ADC121S101X chips are daisy-chained on a single SPI bus for parallel sampling. The single 2.7-5.25 V supply aligns with 24V-to-5V industrial backplanes. The exposed thermal pad helps dissipate the small but non-zero switching losses in high-density PLC modules that house dozens of these converters.
Recommandé
Optical Sensor Signal Conditioning
The ADC121S101CISDX/NOPB digitizes photodiode, phototransistor, and color-sensor analog outputs in ambient-light meters and optical encoder modules. Its 1 Msps sample rate captures transient events such as LED pulse modulation and fast-changing ambient illumination profiles in industrial light curtains. The internal sample-and-hold captures a single snapshot of the signal, eliminating timing skew between channels when paired with a multi-channel companion ADC. Power consumption of 2.6 uW in shutdown mode allows battery-powered optical designs to wake briefly, sample, and return to sleep.
Recommandé
Consumer Audio Level Metering
The ADC121S101CISDX/NOPB digitizes audio envelope signals from rectifier or RMS-detection front ends in VU meters, peak indicators, and consumer audio mixers. The 500 ksps-1 Msps sample rate comfortably oversamples the audio band at 8 kHz, capturing fast peaks without aliasing. The SPI interface avoids contention with the audio codec I2S bus on the host processor. The tiny 6-pin WSON (2.2 x 2.5 mm) footprint enables front-panel modules behind a slim LCD display. Low power consumption suits battery-powered portable PA mixers.
Recommandé
General-Purpose Data Acquisition Module
The ADC121S101CISDX/NOPB serves as a foundational single-channel digitizer for bench-top and embedded data-acquisition modules. Each converter costs approximately $1.42 at full-reel volume, making it cost-effective for multi-channel modules that aggregate 8, 16, or 32 channels of measurement behind a single FPGA or microcontroller. The auto-detected SCLK eliminates firmware-side clock-divider configuration when changing sample rates, and the SPI daisy-chain capability allows several ADCs to share one chip-select pin across many channels. The exposed thermal pad supports stable operation at full 1 Msps continuous sampling across telemetry.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour ADC121S101CISDX/NOPB — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | ADC121S101CISD/NOPB | ADC121S101CIMFX/NOPB | ADC121S101CIMF | ADC121S051CIMFX | ADC121S021CISDX | ADC102S101CIMMX/NOPB |
|---|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | WSON-6 (2.2 x 2.5 mm) | WSON-6 (2.2 x 2.5 mm) - same | SOT-23-6 - same pinout | SOT-23-6 - same pinout | SOT-23-6 - same pinout | WSON-6 (2.2 x 2.5 mm) - same | MSOP-8 - same family, MSOP-8 (dual-channel) |
| Resolution | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit | 12 bit |
| Sample Rate | 500 ksps to 1 Msps | 500 ksps to 1 Msps | 500 ksps to 1 Msps | 500 ksps to 1 Msps | 500 ksps to 1 Msps | 50 to 200 ksps (20% of original) | 500 ksps to 1 Msps |
| Number of Channels | 1 | 1 | 1 | 1 | 1 | 1 | 2 (dual-channel) |
| Supply Voltage | 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 | 2.7 V to 5.25 V | 2.7 V to 5.25 V |
| Interface | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE |
| Operating Temperature | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +125C | -40C to +125C |
| Lead-Free / RoHS | Yes (NOPB) | Yes (NOPB) | Yes (NOPB) | Cut-tape only | Yes (NOPB) | Yes | Yes (NOPB) |
Principaux différenciateurs
- True 12-bit linearity across 500 ksps-1 Msps, not just at a single sample rate (vs ADC121S021CISDX (50-200 ksps, 20% throughput))
- WSON-6 (2.2 x 2.5 mm) ultra-compact package option vs SOT-23-6 (vs ADC121S101CIMFX/NOPB (SOT-23-6))
- Single-channel simplicity with no auxiliary reference required (vs ADC102S101CIMMX/NOPB (dual-channel, MSOP-8))
Notes de conception
Place a 0.1 uF ceramic decoupling capacitor within 2-3 mm of the VDD pin (pin 3) and a bulk 1-10 uF tantalum or ceramic capacitor at the chip supply node. According to the TI datasheet, the VDD supply also serves as the ADC reference, so any noise on this rail directly degrades SNR. In mixed-signal layouts, route the analog VDD through a ferrite bead and a local low-dropout LDO to isolate digital switching noise. Decouple the exposed thermal pad (pin 7) to the analog ground pour with multiple vias to provide a low-impedance ground return.
Route the analog input (VIN+, pin 1) as a short, guarded trace with ground fill on both sides, and keep it away from digital signal traces (SCLK, DOUT, CS) to minimize capacitive coupling. According to the TI datasheet, the SAR architecture samples the analog input on a single clock edge, so any noise present at that instant appears as a conversion error. Do not route the analog input through a multiplexer without a hold capacitor in front of the ADC - the multiplexer switching transients would couple directly into the sampled voltage.
Do not operate the ADC121S101CISDX/NOPB above 5.25 V - this is the absolute maximum and will damage the device. Ensure CS is held high between conversions to enter power-down mode; otherwise the device will continuously draw several mA. According to the TI datasheet, the SCLK must idle low between conversions to ensure proper startup behavior. When using multiple ADCs on a shared SPI bus, ensure that the inactive devices have CS held high to avoid bus contention on DOUT.
Informations de conformité
The /NOPB suffix indicates lead-free, RoHS-compliant assembly per TI's ordering guide. The part is not AEC-Q100 qualified - for safety-critical automotive ADAS applications, consider AEC-Q100-qualified variants. Halogen-free per TI's standard package materials.
