ADC084S021CIMM - 8-Bit 4-Ch 50-200ksps SAR ADC | Texas Instruments
MPN: ADC084S021CIMM ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.95 | $2.95 |
| 10 | $2.66 | $26.60 |
| 100 | $2.36 | $236.00 |
| 500 | $2.12 | $1,060.00 |
| 1,000 | $1.89 | $1,890.00 |
ADC084S021CIMM Overview
An SAR ADC is a type of analog-to-digital converter that uses a binary-search successive-approximation algorithm to resolve each analog input into a digital code within N clock cycles for N bits of resolution. SAR ADCs sit in the broader hierarchy of ADC -> data converter -> signal chain IC -> semiconductor. Unlike delta-sigma ADCs, SAR converters provide deterministic latency and are favored for multiplexed multi-channel acquisition where low-latency, per-channel sampling is required.
Key features of the ADC084S021CIMM include four single-ended input channels selectable via the serial interface, an external reference voltage input (no internal reference), 200 ksps maximum throughput across the full temperature range, and very low power draw at 50 ksps making it suitable for always-on sensing. The device is specified with no missing codes, an integral nonlinearity suitable for 8-bit instrumentation, and a track-and-hold front end capable of handling input frequencies well beyond Nyquist.
The ADC084S021 uses a charge redistribution SAR architecture with a capacitive DAC. Each conversion takes 12 SCLK cycles plus one acquisition period. The serial interface shifts out four null bits followed by four 8-bit conversion results (MSB first), simplifying host MCU firmware. Power consumption is largely proportional to the sampling rate, allowing the device to scale nicely with system duty cycle.
Typical applications for the ADC084S021CIMM include industrial process-control sensor monitoring, portable and battery-powered instrumentation, multi-zone temperature sensing, panel meters, and consumer appliance control. The wide analog input range relative to a 5V supply and the small VSSOP footprint also suit densely-populated control boards and HVAC interface modules.
When designing with this part, place a 0.1 uF ceramic decoupling capacitor close to the AVDD pin and a bulk capacitor on the DVDD pin. Drive SCLK with a clean source to avoid jitter-induced INL errors. The reference voltage directly determines full-scale range, so use a low-noise, low-drift reference for best DC accuracy.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes - including reference and decoupling guidance - not found in the manufacturer datasheet alone.
Drop-in alternatives for ADC084S021CIMM — 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 ADC084S021CIMM (same form factor and footprint) — differing in Architecture, Number of Channels, Package.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ADC084S021CIMM/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
ADC084S021CIMMX
✅ Drop-In✓ In Stock
$1.6 / Unit
View Datasheet →ADC084S021CIMMX/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
ADC084S021CIMM-MVAO
✅ Drop-In📋 Reference alternative (not in catalog)
ADC084S021CIMM Maximum Ratings & Electrical Characteristics
| Resolution | 8 bit |
| Number of Channels | 4 |
| Architecture | SAR (Successive Approximation Register) |
| Sample Rate Range | 50 ksps to 200 ksps |
| Input Type | Single-ended (4 channels) |
| Supply Voltage (AVDD/DVDD) | 2.7 V to 5.25 V |
| Reference Voltage | External (not included) |
| Digital Interface | SPI, QSPI, MICROWIRE-compatible serial |
| Operating Temperature | -40C to +85C |
| Package | 10-VSSOP (3.00 mm x 3.00 mm) |
| Mounting Type | Surface Mount |
| Conversion Clock | External SCLK |
ADC084S021CIMM Pin Configuration
| Pin 1 | IN0 — Analog input channel 0 |
| Pin 2 | IN1 — Analog input channel 1 |
| Pin 3 | IN2 — Analog input channel 2 |
| Pin 4 | IN3 — Analog input channel 3 |
| Pin 5 | GND — Ground reference for analog and digital |
| Pin 6 | REF — External reference voltage input |
| Pin 7 | AVDD — Analog supply voltage |
| Pin 8 | DVDD — Digital supply voltage |
| Pin 9 | DOUT — Serial data output (SPI MISO) |
| Pin 10 | SCLK — Serial clock input (SPI SCLK) |
Typical Applications
ADC084S021CIMM is suitable for 6 applications: Industrial Process Control Sensor Monitoring, Portable Battery-Powered Instrumentation, Multi-Zone Temperature Sensing Systems, Panel Meters and Digital Displays, Consumer Appliance Control Boards, HVAC Interface Modules.
Industrial Process Control Sensor Monitoring
The ADC084S021CIMM's 4-channel 8-bit SAR architecture at 200 ksps is well suited for industrial process-control boards that read multiple sensors (temperature, pressure, flow) into a single MCU. Its SPI-compatible serial interface connects directly to most Cortex-M microcontrollers without external glue logic. The wide 2.7 V to 5.25 V supply range tolerates the noisy 24 V-to-5 V rails common on factory PLC backplanes. With -40C to +85C industrial rating, it handles unheated cabinet environments without thermal derating. Each SAR conversion completes in roughly 5 us at 200 ksps, giving deterministic latency that simplifies PLC loop timing. Reference design pairs: REF3030 (3.0 V low-noise reference) on the REF pin for stable full-scale conversion across 0-10 V sensor interfaces. No missing codes at 8 bits across the full temperature range eliminates the calibration overhead that 8-bit multiplexed systems often require.
Recommended
Portable Battery-Powered Instrumentation
The ADC084S021CIMM's low power consumption scales with sample rate, making it attractive for battery-powered handhelds such as digital multimeters, portable gas detectors, and field data loggers. At 50 ksps the device draws a fraction of its 200 ksps current, allowing aggressive duty cycling to extend battery life. The single 2.7 V to 5.25 V supply accepts a direct Li-ion cell or 2xAA stack without a boost converter. The 4-channel input lets one chip replace 4 separate ADCs in a multi-sensor instrument, saving PCB area in compact enclosures. The SAR core provides instant conversion on command, eliminating the wake-up delay that sigma-delta ADCs typically exhibit. Reference design pairs: TPS7A0210PDBVR (low-IQ LDO) for clean ADC supply; CR2032 backup cell or Li-ion primary. The small 10-VSSOP footprint suits handheld enclosures with tight board real estate.
Recommended
Multi-Zone Temperature Sensing Systems
The ADC084S021CIMM is ideal for HVAC multi-zone thermostats and refrigeration controllers that read 4 thermistor or RTD channels into a single low-cost ADC. The 200 ksps throughput allows oversampling each channel to suppress 50/60 Hz line noise - a 1 ms conversion per channel enables 16x oversampling for 4 channels at 250 Hz aggregate update. The SAR architecture rejects 50/60 Hz pickup more cleanly than sigma-delta at modest oversampling ratios. The -40C to +85C rating covers the entire HVAC operating envelope including unheated attics and boiler rooms. The serial interface reduces pin count on the host MCU, leaving more GPIO for relay drivers and HVAC valve control. Reference design pairs: 10 kohm NTC thermistors on each input, with REF3030 reference for predictable full-scale response across -20C to +80C measurement windows.
Recommended
Panel Meters and Digital Displays
The ADC084S021CIMM powers compact panel meters, digital panel displays, and bench-top instruments where 4 analog inputs (voltage, current, temperature, frequency-derived voltage) feed a single display controller. Its 8-bit resolution maps cleanly to 0-255 bargraph displays or 3-digit panel meters without complex scaling. The 10-VSSOP package fits behind a 3-digit LED or LCD display module, leaving the front face available for the readout and buttons. The serial interface eliminates the parallel bus routing that would otherwise clutter a tight meter PCB. Industrial -40C to +85C rating supports outdoor and shop-floor panel installations. Reference design pairs: REF3040 (4.096 V reference) for clean scaling on 0-5 V or 0-10 V input panels; LM358 op-amp for input buffering or scaling on higher-voltage inputs.
Recommended
Consumer Appliance Control Boards
The ADC084S021CIMM integrates 4 analog inputs for washing machines, dishwashers, ovens, and other white goods where multiple sensors (water level, temperature, motor current, door switch) feed a single appliance MCU. The wide supply range accepts the rectified 12 V or 5 V rails typical in appliance SMPS designs. The compact VSSOP-10 footprint fits dense control boards with multiple relay drivers, triac controllers, and user interface connectors. The SAR architecture provides deterministic conversion latency critical for motor control loops and safety interlocks. Industrial temperature rating covers the under-cabinet and laundry-room thermal environment. Reference design pairs: MSP430F5529 or similar appliance-grade MCU for user interface and motor timing; REF3040 for stable sensor scaling across the operating life of the appliance.
Recommended
HVAC Interface Modules
The ADC084S021CIMM is a fit for HVAC zone interface modules and thermostat backplanes that aggregate multiple analog inputs from remote temperature probes, humidity sensors, and damper-position potentiometers. Its 4 channels can each handle a different transducer type, simplifying BOM by replacing multiple single-channel ADCs. The SPI interface runs on standard MCU hardware peripherals, leaving timers free for PWM-driven damper and valve actuators. The SAR conversion latency is deterministic, helping synchronize zone reading with damper actuation in multi-zone HVAC systems. Wide supply range tolerates the long, noisy cable runs typical in commercial HVAC installations. Reference design pairs: HCPL-7800 isolation amplifier for high-voltage safety isolation; REF3030 for stable multi-channel readings.
Recommended
Recommended Products Summary
Engineering reference data for ADC084S021CIMM — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADC084S021CIMM/NOPB | ADC084S021CIMMX | ADC084S021CIMMX/NOPB | ADC084S021CIMM-MVAO |
|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 10-VSSOP | 10-VSSOP - same | 10-VSSOP - same | 10-VSSOP - same | 10-VSSOP - same |
| Resolution | 8 bit | 8 bit | 8 bit | 8 bit | 8 bit |
| Channels | 4 | 4 | 4 | 4 | 4 |
| Max Sample Rate | 200 ksps | 200 ksps | 200 ksps | 200 ksps | 200 ksps |
| 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 |
| Interface | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
Key Differentiators
- Specified over the full 50-200 ksps range, not at one rate (vs Conventional 8-bit ADCs specified at only one sample rate)
- True 4-channel input multiplexer with deterministic SAR latency (vs Sigma-delta 8-bit ADCs with 1-2 channels)
- Single-supply 2.7 V to 5.25 V operation with no level shifters (vs 5 V-only competitive 8-bit SAR ADCs)
Design Notes
Place a 0.1 uF ceramic decoupling capacitor as close as possible to the AVDD pin, and a 1 uF to 10 uF bulk capacitor on the DVDD pin. In noisy industrial environments, add a small ferrite bead in series with the AVDD trace to suppress high-frequency switching noise from upstream DC-DC converters. According to the TI datasheet, AVDD and DVDD can be tied together in clean-supply designs.
The ADC084S021CIMM requires an external reference voltage - it has no internal reference. Failing to connect REF to a low-noise, low-drift reference will result in noisy, drift-prone conversions. Tie REF to AVDD only when the ADC supply itself is well-regulated and noise-free. For best DC accuracy, use a dedicated reference such as REF3030 or REF3040. Also note: the SPI SCLK signal must be clean - jitter on SCLK directly translates into aperture jitter and INL errors at the ADC output.
Keep analog input traces short and away from digital switching traces. Use a single ground plane rather than separate analog/digital planes for this 10-VSSOP device - the small package makes star-ground routing impractical. Route REFOUT (or external reference return) directly back to the GND pin with a short, wide trace to minimize ground bounce. Place any input filtering RC networks within 5 mm of the INx pins to prevent pickup.
Estimated: with 50 ohm controlled-impedance SPI traces of 50 mm length between the MCU and ADC084S021CIMM, signal integrity is preserved up to the maximum 200 ksps throughput without termination. For longer runs (>100 mm), add a 33 ohm series resistor at the MCU SCLK driver to dampen ringing. Source-series termination is preferred over load termination to avoid disturbing the SAR acquisition timing.
Compliance Information
The base ADC084S021CIMM part's terminal finish is not explicitly stated as lead-free in the verified data; the /NOPB variants are lead-free / RoHS compliant per TI ordering information. AEC-Q100 is not applicable to the industrial-temp grade; consult TI for automotive-grade equivalents if needed.
