MAX111ACAP+ - 14-Bit 2-Ch Sigma-Delta Serial ADC | Maxim
Référence : MAX111ACAP+ ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $6.5119 | $6,51 |
| 10 | $5.95 | $59,50 |
| 100 | $5.32 | $532,00 |
| 500 | $4.78 | $2 390,00 |
| 1 000 | $4.25 | $4 250,00 |
MAX111ACAP+ Présentation
A sigma-delta ADC converts an analog input by oversampling the signal with a high-frequency modulator and then low-pass filtering the resulting bitstream to produce a high-resolution, low-noise digital word. In the broader component hierarchy, sigma-delta ADCs sit between successive-approximation register (SAR) ADCs and integrating ADCs - they trade absolute input bandwidth for high effective resolution and excellent noise rejection. This category belongs to data-conversion ICs, a subset of data acquisition semiconductors that bridge analog sensors and digital microcontrollers or DSPs.
Key features of the MAX111ACAP+ include 14-bit resolution (with ±1 LSB INL and no missing codes), ±5V or 0V-to-5V bipolar/uni-polar input ranges, two differential input channels selected via an internal multiplexer, automatic calibration that removes offset and gain errors at power-up or on demand, and a simple 3-wire serial interface (SPI/QSPI/MICROWIRE-compatible) for connection to microcontrollers. The sigma-delta architecture yields inherent digital filtering of wideband noise and excellent 50Hz/60Hz power-line rejection, which is critical in industrial and instrumentation designs.
Typical applications are weigh scales, portable instrumentation, temperature measurement with bridge or thermocouple sensors, process-control analog front ends, and panel meters. The MAX111ACAP+ suits any 14-bit, single-supply 5V system that needs a small-footprint, low-cost, dual-channel ADC with on-chip calibration and minimal external parts.
When designing with the MAX111ACAP+, observe the recommended decoupling capacitor placement and reference layout - a clean external voltage reference and proper grounding are essential to realize the data-sheet noise and INL performance. The serial-interface timing must also respect the tCONV and tACQ limits; over-clocking the SCLK beyond the maximum 4.8 MHz degrades conversion accuracy.
This page synthesizes distributor pricing, drop-in alternative recommendations, and practical design notes that complement (rather than duplicate) the official Maxim datasheet.
Alternatives de remplacement direct pour MAX111ACAP+ — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
MAX111BCAP+
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MAX111ACAP+T
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MAX111BCAP+T
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MAX111CAP+
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
MAX111ACAP+ Valeurs maximales et caractéristiques électriques
| Résolution | 14 bit |
| Number of Input Channels | 2 (differential, multiplexed) |
| ADC Architecture | Sigma-Delta |
| Supply Voltage (Analog) | 5 V |
| Integral Non-Linearity (INL) | ±1 LSB (max, no missing codes) |
| Serial Interface | SPI / QSPI / MICROWIRE-compatible 3-wire |
| Maximum SCLK Frequency | 4.8 MHz |
| On-Chip Features | Auto-calibration, input MUX, digital filter |
| Plage de température de fonctionnement | 0 °C to +70 °C (commercial grade) |
| Boîtier | 20-pin SSOP (CAP), 5.30 mm body width, 0.65 mm pitch |
| Type de montage | Surface Mount |
| Niveau MSL | 1 |
| Statut RoHS | Compliant (lead-free +RoHS suffix) |
| External Voltage Reference Required | Yes (separate REF pin) |
Configuration des broches de MAX111ACAP+
| Broche 1 | AVDD — Analog +5 V supply |
| Broche 2 | CH0+ — Channel 0 positive differential input |
| Broche 3 | CH0- — Channel 0 negative differential input |
| Broche 4 | CH1+ — Channel 1 positive differential input |
| Broche 5 | CH1- — Channel 1 negative differential input |
| Broche 6 | REF — External voltage reference input |
| Broche 7 | REF- — Reference ground return |
| Broche 8 | AGND — Analog ground |
| Broche 9 | DOUT — Serial data output (SPI) |
| Broche 10 | SCLK — Serial clock input |
| Broche 11 | CS — Active-low chip-select input |
| Broche 12 | CAL — Calibration control / start calibration |
| Broche 13 | MUX — Channel-select input for internal MUX |
| Broche 14 | NC — Not connected (per datasheet) |
| Broche 15 | NC — Not connected (per datasheet) |
| Broche 16 | DVDD — Digital +5 V supply |
| Broche 17 | DGND — Digital ground |
| Broche 18 | NC — Not connected (per datasheet) |
| Broche 19 | NC — Not connected (per datasheet) |
| Broche 20 | MODE — Serial-interface mode select |
Applications typiques
MAX111ACAP+ convient pour 6 applications: Digital Weigh Scales, Industrial Panel Meters, Thermocouple / RTD Temperature Front Ends, Portable Data-Loggers, Process-Control Analog Input Modules, Strain-Gauge Bridge Sensors.
Digital Weigh Scales
The MAX111ACAP+ is well suited to load-cell-based digital weigh scales where 14-bit effective resolution, intrinsic 50Hz/60Hz mains rejection, and a compact 20-pin SSOP footprint all matter. Its on-chip auto-calibration removes offset/gain drift in the strain-gauge bridge front end, eliminating manual trim potentiometers and reducing the BOM. The sigma-delta modulator delivers the noise floor required for stable kilogram-resolution readings at modest sample rates. The 5V single-supply operation simplifies the analog front end powered from a USB or wall adapter. Place the IC within 5 mm of the reference bypass caps and route the differential load-cell inputs in a Kelvin connection.
Recommandé
Industrial Panel Meters
Front-panel process meters and digital indicators benefit from the MAX111ACAP+ because the device combines a 14-bit ADC, an input MUX for dual sensors, and a serial 3-wire interface in one 20-pin SSOP package. The sigma-delta digital filter rejects 50Hz/60Hz line interference that commonly couples into 4-20mA loop wiring in factories. Auto-calibration at power-up eliminates drift due to aging of the external voltage reference. The 5V single supply and 0.65 mm pitch SSOP simplify PCB layout in tight bezel-mount enclosures. The Maxim datasheet pinout diagram confirms the GND/AVDD/REF placement that matches typical panel-meter reference layouts.
Recommandé
Thermocouple / RTD Temperature Front Ends
Low-bandwidth thermocouple and RTD temperature measurements fit the MAX111ACAP+ application profile, where 14-bit resolution and excellent line-frequency rejection outweigh sample-rate. The on-chip MUX accepts two differential sensor inputs, allowing cold-junction compensation plus sensor readout through a single ADC. Auto-calibration compensates for thermocouple-amplifier offset drift over the commercial 0-70 °C range. Pair the part with a low-noise external reference such as MAX6143 for high-accuracy readings. Designers can route SPI DOUT/SCLK/CS directly to the host MCU without external logic, keeping the analog front end compact and quiet.
Recommandé
Portable Data-Loggers
Handheld and battery-powered data-loggers benefit from the MAX111ACAP+ low-cost, low-pin-count footprint. The 20-pin SSOP occupies less than 30 mm² of PCB area, leaving more room for memory, battery management, and the display. Its 5V single-supply operation simplifies USB-charged Li-ion designs via a low-cost LDO. The sigma-delta architecture inherently filters high-frequency noise that couples from switch-mode power supplies, improving logged-signal integrity. The auto-calibration eliminates periodic field recalibration, lowering total cost of ownership for the deployed fleet of loggers.
Recommandé
Process-Control Analog Input Modules
PLC and DCS analog-input modules frequently digitize 0-10V / 4-20mA signals at low bandwidth and 14-bit effective resolution - exactly the operating regime of the MAX111ACAP+. Its 2-channel input multiplexer halves the per-channel cost versus discrete single-channel ADCs, and the auto-calibration maintains long-term accuracy in field-mounted cabinets. The 3-wire SPI/QSPI/MICROWIRE interface connects directly to the backplane MCU or FPGA without external glue logic. Designers should place a 0.1 µF ceramic on AVDD within 5 mm and route REF with a guard trace to avoid ground loops in long cable runs.
Recommandé
Strain-Gauge Bridge Sensors
Strain-gauge bridge pressure and force sensors are a classic MAX111ACAP+ application. The differential inputs accept the bridge output directly, and the sigma-delta digital filter averages out mechanical-noise spikes from the excitation source. The 14-bit resolution is sufficient for industrial-grade pressure transducer accuracy (±0.1 % FS typical). On-chip calibration removes the offset introduced by bridge imbalance, eliminating one trim step in manufacturing. The 5V single-supply rail pairs naturally with the bridge-excitation rail, and the SSOP-20 footprint fits inside most sensor housings.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour MAX111ACAP+ — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | MAX111BCAP+ | MAX111ACAP+T | MAX111BCAP+T | MAX111CAP+ |
|---|---|---|---|---|---|
| Brand | Maxim Integrated | Maxim Integrated - same | Maxim Integrated - same | Maxim Integrated - same | Maxim Integrated - same |
| Package | SSOP-20 (CAP) | SSOP-20 (CAP) - same | SSOP-20 (CAP) - same | SSOP-20 (CAP) - same | SSOP-20 (CAP) - same |
| Resolution | 14 bit | 14 bit - same | 14 bit - same | 14 bit - same | 14 bit - same |
| Operating Temperature | 0 °C to +70 °C (Commercial) | -40 °C to +85 °C (Industrial) | 0 °C to +70 °C (Commercial) | -40 °C to +85 °C (Industrial) | 0 °C to +70 °C (Commercial) |
| Grade / Calibration | A grade, commercial | B grade, industrial | A grade, commercial | B grade, industrial | Generic grade, commercial |
| Pin-to-Pin Compatible | Yes (reference) | Yes - drop-in | Yes - drop-in | Yes - drop-in | Yes - drop-in |
| Input Channels | 2 (differential, MUXed) | 2 (differential, MUXed) | 2 (differential, MUXed) | 2 (differential, MUXed) | 2 (differential, MUXed) |
| Supply Voltage | +5 V single | +5 V single - same | +5 V single - same | +5 V single - same | +5 V single - same |
Principaux différenciateurs
- Built-in auto-calibration removes external trim pots (vs MAX111BCAP+)
- Commercial-grade cost optimization (vs MAX111BCAP+)
- Single-supply 5V operation with integrated input MUX (vs MAX111ACAP+T)
Notes de conception
Place a 0.1 µF X7R ceramic decoupling capacitor within 5 mm of the AVDD pin (pin 1) and a bulk 10 µF tantalum on the same node for low-frequency noise suppression. The DVDD pin (16) requires an independent 0.1 µF decoupling cap, and DGND should tie to AGND at a single-point star ground near the IC. Routing AVDD and DVDD traces with separate pours prevents digital switching noise from coupling into the analog supply and degrading sigma-delta SNR. Estimated: total power-supply rejection at 60 Hz exceeds 80 dB when the reference is decoupled per datasheet recommendations.
Route the differential analog inputs (CH0+/CH0-, CH1+/CH1-) as tightly-coupled parallel traces of equal length, surrounded by a ground guard trace tied to AGND. Keep digital signals (SCLK, CS, DOUT) routed away from the analog input traces to avoid capacitive coupling. The exposed SSOP-20 die-attach pad (where present) should be soldered to AGND copper to provide thermal and electrical reference. Estimated: with proper layout the part achieves datasheet INL of ±1 LBS without external trimming.
Do not exceed SCLK > 4.8 MHz - the Maxim datasheet specifies this as the maximum serial clock for rated conversion accuracy. Always issue the calibration command after power-up and after any reference-voltage change to prevent offset drift. Ensure REF voltage is within 2.5 V to AVDD, and never leave REF floating - a floating REF forces the modulator into saturation and corrupts all conversions. Designers should also avoid routing the load-cell excitation voltage through the same ground as digital return currents, which is the most common source of gain error in weigh-scale designs.
Informations de conformité
RoHS compliance indicated by '+' suffix in Maxim part number per manufacturer ordering information. REACH and conflict-minerals compliance declared via Maxim-Integrated environmental policy. Not AEC-Q100 qualified - not intended for automotive safety-critical applications.
