MAX1276CTC+T - 12-Bit 1.8Msps Differential ADC | Maxim Integrated
MPN: MAX1276CTC+T ✓ פעילMAX1276CTC+T סקירה
What is a SAR ADC? A successive-approximation-register (SAR) analog-to-digital converter is a class of Nyquist-rate ADC that converts an analog input to a digital code by stepping through bit decisions from MSB to LSB using a binary search through an internal capacitive DAC. SAR ADCs sit in the hierarchy: ADC -> data converter -> mixed-signal IC -> semiconductor. They are favored over delta-sigma ADCs for multi-channel multiplexed systems and over pipelined ADCs when true-differential input ranges, low latency, and deterministic behavior are needed.
Key features of the MAX1276CTC+T include a true-differential input stage supporting 0 to VREF (unipolar) or ±VREF (bipolar) signal swings, an internal 2.5V low-drift reference, an external reference option for ratio-metric conversions, and a high-speed SPI/QSPI/MICROWIRE-compatible serial interface. The 12-bit resolution with no missing codes and ±1 LSB INL delivers clean, monotonic conversion results. The integrated track-and-hold accepts input bandwidths well above Nyquist, preserving signal integrity for AC-coupled measurement front-ends.
The device uses a charge-redistribution SAR architecture with an automatic power-down mode between conversions, dropping supply current to under 1 µA when idle. This makes it well-suited for battery-powered or duty-cycled instrumentation where the part only wakes during a sample window. The serial output delivers 12-bit results MSB-first with a maximum 20 MHz SCLK rate, allowing direct connection to microcontrollers, DSPs, and FPGAs without glue logic.
Typical applications include data-acquisition systems, pen-digitizers and touch-screen controllers, portable instrumentation, battery-powered medical devices, and process-control I/O modules. The +3V single-supply operation simplifies power-tree design in mixed 3.3V/1.8V systems where a clean analog rail is essential. The internal reference eliminates the external reference IC on most boards, reducing BOM cost and PCB area.
When designing with the MAX1276CTC+T, place a 0.1 µF ceramic bypass capacitor within 5 mm of the AVDD pin and a 10 µF bulk tantalum or ceramic cap on the supply rail. Keep the analog input traces short and guard them with a ground pour to minimize coupled noise; the true-differential input stage rejects common-mode disturbance, but PCB asymmetry degrades CMRR. The exposed pad (EP) must be soldered to a clean analog ground plane for thermal and electrical performance.
This page synthesizes distributor pricing for the tape-and-reel MAX1276CTC+T variant, pin-compatible same-family drop-in alternatives (MAX1276ETC+T, MAX1276CTC+), and practical layout notes not collected in the manufacturer datasheet alone.
חלופות תחליף ישיר עבור MAX1276CTC+T — אותו מארז, תואם פין-לפין. חלקים במארז שונה הדורשים עיבוד מחדש של ה-PCB אינם נכללים.
וריאנטים בסדרה זו
דגמים מאותה סדרה התואמים Drop-in עם MAX1276CTC+T (אותו גורם צורה וטביעת רגל) — שונים ב Number of Channels, Package, Input Type, Resolution, Analog Supply Voltage.
MAX1276CTC+
✅ Drop-Inצור קשר לקבלת מחיר
הצג גיליון נתונים ←MAX1276ETC+T
✅ Drop-In📋 חלופה להתייחסות (לא בקטלוג)
MAX1276ETC+
✅ Drop-In📋 חלופה להתייחסות (לא בקטלוג)
MAX1076CTC+T
✅ Drop-In ⚠️ מפרטים לא מאומתיםצור קשר לקבלת מחיר
הצג גיליון נתונים ←MAX1078CTC+T
✅ Drop-In ⚠️ מפרטים לא מאומתיםצור קשר לקבלת מחיר
הצג גיליון נתונים ←MAX1225CTC+T
✅ Drop-Inצור קשר לקבלת מחיר
הצג גיליון נתונים ←MAX1276CTC+T דירוגים מרביים ומאפיינים חשמליים
| רזולוציה | 12 bit |
| Sample Rate | 1.8 Msps |
| Number of Channels | 1 |
| Architecture | SAR (Successive Approximation) |
| Input Type | True Differential |
| Analog Supply Voltage | +2.7 V to +3.6 V |
| Digital Supply Voltage | +2.7 V to +3.6 V |
| Internal Reference | 2.5 V (on-chip bandgap) |
| External Reference Option | Yes |
| Input Range (Unipolar) | 0 to VREF |
| Input Range (Bipolar) | ±VREF |
| INL (Max) | ±1 LSB |
| DNL | No missing codes |
| Supply Current at 1.5 Msps | 4.5 mW / 3 V |
| Power-Down Current | < 1 µA |
| ממשק | SPI / QSPI / MICROWIRE-compatible serial |
| Maximum SCLK | 20 MHz |
| מארז | 12-TQFN (4x4 mm) with exposed pad |
| טמפרטורת פעולה | -40 °C to +85 °C |
| Temperature Grade | Commercial |
| סוג הרכבה | Surface Mount |
| סטטוס RoHS | Compliant |
תצורת פינים של MAX1276CTC+T
| פין 1 | AVDD — Analog supply voltage (+2.7 V to +3.6 V); bypass with 0.1 µF + 10 µF caps |
| פין 2 | AGND — Analog ground; tie to clean analog ground plane |
| פין 3 | AIN+ — Positive true-differential analog input |
| פין 4 | AIN- — Negative true-differential analog input |
| פין 5 | REF — Reference I/O; internal 2.5 V or external reference input |
| פין 6 | REFMODE — Reference mode select / REF (per datasheet) |
| פין 7 | DVDD — Digital supply voltage (+2.7 V to +3.6 V) |
| פין 8 | DGND — Digital ground |
| פין 9 | CS — Active-low chip-select for serial interface |
| פין 10 | SCLK — Serial clock input, up to 20 MHz |
| פין 11 | DOUT — Serial data output, MSB-first |
| פין 12 | EP — Exposed pad; must be soldered to analog ground |
יישומים טיפוסיים
MAX1276CTC+T מתאים עבור 6 יישוםs: Data Acquisition Systems, Pen-Digitizer and Touch-Screen Controllers, Portable Instrumentation, Process-Control I/O Modules, Battery-Powered Medical Devices, Sensor Signal Conditioning Hubs.
Data Acquisition Systems
The MAX1276CTC+T's 1.8 Msps sample rate and true-differential input stage make it a strong fit for multi-channel data-acquisition front-ends where AC and DC signals must be captured without missing codes. In a typical 8-channel mux'd DAS, the ADC delivers 12-bit monotonic output at full speed with ±1 LSB INL, supporting measurement of strain gauges, thermocouples (with PGA front-end), and 4-20 mA loop shunts. Power dissipation of 4.5 mW at 1.5 Msps plus sub-1 µA power-down keeps the part cool in dense backplanes. The internal 2.5 V reference eliminates one external IC on the BOM.
מומלץ
Pen-Digitizer and Touch-Screen Controllers
The MAX1276CTC+T is purpose-built for resistive touch-screen and pen-digitizer controllers, where its true-differential input directly digitizes the X-plate and Y-plate voltages across the touch panel. The 1.8 Msps throughput resolves stylus hover and fast pen strokes without lag, and the single +3.3 V supply matches the system rail of most touch-screen SoCs. Internal 2.5 V reference with external override allows ratiometric measurements that cancel rDS(on) drift in the touchscreen switches. Sub-microamp shutdown is essential for always-on tablet designs that sleep between touches.
מומלץ
Portable Instrumentation
Handheld DMMs, oscilloscope front-ends, and field-test gear benefit from the MAX1276CTC+T's combination of 1.8 Msps throughput, 4.5 mW dissipation, and <1 µA power-down current. Engineers building battery-powered instruments can duty-cycle the ADC: wake, sample, sleep - which extends battery life by orders of magnitude versus a continuously running ADC. The 12-pin TQFN (4x4 mm) footprint saves board space in compact probe designs, and the 2.7-3.6 V supply aligns directly with single-cell Li-ion chemistries after regulation.
מומלץ
Process-Control I/O Modules
Industrial process-control analog input modules digitize 4-20 mA loops, RTD bridges, and 0-10 V field signals with high noise immunity. The MAX1276CTC+T's true-differential input rejects common-mode noise injected by long cable runs from PLC field terminals, while ±1 LSB INL supports the 0.1% accuracy class required by most loop controllers. The SPI-compatible serial interface connects directly to industrial ARM Cortex-M MCUs without glue logic, and the -40 °C to +85 °C commercial operating range covers most factory-floor enclosures. Internal reference simplifies CE/UL certification by reducing the analog BOM count.
מומלץ
Battery-Powered Medical Devices
Portable medical monitors - pulse oximeters, glucose meters, single-lead ECG patches - rely on the MAX1276CTC+T's low-power operation and small TQFN-12 package to fit inside disposable or wearable form factors. The ADC's <1 µA power-down current enables coin-cell-powered designs that sample intermittently and sleep between measurements. True-differential inputs reject common-mode interference from 50/60 Hz mains coupling, important when the patient cable acts as an antenna. Single +3 V operation matches a CR2032 or single Li-ion cell after boost regulation.
מומלץ
Sensor Signal Conditioning Hubs
Industrial IoT sensor hubs aggregate multiple analog sensor outputs (temperature, pressure, flow, gas) into a single MCU. The MAX1276CTC+T can be paired with an external analog mux to sequentially digitize 4-8 sensor channels at 1.8 Msps aggregate throughput, while its internal 2.5 V reference provides a stable excitation baseline for ratiometric sensors. The serial SPI/QSPI/MICROWIRE interface drops directly into any modern MCU's peripheral set, and the small TQFN-12 package keeps the analog section compact on space-constrained IoT PCBs. Total ADC power at full speed is under 5 mW.
מומלץ
סיכום מוצרים מומלצים
נתוני עזר הנדסיים עבור MAX1276CTC+T — השוואה, הנחיות תכנון ומידע על תאימות.
מדריך בחירה
השוואה עם חלופות
| פרמטר | מוצר זה | MAX1276CTC+ | MAX1276ETC+T | MAX1076CTC+T |
|---|---|---|---|---|
| Brand | Analog Devices (Maxim Integrated) | Analog Devices (Maxim Integrated) | Analog Devices (Maxim Integrated) | Analog Devices (Maxim Integrated) |
| Package | 12-TQFN (4x4) | 12-TQFN (4x4) - same | 12-WQFN (4x4) - drop-in compatible | 12-TQFN (4x4) - same |
| Resolution | 12 bit | 12 bit | 12 bit | 10 bit |
| Architecture | SAR | SAR | SAR | SAR |
| Serial Interface | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI / QSPI / MICROWIRE | SPI (per family) |
מבדילים עיקריים
- Tape-and-reel packaging optimized for high-volume SMT (לעומתMAX1276CTC+)
- True-differential analog input with internal 2.5 V reference (לעומתMAX1076CTC+T (10-bit variant))
- 1.8 Msps throughput at low power (4.5 mW) (לעומתMAX1225CTC+T (dual-channel SAR))
הערות תכנון
Place a 0.1 µF ceramic bypass capacitor within 5 mm of the AVDD pin (pin 1) and a 10 µF bulk tantalum or ceramic capacitor on the supply rail. Keep the analog input traces short and symmetrically routed to preserve the true-differential CMRR; asymmetry of even a few millimeters on the AIN+/AIN- pair can degrade common-mode rejection at high frequencies. The exposed pad (pin 12 / EP) must be soldered to a continuous analog ground pour for thermal dissipation and electrical reference.
Use the internal 2.5 V reference for cost-sensitive designs; route the REF pin directly to the analog input network without series resistance. For ratio-metric bridge measurements (load cells, RTDs), drive REF with the bridge excitation voltage and connect AIN+/AIN- across the bridge to cancel excitation drift. Decouple REF with a 0.1 µF + 10 µF cap pair at the pin to suppress reference noise from coupling into conversions.
The MAX1276CTC+T accepts input bandwidths well above Nyquist, but place a low-pass RC filter (typically 1 kΩ + 1 nF) ahead of AIN+/AIN- to limit wideband noise and prevent aliasing of out-of-band interference. Keep CS high between conversions to enter the automatic power-down mode; CS low wakes the part for the next sample. Tie any unused DOUT state to a known logic level through the MCU's pull-up to avoid spurious wake events.
Do not leave the exposed pad (EP) floating - it must be soldered to analog ground for proper electrical and thermal performance. Do not exceed the absolute maximum AVDD/DVDD rating of +3.6 V (transients above this will damage the part). When using an external reference, ensure REFMODE is configured correctly per the datasheet or the ADC may default to internal reference. Finally, never drive AIN+/AIN- before power is applied - use a series resistor or PGA-controlled ramp if hot-plug events are possible.
מידע על תאימות
RoHS and REACH compliant per Maxim/Analog Devices product page. Not AEC-Q100 qualified - this is a commercial-grade part for industrial and consumer use. For automotive applications, consider AEC-Q100 qualified members of the broader Maxim ADC portfolio.
