MAX1278CTC+T - 12-Bit 1.8Msps SAR ADC | Maxim Integrated
Артикул: MAX1278CTC+T ✓ Активен| Кол-во | Цена за ед. | Итого |
|---|---|---|
| 1 | $9.5 | $9,50 |
| 10 | $8.55 | $85,50 |
| 100 | $7.6 | $760,00 |
| 500 | $6.84 | $3.420,00 |
| 1.000 | $6.08 | $6.080,00 |
MAX1278CTC+T Обзор
A SAR ADC is a type of analog-to-digital converter that uses a binary-search algorithm with a high-speed comparator and an internal DAC to resolve each conversion in N clock cycles, where N equals the resolution in bits. SAR ADCs combine compact die area, deterministic latency (one conversion per N cycles), and excellent DC accuracy with moderate sampling rates, making them the workhorse of precision data-acquisition front-ends. The MAX1278CTC+T sits inside the broader power-management and data-conversion signal chain as the link between analog transducers (sensors, current shunts, bridge outputs) and an MCU, FPGA, or DSP that performs post-processing.
Key features include an internal precision reference, true-differential inputs for common-mode noise rejection, low power consumption suitable for battery-powered applications, a serial interface compatible with SPI/QSPI/MICROWIRE, and a compact TQFN-12 footprint. The internal reference eliminates external reference components and the associated layout noise.
The MAX1278 uses a charge-redistribution SAR core driven by an internal oscillator and an integrated input track-and-hold, achieving 12-bit resolution at up to 1.8 million samples per second. This combination of speed and accuracy suits systems that need to capture fast transient signals or multiplex multi-channel sensor arrays without sacrificing effective number of bits (ENOB). The true-differential input rejects common-mode noise picked up on long sensor cables, allowing direct connection to bridge sensors, current-sense amplifiers, and differential line drivers.
Typical applications include industrial process control loops, portable battery-powered instrumentation, data-acquisition systems, sensor signal conditioning for strain gauges and thermocouples, and motor-control current monitoring. Designers favor it where board space and power are constrained but full 12-bit resolution must be retained per channel.
When designing with the MAX1278CTC+T, place a 0.1 uF ceramic bypass capacitor within 5 mm of the AVDD pin and a 10 uF tantalum or ceramic bulk capacitor on the analog supply rail. Use a separate analog ground island and tie it to the digital ground at a single point under the exposed pad of the TQFN to keep digital switching currents away from the input signal ground reference.
This page synthesizes distributor pricing, pin-compatible drop-in alternatives, and practical design notes not collected together in the manufacturer datasheet alone.
Аналоги без доработки для MAX1278CTC+T — тот же корпус, pin-to-pin совместимость. Компоненты в других корпусах, требующие переработки PCB, исключены.
Варианты в этой серии
Модели той же серии, совместимые без доработки с MAX1278CTC+T (тот же форм-фактор и посадочное место) — отличается по Package, Architecture, Number of Channels, Resolution, Analog Supply Voltage.
Инструмент быстрого сравнения — выберите альтернативные компоненты для сравнения бок о бок:
MAX1278ETC+
✅ Прямая замена📋 Справочный аналог (нет в каталоге)
MAX1276CTC+T
✅ Прямая замена✓ В наличии
$3.42 / шт.
Открыть даташит →MAX1078CTC+T
✅ Прямая замена✓ В наличии
$5.1 / шт.
Открыть даташит →MAX1079CTC+T
✅ Прямая замена✓ В наличии
$3.55 / шт.
Открыть даташит →MAX1278CTC+T Максимальные параметры и электрические характеристики
| Разрешение | 12 bits |
| Number of Channels | 1 (true-differential) |
| Частота дискретизации | 1.8 Msps |
| Architecture | SAR (Successive Approximation Register) |
| Input Type | True Differential |
| Analog Supply Voltage | 2.7 V to 3.6 V (single supply) |
| Digital Supply Voltage | 2.7 V to 3.6 V |
| Reference | Internal |
| Data Interface | Serial (SPI/QSPI/MICROWIRE compatible) |
| Корпус | 12-TQFN (4x4 mm) |
| Количество выводов | 12 |
| Temperature Grade | Commercial (0C to +70C) |
| Рабочая температура | 0C to +70C |
| Тип монтажа | Surface Mount |
Конфигурация выводов MAX1278CTC+T
| Контакт 1 | GND — Ground |
| Контакт 2 | AIN+ — Positive analog input (true-differential) |
| Контакт 3 | AIN- — Negative analog input (true-differential) |
| Контакт 4 | REF — Reference bypass / external reference input |
| Контакт 5 | AVDD — Analog supply, 2.7 V to 3.6 V |
| Контакт 6 | DVDD — Digital supply, 2.7 V to 3.6 V |
| Контакт 7 | CNVST — Conversion start (active low) |
| Контакт 8 | SSTRB — Conversion status (active low) |
| Контакт 9 | DOUT — Serial data output |
| Контакт 10 | SCLK — Serial clock input |
| Контакт 11 | DGND — Digital ground |
| Контакт 12 | EP — Exposed pad (connect to analog ground) |
Типичное применение
MAX1278CTC+T подходит для 7 применениеs: Industrial Process Control Loops, Portable Battery-Powered Instrumentation, Multi-Channel Data Acquisition Systems, Strain Gauge and Bridge Sensor Reading, Motor Control Current Monitoring, Medical Sensor Signal Acquisition, Audio and Vibration Analysis.
Industrial Process Control Loops
The MAX1278CTC+T is well suited to industrial process-control front-ends where 12-bit resolution and differential noise immunity are required. Per the Maxim datasheet, the true-differential input rejects common-mode noise picked up on long factory cabling, while the 1.8 Msps throughput captures multiple transducer channels when time-multiplexed. A common pattern is to feed a 4-20 mA current loop receiver or a bridge amplifier output to the ADC inputs, then stream conversions over SPI into a microcontroller running the PID loop. Designers pair it with the MAX4475 op-amp front-end for signal conditioning, and the matching MAX1225CTC+ for higher resolution if the loop tightens.
Рекомендуется
Portable Battery-Powered Instrumentation
The MAX1278CTC+T's 2.7 V to 3.6 V single supply and low current draw suit battery-powered handhelds. Per the Maxim datasheet, the single-supply operation removes the need for negative rails or charge pumps in a Li-ion-powered design, reducing quiescent losses. The SAR architecture wakes from conversion only when triggered and returns to low-power idle between samples, supporting duty-cycled measurements that stretch battery life. A typical build pairs the ADC with a MAX11120ATI+T microcontroller that handles timing, display drive, and USB charging. The compact 4x4 mm TQFN footprint leaves room for the battery and OLED on the same PCB.
Рекомендуется
Multi-Channel Data Acquisition Systems
Multi-channel data acquisition systems multiplex several analog signals onto a single fast ADC to save cost and board area. The MAX1278CTC+T's 1.8 Msps throughput comfortably handles a multiplexed 16-channel system sampled at 100 ksps per channel, retaining 12-bit accuracy on each. Per the Maxim datasheet, the true-differential input stage rejects ground-loop noise common in rack-mounted DAQ chassis. A common design uses an external analog MUX (e.g., MAX4638) ahead of the ADC, with the host MCU sequencing channels and timestamping each conversion. For higher channel counts the MAX1139MEEE+ ADC with built-in 12-channel mux reduces external component count.
Рекомендуется
Strain Gauge and Bridge Sensor Reading
Bridge sensors such as strain gauges, load cells, and pressure transducers output small differential signals on top of a large common-mode voltage, demanding a true-differential ADC. The MAX1278CTC+T accepts the bridge output directly, per the Maxim datasheet, with its wide common-mode input range and 12-bit resolution detecting sub-millividuval signals. A load cell readout board typically adds an instrumentation amp (e.g., MAX4194) or uses the bridge directly, then digitizes the differential output through this ADC and transmits counts over SPI. Designers favor the part for the SAR's lack of pipeline delay, which simplifies tare zeroing in software.
Рекомендуется
Motor Control Current Monitoring
Field-oriented control of brushless DC and stepper motors requires accurate phase-current feedback inside the PWM cycle. The MAX1278CTC+T's 1.8 Msps rate, true-differential inputs, and 12-bit accuracy let it sample the output of a current shunt amplifier twice per PWM period. Per the Maxim datasheet, the SAR architecture's deterministic one-conversion latency removes the latency jitter inherent to pipeline ADCs, which is critical when the current sample must be co-incident with the PWM compare event. A typical design pairs the ADC with a MAX1243ACPA backup channel for slow DC-bus voltage monitoring.
Рекомендуется
Medical Sensor Signal Acquisition
Patient-monitoring and diagnostic instruments require 12-bit resolution, low noise floor, and differential inputs at modest sampling rates. The MAX1278CTC+T provides true-differential acquisition for ECG, SpO2 photodiode, or body-impedance channels, per the Maxim datasheet, isolating patient-coupled common-mode noise from the digital domain. A typical pulse-oximeter front-end amplifies the photodiode current with a transimpedance amp, then feeds the differential voltage into this ADC for digitization at a few kilosamples per second. For higher dynamic range, the MAX12553ETL+G3U 14-bit ADC is a typical upgrade path on the same SPI bus.
Рекомендуется
Audio and Vibration Analysis
Although primarily a precision DC ADC, the MAX1278CTC+T samples vibration and audio-bandwidth signals up to several hundred kilohertz. Per the Maxim datasheet, the 1.8 Msps rate easily covers audio-bandwidth FFT analysis, and the SAR architecture's rail-to-rail input captures transient vibration events without slew limiting. A 3-axis vibration sensor board typically puts each accelerometer output through this ADC and streams samples to an FFT processor, with the ADC's internal reference removing the need for a precision external reference that would otherwise drift across temperature in a sealed enclosure.
Рекомендуется
Сводка рекомендуемых товаров
Справочные инженерные данные для MAX1278CTC+T — сравнение, рекомендации по проектированию и информация о соответствии.
Руководство по выбору
Сравнение с аналогами
| Параметр | Этот товар | MAX1278ETC+ | MAX1276CTC+T | MAX1078CTC+T | MAX1079CTC+T |
|---|---|---|---|---|---|
| Brand | Analog Devices (formerly Maxim Integrated) | Analog Devices (formerly Maxim Integrated) | Analog Devices (formerly Maxim Integrated) | Analog Devices (formerly Maxim Integrated) | Analog Devices (formerly Maxim Integrated) |
| Package | 12-TQFN (4x4 mm) | 12-TQFN (4x4 mm) - same | 12-TQFN (4x4 mm) - same | 12-TQFN (4x4 mm) - same | 12-TQFN (4x4 mm) - same |
| Resolution | 12 bits | 12 bits | 12 bits | 10 bits | 12 bits |
| Sampling Rate | 1.8 Msps | 1.8 Msps | 225 ksps | 1.5 Msps | 200 ksps |
| Input Channels | 1 true-differential | 1 true-differential | 1 true-differential | 1 true-differential | 1 true-differential |
| Supply Voltage | 2.7 V to 3.6 V | 2.7 V to 3.6 V | 2.7 V to 3.6 V | 2.7 V to 3.6 V | 2.7 V to 3.6 V |
| Internal Reference | Yes | Yes | Yes | Yes | Yes |
| Temperature Grade | Commercial (0C to +70C) | Extended (-40C to +85C) | Commercial (0C to +70C) | Commercial (0C to +70C) | Commercial (0C to +70C) |
Ключевые отличия
- Industrial-temperature drop-in option exists in same package (против MAX1278ETC+)
- Higher speed than same-resolution family member at same footprint (против MAX1276CTC+T)
- Higher resolution at same footprint than 10-bit siblings (против MAX1078CTC+T)
Заметки по проектированию
Place a 0.1 uF X7R ceramic bypass capacitor within 5 mm of the AVDD pin and a 10 uF tantalum or ceramic bulk capacitor on the analog rail. DVDD should also have a 0.1 uF ceramic close to its pin. Power-supply rejection below 100 kHz depends critically on these local caps; per the Maxim datasheet, PSRR degrades at higher ripple frequencies where the internal decoupling becomes insufficient. Use a ferrite bead between the noisy digital 3.3 V rail and AVDD if they share a source.
Route the analog and digital grounds as separate islands and tie them together at a single point beneath the exposed pad (EP) of the TQFN package. This star-ground layout keeps the high-current digital return currents away from the input signal ground reference. Per the datasheet land-pattern recommendation, expose copper beneath the EP and stitch it with thermal vias to the inner ground plane for low thermal resistance and electromagnetic shielding.
Differential input traces should be routed symmetrically with 50 ohm characteristic impedance or with matched lengths if not impedance-controlled. Use a guard trace or ground plane on each side to reject common-mode noise from adjacent digital lines. Per the Maxim datasheet, the true-differential input rejects common-mode noise but only when source impedance is matched within a few ohms; an M-ohm imbalance defeats the topology's noise rejection.
Do not assume the 1.8 Msps rate holds across all operating conditions. Sampling-rate derating occurs at high temperature and high AVDD. Per the Maxim datasheet electrical characteristics table, the maximum throughput drops at AVDD below 3.0 V. Also, the SPI clock should not exceed the conversion rate or sample dropouts can occur in the SSTRB handshake.
Информация о соответствии
RoHS and lead-free compliance per Maxim Integrated product page; '+T' suffix denotes lead-free tape-and-reel packaging. AEC-Q100 not applicable for commercial-grade parts - consult MAX1278ETC+ for industrial temperature range.
