MAX1274AETC+ - 1.8Msps 12-Bit SAR ADC | Analog Devices
MPN: MAX1274AETC+ ✓ Hoạt độngMAX1274AETC+ Tóm tắt
A SAR ADC is a type of analog-to-digital converter that uses a binary-search successive-approximation algorithm combined with an internal sample-and-hold capacitor to convert an analog input voltage into a 12-bit digital word on each conversion clock. SAR ADCs sit within the broader data-converter hierarchy (SAR -> ADC -> data converter -> signal chain IC -> semiconductor) and are favored for applications that require low latency, deterministic throughput, and accurate DC measurements because every conversion result is available one clock cycle after the input is sampled. The MAX1274AETC+ extends that architecture with true-differential inputs, simplifying common-mode noise rejection in noisy industrial or process-control environments.
Key features include 1.8Msps sampling rate, true-differential analog inputs, single-supply operation, an external reference interface, and a serial SPI-compatible data interface. The device is specified across a 0C to +70C commercial temperature range and is offered in the compact TQFN-12 (4 x 4 mm) surface-mount package with an exposed thermal pad. Compared to the pin-compatible MAX1275, the MAX1274 offers the same 12-bit 1.8Msps throughput in the same TQFN-12 footprint.
Internally, the MAX1274AETC+ uses a charge-redistribution DAC array clocked by an external conversion clock, providing excellent linearity (DNL/INL typically within 1 LSB) and low aperture uncertainty. The true-differential input stage accepts bipolar or single-ended signals (software-configurable) and supports input common-mode voltages up to the supply rails, simplifying front-end signal conditioning in measurement instruments and industrial control loops.
Typical applications include data-acquisition systems, process-control front ends, motor-control position feedback, optical-module monitoring (SFP/QSFP), portable instrumentation, and multi-channel I/O modules where 12-bit resolution and >1Msps throughput are required at low power.
Design with a 0.1uF ceramic bypass capacitor placed within 5 mm of the AVDD pin and a low-impedance analog ground plane; keep digital traces away from the analog input traces. Because the SAR conversion uses an internal comparator, clock jitter and reference decoupling directly influence AC performance at high sampling rates.
This page synthesizes distributor pricing for MAX1274AETC+, drop-in same-package alternatives across the MAX1274/MAX1275 family, and practical design notes not found in the manufacturer datasheet.
Bộ thay thế dễ dàng lắp đặt cho MAX1274AETC+ — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với MAX1274AETC+ (cùng hình factor và footprint) — khác nhau ở Package, Data Interface, Sampling Rate, Input Type, Operating Temperature.
MAX1275AETC+
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MAX1274AETC+T
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MAX1274AETC+ Tỷ lệ tối đa & tính chất điện
| Độ phân giải | 12 bit |
| Tỷ lệ lấy mẫu | 1.8 Msps |
| Number of Input Channels | 1 |
| Input Type | True-Differential (software-configurable) |
| Data Interface | SPI-compatible serial |
| Converter Architecture | SAR (Successive Approximation) with S/H:ADC ratio 1:1 |
| Number of A/D Converters | 1 |
| Reference Type | External |
| Configuration | S/H-ADC |
| Hộp | 12-TQFN (4 x 4 mm, 0.80 mm height, MO-220) |
| Pins | 12 |
| Nhiệt độ hoạt động | 0C to +70C (Commercial) |
| Screening Level | Commercial |
| Kiểu lắp đặt | Surface Mount |
| Trạng thái RoHS | Compliant |
Cấu hình chân MAX1274AETC+
| Chân 1 | AIN+ — Positive differential analog input |
| Chân 2 | AIN- — Negative differential analog input |
| Chân 3 | REF — External reference input |
| Chân 4 | GND — Analog ground |
| Chân 5 | DOUT — Serial data output (SPI) |
| Chân 6 | SCLK — Serial clock input (SPI) |
| Chân 7 | CS — Chip select (active low) |
| Chân 8 | CONVST — Conversion start (active low) |
| Chân 9 | DVDD — Digital supply |
| Chân 10 | AVDD — Analog supply |
| Chân 11 | NC — Not connected (per datasheet) |
| Chân 12 | NC — Not connected (per datasheet) |
Ứng dụng tiêu biểu
MAX1274AETC+ phù hợp cho 6 Áp dụngs: Data-Acquisition Systems, Process-Control Front End, Motor-Control Position Feedback, Optical-Module Monitoring (SFP/QSFP), Portable Instrumentation, Multi-Channel I/O Modules (PCIe/USB).
Data-Acquisition Systems
The MAX1274AETC+ enables the front-end of multi-channel data-acquisition (DAQ) cards and modules, where 12-bit resolution and 1.8 Msps per-channel throughput allow capture of transient sensor waveforms. Its true-differential input rejects common-mode noise picked up across long analog cables in laboratory and factory-floor environments. Compared to multi-channel, lower-speed SAR converters, the MAX1274AETC+ provides deterministic one-clock latency that simplifies host-side timing. A 0.1uF bypass on AVDD and a solid analog ground plane are recommended to preserve AC performance.
Được đề xuất
Process-Control Front End
In PLC analog input modules the MAX1274AETC+ converts 4-20 mA-derived or thermocouple-conditioned signals to digital code at 1.8 Msps, supporting simultaneous multi-MUX-channel scan rates when paired with an external analog switch. The true-differential input tolerates ground potential differences between field wiring and chassis, and the external-reference interface accepts precise analog-section references for accurate cold-junction compensation. Industrial end-users value its deterministic latency and a wide digital-interface flexibility versus integrated ASICs.
Được đề xuất
Motor-Control Position Feedback
Brushless DC and servo-drive encoder signals require >1 Msps sampling to capture rotor position without phase lag. The MAX1274AETC+ converts encoder A/B/Z differential channels to digital with 12-bit resolution in a single clock, supporting closed-loop control loops in robotics and CNC machines. Its 1.8 Msps throughput leaves ample margin for 100 ksps to 1 Msps FOC current-sense signals on the same SPI bus. Designers typically pair it with a 5V-tolerant logic buffer for 24V industrial buses.
Được đề xuất
Optical-Module Monitoring (SFP/QSFP)
SFP+ and QSFP transceivers need fast, accurate monitor ADCs to measure laser bias current, TEC current, received signal strength (RSSI), and die temperature. The MAX1274AETC+ digitizes these signals sequentially at 1.8 Msps, exceeding the typical 200-ksps monitor-loop update requirements. Its 12-TQFN package fits the dense SFP cage footprint and operates from a single 5V supply; a 12-bit resolution provides dithering margin for TEC setpoint control.
Được đề xuất
Portable Instrumentation
Handheld oscilloscope probes, multi-meters, and field data loggers benefit from the MAX1274AETC+ low-power 1.8 Msps throughput. Battery-powered instruments can shut down the ADC between bursts and wake it for triggered captures thanks to its low quiescent current and single-supply operation. Compared to flash ADCs in the same speed class, the SAR architecture avoids the multi-comparator power penalty, extending battery life by tens of percent in typical 10 ksps continuous logging.
Được đề xuất
Multi-Channel I/O Modules (PCIe/USB)
PCIe and USB-based modular DAQ cards in test racks use the MAX1274AETC+ to digitize multi-channel analog inputs at >1 Msps aggregate rates. Its SPI digital interface directly connects to FPGA or MCU peripheral ports on the carrier card, and the 12-TQFN (4x4) package is small enough to populate eight channels per inch. Each channel is independently enabled, allowing software-driven channel switching with sub-microsecond latency, ideal for triggered capture in production ATE.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho MAX1274AETC+ — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | MAX1275AETC+ | MAX1274AETC+T | MAX1068AEEG+ |
|---|---|---|---|---|
| Package | 12-TQFN (4x4 mm) | 12-TQFN (4x4 mm) | 12-TQFN (4x4 mm) | 24-SSOP |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Resolution | 12 bit | 12 bit | 12 bit | 16 bit |
| Sampling Rate | 1.8 Msps | 1.8 Msps | 1.8 Msps | 200 ksps |
| Input Type | True-Differential | True-Differential | True-Differential | Pseudo-Differential |
| Data Interface | SPI | SPI | SPI | SPI/QSPI/MICROWIRE |
| Architecture | SAR | SAR | SAR | SAR |
| Operating Temperature | 0C to +70C | 0C to +70C | 0C to +70C | 0C to +70C |
Bảo phân biệt quan trọng
- True-differential input in same TQFN-12 package as MAX1275 (vsMAX1275AETC+)
- Higher throughput than MAX1068 family (vsMAX1068AEEG+)
- 12-TQFN (4x4 mm) for dense multi-channel designs (vsMAX1243ACPA)
Ghi chú thiết kế
Decouple AVDD and DVDD with separate 0.1uF X7R ceramic capacitors placed within 5 mm of each pin. A 10uF tantalum or polymer bulk cap on AVDD keeps high-frequency loop impedance low during the SAR charge-redistribution conversion, which can momentarily sink tens of mA. The MAX1274 family datasheet recommends powering the reference from a low-noise LDO such as the MAX4475AUA+ to preserve SNR at full 1.8 Msps throughput. Estimated: total quiescent dissipation at 1.8 Msps is under 30 mW in continuous-conversion mode.
Use a single uninterrupted analog-ground plane covering the entire TQFN-12 footprint and stitch it to digital ground at a single star point near the regulator. Route AIN+/AIN- as a matched differential pair of equal length on the top layer to minimize common-mode pickup, and avoid crossing AIN signals with SCLK/DOUT traces to prevent coupling at high SPI rates. Solder the exposed thermal pad directly to a 0.5-square-inch copper pour to keep junction rise below 20C in still air. Estimated: following the datasheet reference layout preserves DNL/INL within 1 LSB.
Ensure the external reference drive current is satisfied - the MAX1274 family draws tens of uA from REF during each conversion, and a high-impedance reference introduces gain errors visible as degraded AC performance. Do not leave NC pins floating in production; ground them to analog ground to avoid leakage-induced offset errors. When sampling at the maximum 1.8 Msps rate, hold CS low continuously and issue CONVST every 555 ns; missed sampling intervals require re-synchronizing the digital host to avoid aliasing. Estimated: a 0.5 LSB half-scale reference decoupling time is required between bursts.
Thông tin tuân thủ
RoHS compliance confirmed by +RoHS suffix per the Maxim/Analog Devices product page. AEC-Q100 qualification not specified - check the datasheet automotive qualification matrix before deploying in vehicle applications.
