MAX1276CTC+ - 12-Bit 1.8Msps SAR ADC | Analog Devices
MPN： MAX1276CTC+ ✓ 啟用中MAX1276CTC+ 概覽
A SAR ADC is a type of analog-to-digital converter that uses a binary search (successive approximation) through a precision DAC and comparator to digitize each input sample in N clock cycles for N bits of resolution. SAR converters are valued for deterministic latency, low latency between sample and conversion result, no pipeline delay, and excellent DC accuracy with no missing codes - they are widely used in precision industrial, instrumentation, and motor-control data-acquisition front ends where deterministic conversion timing simplifies synchronization with control loops.
Key features include a true-differential analog input that rejects common-mode noise, an internal 2.5V reference (no external reference required for many applications), a low power consumption of around 18 mW at 1.8 Msps, and a high-speed SPI/QSPI/MICROWIRE-compatible serial interface. The 12-pin TQFN (4x4 mm) package is small and supports reflow soldering on standard SMT lines, while the wide analog supply range (2.7V to 3.6V) makes the part easy to integrate into 3.3V industrial and data-acquisition designs.
The architecture uses a charge-redistribution DAC and an internal low-drift reference, achieving 12-bit resolution with no missing codes and an SINAD typically around 71 dB at fIN close to Nyquist. The serial interface is straightforward and supports daisy-chaining multiple MAX1276/MAX1278 devices on a single SPI bus when more than one channel is needed in a system.
Typical applications include process control and industrial data acquisition, motor control current/voltage sensing, weigh scales, portable instrumentation, and front-end digitizers for 4-20 mA loop-powered sensors. The combination of true-differential input and integrated reference simplifies board layout and BOM compared to discrete SAR solutions. For battery-powered designs, the part's low shutdown current extends operating time when the ADC is sampled intermittently.
When designing with this ADC, keep analog and digital grounds short and tied at a single point, place the 0.1 uF bypass capacitor as close as possible to the AVDD pin, and route the serial-clock line with a series resistor or controlled impedance to limit ringing at 1.8 Msps. Using the internal reference removes the need for an external reference but sacrifices full-scale range flexibility; for applications above 2.5V FS, an external reference can be driven into REF.
This page synthesizes distributor pricing, drop-in alternatives from the same ADI pin-compatible family and from cross-brand sources, and practical design notes not found in the manufacturer datasheet, giving engineers a faster path from datasheet to BOM.
直接替換替代品，適用於 MAX1276CTC+ — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： MAX1276CTC+ （相同外形與佔位） — 差異在於 Package, Number of Channels, Resolution, Input Type, Internal Reference.
MAX1276CTC+T
✅ 直接替換聯絡詢價
查看資料表 →MAX1276ETC+
✅ 直接替換📋 參考替代品（不在目錄中）
MAX1278CTC+
✅ 直接替換📋 參考替代品（不在目錄中）
MAX1225CTC+
✅ 直接替換聯絡詢價
查看資料表 →MAX1224CTC+
✅ 直接替換聯絡詢價
查看資料表 →MAX1078CTC+T
✅ 直接替換聯絡詢價
查看資料表 →MAX1276CTC+ 最大額定值與電氣特性
| 解析度 | 12 bits |
| Sample Rate | 1.8 Msps |
| Number of Channels | 1 input |
| Architecture | SAR (Successive Approximation) |
| Input Type | True-differential (single-ended capable) |
| 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 |
| External Reference Option | Yes |
| Data Interface | SPI / QSPI / MICROWIRE-compatible serial |
| Power Consumption | 18 mW at 1.8 Msps (typical) |
| 工作溫度 | 0 C to +70 C (commercial) |
| 封裝 | 12-pin TQFN (4x4 mm) |
| 安裝類型 | Surface Mount |
| RoHS 狀態 | Compliant |
| Lead-Free | Yes |
MAX1276CTC+ 腳位配置
| 腳位 1 | AIN+ — Positive analog input (true-differential) |
| 腳位 2 | AIN- — Negative analog input (true-differential) / common-mode return |
| 腳位 3 | GND — Analog ground |
| 腳位 4 | REF — Reference voltage input/output (internal 2.5V or external drive) |
| 腳位 5 | AVDD — Analog supply voltage, 2.7V to 3.6V |
| 腳位 6 | DVDD — Digital supply voltage, 2.7V to 3.6V |
| 腳位 7 | CS — Chip select (active low, enables serial interface) |
| 腳位 8 | DOUT — Serial data output (SPI MISO) |
| 腳位 9 | SCLK — Serial clock input |
| 腳位 10 | SHDN — Shutdown input (active low, powers down the device) |
| 腳位 11 | DGND — Digital ground |
| 腳位 12 | NC — Not connected (per datasheet) - exposed pad on bottom is thermal/ground pad |
典型應用
MAX1276CTC+ 適用於 7 應用s: Process Control and Industrial Data Acquisition, Motor Control Current and Voltage Sensing, Weigh Scales and Bridge Sensor Digitization, Portable Instrumentation and Handheld Meters, Front-End Digitizer for 4-20 mA Loop Sensors, Communication and RF Power Rail Digitization, Data Acquisition Cards and Modular Instruments.
Process Control and Industrial Data Acquisition
The MAX1276CTC+ suits process-control DAQ front ends because of its 1.8 Msps throughput, true-differential input that rejects ground-loop noise on long sensor runs, and integrated 2.5V reference that removes a BOM item. Its 12-bit, no-missing-codes resolution is enough to digitize 4-20 mA loop voltages, thermocouple/thermistor bridges, and pressure/strain-gauge outputs in PLC modules and industrial instrumentation racks.
推薦
Motor Control Current and Voltage Sensing
In FOC and trapezoidal motor-drive boards, the MAX1276CTC+ digitizes shunt-resistor current and DC-bus voltage at 1.8 Msps, supporting control loops up to several kHz with margin. Its true-differential input tolerates the large common-mode dv/dt swings of a switching inverter, and the integrated reference simplifies bring-up. Designers often pair it with a digital isolator to feed back to the host MCU/FPGA controller running the algorithm.
推薦
Weigh Scales and Bridge Sensor Digitization
Weigh-scale front ends digitize load-cell bridges where true-differential input is essential for rejecting thermocouple and mains-borne common-mode noise. The MAX1276CTC+ drives the bridge with its excitation from the analog supply and digitizes the bridge output through its true-differential input. The integrated 2.5V reference simplifies calibration, and the SPI/QSPI serial interface minimizes pin count on the host MCU, ideal for compact bench and industrial scales.
推薦
Portable Instrumentation and Handheld Meters
Handheld multimeters and portable instrumentation rely on a low-power ADC that can also do fast transient capture. The MAX1276CTC+ delivers 1.8 Msps for transient recording at ~18 mW and shuts down between conversions for battery life. The 12-pin TQFN package is small enough to fit slim handheld enclosures, and the SPI interface ties cleanly to common low-power Cortex-M microcontrollers used in these designs.
推薦
Front-End Digitizer for 4-20 mA Loop Sensors
Field-sensor conditioning boards convert a 4-20 mA loop into a voltage and digitize it; the MAX1276CTC+ provides 1.8 Msps of throughput and 12-bit accuracy with a true-differential input that rejects ground-potential differences between the field sensor and the controller. The integrated reference and small TQFN package reduce board area in DIN-rail-mounted modules, where space and BOM cost matter.
推薦
Communication and RF Power Rail Digitization
RF-transceiver and digital-radio boards need clean rail monitoring with deterministic latency to align fast readings with packet-level events. The MAX1276CTC+'s SAR architecture has no pipeline delay, so a sample triggered by an FPGA MARK strobe is available in N+1 clocks, ideal for capturing rail transients during TX/RX burst events. The part's small TQFN footprint and SPI interface keep the BOM minimal in crowded RF designs.
推薦
Data Acquisition Cards and Modular Instruments
Modular data-acquisition cards (PCIe/USB/LXI) often use 1.8 Msps, 12-bit SAR ADCs as their per-channel digitizer. The MAX1276CTC+ integrates the reference and provides true-differential inputs, simplifying the analog front end. The serial interface allows multiple MAX1276/MAX1278 chips to be daisy-chained on a single SPI bus, scaling channel count without consuming extra FPGA pins.
推薦
推薦產品摘要
工程參考資料，適用於 MAX1276CTC+ — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | MAX1276CTC+T | MAX1276ETC+ | MAX1278CTC+ | MAX1225CTC+ | MAX1224CTC+ | MAX1078CTC+T |
|---|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 12-TQFN (4x4) | 12-TQFN (4x4) - same | 12-TQFN (4x4) - same | 12-TQFN (4x4) - same | 12-TQFN (4x4) - same | 12-TQFN (4x4) - same | 12-TQFN (4x4) - same |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits | 10 bits |
| Sample Rate | 1.8 Msps | 1.8 Msps | 1.8 Msps | 225 ksps | 225 ksps | 125 ksps | 1.8 Msps |
| Number of Channels | 1 input | 1 input | 1 input | 1 input | 1 input | 1 input | 2 inputs |
| 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 | 2.7 V to 3.6 V | 2.7 V to 3.6 V |
| Internal Reference | 2.5 V | 2.5 V | 2.5 V | 2.5 V | 2.048 V | 2.048 V | 2.048 V |
| Temperature Grade | 0 C to +70 C (commercial) | 0 C to +70 C | -40 C to +85 C (industrial) | 0 C to +70 C | 0 C to +70 C | 0 C to +70 C | -40 C to +85 C (industrial) |
| Approx. Unit Price (1 pc) | USD 7.20 | USD 7.20 | USD 8.40 | USD 5.10 | USD 6.50 | USD 5.85 | USD 6.00 |
主要差異化特點
- Highest sample rate in 12-pin TQFN (4x4) 12-bit SAR family (對比MAX1278CTC+)
- Industrial temperature grade option in identical package (對比MAX1276ETC+)
- 2.5V internal reference tailored to 3.3V systems (對比MAX1225CTC+)
設計說明
Place the 0.1 uF AVDD and DVDD bypass capacitors as close to the IC pins as possible, with short traces to a solid ground pour. Keep the analog and digital grounds separated by a star under the IC and join them at a single point near the device. Route SCLK with a series 33 ohm resistor near the source to slow the edge and reduce overshoot, which can cause erroneous conversion results at 1.8 Msps with long SPI traces.
True-differential AIN+/AIN- traces should be routed as a matched pair with the same length and consistent spacing to a keepout ground. Avoid routing them near the SCLK, DOUT, or CS traces which can couple noise into the analog front end. For best common-mode rejection above 1 kHz, place a common-mode RC network or ferrite across the inputs near the IC.
Do not exceed the absolute maximum ratings of AVDD/DVDD, including transients during hot-plug events. The REF pin should not be loaded below the recommended bypass value (>= 0.1 uF) for stable internal-reference operation. When using SHDN to reduce power, allow the part to reach full power-down state before restarting conversion to avoid spurious first readings.
合規資訊
RoHS compliance and lead-free per ADI product page. REACH, halogen-free, and conflict-minerals status not stated in the verified web data - marked unknown.
