MAX1276CTC+T - 12-Bit 1.8Msps Differential ADC | Maxim Integrated
料号： MAX1276CTC+T ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $5.62 | $5.62 |
| 10 | $5.05 | $50.50 |
| 100 | $4.49 | $449.00 |
| 500 | $3.96 | $1,980.00 |
| 1,000 | $3.42 | $3,420.00 |
MAX1276CTC+T 概述
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.
直接替换替代料： MAX1276CTC+T ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
本系列中的变体
可与以下型号直接替换的同系列型号： MAX1276CTC+T （相同外形与封装尺寸） ——差异在于 Number of Channels, Package, Input Type, Resolution, Analog Supply Voltage.
快速对比工具——选择替代料号进行并排对比：
MAX1276CTC+
✅ 直接替换✓ 有现货
$4.32 / 个
查看数据手册 →MAX1276ETC+T
✅ 直接替换📋 参考替代料（不在目录中）
MAX1276ETC+
✅ 直接替换📋 参考替代料（不在目录中）
MAX1076CTC+T
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$3.42 / 个
查看数据手册 →MAX1078CTC+T
✅ 直接替换 ⚠️ 规格未核验✓ 有现货
$5.1 / 个
查看数据手册 →MAX1225CTC+T
✅ 直接替换✓ 有现货
$4.65 / 个
查看数据手册 →MAX1276CTC+T 最大额定值与电气特性
| 分辨率 | 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 |
| 接口 | SPI / QSPI / MICROWIRE-compatible serial |
| Maximum SCLK | 20 MHz |
| 封装 | 12-TQFN (4x4 mm) with exposed pad |
| 工作温度 | -40 °C to +85 °C |
| Temperature Grade | Commercial |
| 安装类型 | Surface Mount |
| RoHS 状态 | Compliant |
MAX1276CTC+T 引脚配置
| 引脚 1 | AVDD — Analog supply voltage (+2.7 V to +3.6 V); bypass with 0.1 µF + 10 µF caps |
| 引脚 2 | AGND — Analog ground; tie to clean analog ground plane |
| 引脚 3 | AIN+ — Positive true-differential analog input |
| 引脚 4 | AIN- — Negative true-differential analog input |
| 引脚 5 | REF — Reference I/O; internal 2.5 V or external reference input |
| 引脚 6 | REFMODE — Reference mode select / REF (per datasheet) |
| 引脚 7 | DVDD — Digital supply voltage (+2.7 V to +3.6 V) |
| 引脚 8 | DGND — Digital ground |
| 引脚 9 | CS — Active-low chip-select for serial interface |
| 引脚 10 | SCLK — Serial clock input, up to 20 MHz |
| 引脚 11 | DOUT — Serial data output, MSB-first |
| 引脚 12 | EP — Exposed pad; must be soldered to analog ground |
典型应用
MAX1276CTC+T 适用于 6 应用s: 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.
推荐
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.
推荐
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.
推荐
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.
推荐
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.
推荐
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.
推荐
推荐产品汇总
工程参考数据： MAX1276CTC+T ——对比、设计指导和合规信息。
选型指南
与替代料对比
| 参数 | 本产品 | 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) |
关键差异点
- Tape-and-reel packaging optimized for high-volume SMT （对比 MAX1276CTC+)
- True-differential analog input with internal 2.5 V reference （对比 MAX1076CTC+T (10-bit variant))
- 1.8 Msps throughput at low power (4.5 mW) （对比 MAX1225CTC+T (dual-channel SAR))
设计说明
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.
合规信息
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.
