MAX1284ACSA+T - 12-Bit 400ksps Serial ADC | Maxim Integrated
料号： MAX1284ACSA+T ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $9.85 | $9.85 |
| 10 | $9.12 | $91.20 |
| 100 | $8.04 | $804.00 |
| 500 | $7.21 | $3,605.00 |
| 1,000 | $6.45 | $6,450.00 |
MAX1284ACSA+T 概述
An ADC (analog-to-digital converter) is a mixed-signal data-acquisition building block that converts a continuous-time, continuous-amplitude analog input into a discrete-time, discrete-amplitude digital code. Successive-approximation (SAR) ADCs use an internal binary-search algorithm and a comparator to resolve each bit in N clock cycles, giving a strong balance of speed, resolution, and power consumption for multi-channel data acquisition, sensor readout, and process-control loops. SAR ADCs sit between sigma-delta (high resolution, low speed) and flash (very high speed, low resolution) architectures in the converter taxonomy.
The MAX1284/MAX1285 family delivers 400 ksps (MAX1284) or 300 ksps (MAX1285) throughput with a 4.5 V to 5.5 V supply and draws only a few mW during conversion. The MAX1284ACSA+T variant (suffix 'A' = automotive-style 'A' grade, 'C' = commercial temperature range 0 C to +70 C, 'SA' = 8-pin SO, '+T' = tape-and-reel packaging). It is a drop-in, higher-speed upgrade for the MAX1240/MAX1241 family in legacy 8-pin SO layouts.
Typical applications include portable data loggers, remote sensor front ends, 4-20 mA loop-powered transmitters, pen digitizers, and patient-monitoring instruments where the combination of small footprint, low power, and serial output is valuable. The 8-pin SO footprint is convenient for hand-probe rework and for retrofitting older 8-pin ADC sockets.
When designing with the MAX1284ACSA+T, place a 0.1 uF ceramic bypass capacitor within 5 mm of the AVDD pin and a 10 uF bulk capacitor at the supply rail. Use a low-impedance analog input with an RC anti-alias filter; SAR input current transients settle best when source impedance is kept below about 1 kohm.
直接替换替代料： MAX1284ACSA+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： MAX1284ACSA+T （相同外形与封装尺寸） ——差异在于 Package, Internal Reference, Architecture, Input Type, Number of Channels.
快速对比工具——选择替代料号进行并排对比：
MAX1285ACSA+T
✅ 直接替换📋 参考替代料（不在目录中）
MAX1284ACSA+
✅ 直接替换📋 参考替代料（不在目录中）
MAX1240ACSA+TG069
✅ 直接替换✓ 有现货
$5.65 / 个
查看数据手册 →MAX1241ACSA+
✅ 直接替换📋 参考替代料（不在目录中）
MAX1062ACSA+
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
MAX1156ACSA+
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
MAX1284ACSA+T 最大额定值与电气特性
| 分辨率 | 12 bits |
| Sampling Rate (MAX1284) | 400 ksps |
| Sampling Rate (MAX1285) | 300 ksps |
| Number of Channels | 1 single-ended |
| Architecture | Successive Approximation (SAR) |
| Input Type | Single-ended analog input |
| Supply Voltage (AVDD) | 4.5 V to 5.5 V (single supply) |
| Internal Reference | Yes (on-chip reference) |
| Digital Interface | SPI/QSPI/MICROWIRE-compatible serial |
| 封装 | 8-pin SO (SOIC-8), 3.9 mm body width |
| 安装类型 | Surface Mount |
| Temperature Grade | Commercial (0 C to +70 C) |
| Process Technology | BiCMOS |
| Track/Hold Bandwidth | High-bandwidth input T/H (datasheet figure) |
| Packaging | Tape and Reel (+T suffix) |
| RoHS 状态 | Compliant (manufacturer product page) |
MAX1284ACSA+T 引脚配置
| 引脚 1 | AVDD — Analog supply, 4.5 V to 5.5 V |
| 引脚 2 | AIN — Analog input (single-ended) |
| 引脚 3 | GND — Analog ground |
| 引脚 4 | REF — Reference bypass/decoupling |
| 引脚 5 | SCLK — Serial clock input (SPI/QSPI/MICROWIRE) |
| 引脚 6 | DOUT — Serial data output |
| 引脚 7 | CS — Active-low chip select |
| 引脚 8 | DVDD — Digital supply (connect to AVDD or logic rail) |
典型应用
MAX1284ACSA+T 适用于 6 应用s: Portable Data Loggers, Remote Sensor Front Ends, Industrial Process Control Inputs, Patient Monitoring Instruments, Pen Digitizer and Touch Tablets, Test & Measurement Instrumentation.
Portable Data Loggers
The MAX1284ACSA+T fits portable data loggers because of its 12-bit 400 ksps throughput, single 4.5-5.5 V supply, and 8-pin SO footprint that fits slim handheld enclosures. Its on-chip reference removes a second IC from the BOM, lowering cost and quiescent current. The SPI-compatible serial output reduces MCU pin count so a small 8-pin MCU can drive the ADC. For a typical 1 ksps logger, the 400 ksps max throughput gives 400x headroom and lets the ADC spend most of its time in power-down mode, dropping average supply current to microamp levels.
推荐
Remote Sensor Front Ends
The MAX1284ACSA+T is a strong match for 4-20 mA loop-powered and battery-operated remote sensor front ends, where low power and small size matter more than raw speed. Its internal reference avoids the additional quiescent draw of an external reference IC, and the 8-pin SO requires minimal PCB area. With the 400 ksps max throughput, the converter spends most of its cycle in shutdown between conversions, helping 4-20 mA loops meet the 3.5 mA budget. The SPI output also lets the MCU share its bus with other sensors.
推荐
Industrial Process Control Inputs
The MAX1284ACSA+T serves in industrial process-control input modules that need to digitize a single 0-5 V analog signal at medium speed. Its 4.5-5.5 V supply matches the 5 V analog rail common in PLC analog-input cards, and its 12-bit resolution gives 1.22 mV LSB for a 5 V full-scale input - enough for many thermocouple-amplifier and pressure-transducer front ends. The SOIC-8 footprint simplifies hand-probe rework during field maintenance. Designers can pair it with a small signal-conditioning op-amp on the same 5 V rail.
推荐
Patient Monitoring Instruments
The MAX1284ACSA+T supports patient-monitoring instruments such as portable pulse oximeters and bedside diagnostic devices where size, low power, and moderate speed are all priorities. The 12-bit resolution is sufficient for pulse-rate and SpO2 trends (typically 1-2 mV per LSB at the front-end amplifier output), and the 8-pin SOIC-8 fits inside a wearable enclosure. Its internal reference reduces calibration drift and component count, important for FDA-cleared medical designs. Pair it with a low-noise op-amp front end for clean ECG-style signals.
推荐
Pen Digitizer and Touch Tablets
The MAX1284ACSA+T is well suited to pen-digitizer and touch-tablet digitizing circuits where the position sensor output is a 0-5 V analog signal sampled at medium speed. At 400 ksps, the MAX1284 can digitize a 100 Hz stylus movement with 4000x oversampling, well beyond the Nyquist requirement. Its SPI interface lets a single MCU service the ADC plus the touch-screen controller on a shared bus. The small 8-pin SO saves critical board area in the slim pen housing. Designers can calibrate linearity in software from the 12-bit codes.
推荐
Test & Measurement Instrumentation
The MAX1284ACSA+T is used in bench and handheld test equipment, including digital multimeters, signal-analyzer front ends, and lab-grade data-acquisition front panels. With 12 bits and 400 ksps, the converter supports a 5 V full-scale input with 1.22 mV LSB - good for voltage, current, and temperature front ends. The internal reference eliminates an external reference and its drift, and the 8-pin SO simplifies probe-station rework. The SPI output also lets the instrument MCU share the bus with a display controller and a flash memory.
推荐
推荐产品汇总
工程参考数据： MAX1284ACSA+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 | MAX1285ACSA+T | MAX1284ACSA+ | MAX1240ACSA+ | MAX1241ACSA+ |
|---|---|---|---|---|---|
| Package | SOIC-8 (3.9 mm body) | SOIC-8 (3.9 mm body) - same | SOIC-8 (3.9 mm body) - same | SOIC-8 (3.9 mm body) - same | SOIC-8 (3.9 mm body) - same |
| Brand | Maxim Integrated | Maxim Integrated - same | Maxim Integrated - same | Maxim Integrated - same | Maxim Integrated - same |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Sampling Rate | 400 ksps | 300 ksps | 400 ksps | lower (older gen) | lower (older gen) |
| Internal Reference | Yes | Yes | Yes | Yes | Yes |
| Supply Voltage | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 4.5 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V |
| Serial Interface | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE | SPI/QSPI/MICROWIRE |
| Channels | 1 single-ended | 1 single-ended | 1 single-ended | 1 single-ended | 1 single-ended |
| Architecture | SAR (BiCMOS) | SAR (BiCMOS) | SAR (BiCMOS) | SAR | SAR |
关键差异点
- 400 ksps vs 300 ksps throughput in the same SOIC-8 footprint （对比 MAX1285ACSA+T)
- Higher speed than the legacy MAX1240/MAX1241 family （对比 MAX1240ACSA+)
- Single 5 V supply (vs 2.7-5.5 V) for 5 V-rail-only systems （对比 MAX1240ACSA+)
设计说明
Place a 0.1 uF ceramic bypass capacitor within 5 mm of the AVDD pin and a 10 uF bulk capacitor at the supply rail, as called out in the Maxim MAX1284/MAX1285 datasheet. SAR ADCs draw sharp transient currents at the sampling instant; the bypass capacitor keeps the local AVDD noise under 50 mVpp. DVDD may be tied to AVDD for the simplest 5 V-only system, or driven from a separate 3.3 V rail if the MCU is at 3.3 V logic.
Keep the analog input source impedance below ~1 kohm, as recommended in the Maxim datasheet. Higher source impedance interacts with the ADC's switched-capacitor input and introduces gain error and distortion. If a higher-impedance sensor must be used, add a low-output-impedance buffer (e.g., a precision op-amp) right at the AIN pin. Also avoid running the AIN trace parallel to digital SCLK or DOUT for any length to limit digital-to-analog crosstalk.
Use a star-ground topology with the AGND and DGND pins tied at the ADC's GND pin, then run a single trace to the board ground plane. Keep the SOIC-8 ADC's exposed analog ground as close to the device as possible. Place the 0.1 uF and 10 uF capacitors on the AVDD trace within 5 mm of the AVDD pin, and connect their ground ends to the same AGND star. This layout is consistent with the Maxim evaluation-kit reference for the MAX1284/MAX1285 family.
合规信息
RoHS/lead-free per Maxim Integrated / Analog Devices product page. Not AEC-Q100 qualified - choose an 'AEC-Q100' grade automotive ADC for automotive use. Commercial temperature range 0 C to +70 C.
