MAX174BCWI+ - 12-Bit 125 kSPS Complete ADC | Maxim Integrated
料号： MAX174BCWI+ ✓ 量产中| 数量 | 单价 | 小计 |
|---|---|---|
| 1 | $28.5 | $28.50 |
| 10 | $26.1 | $261.00 |
| 100 | $23.4 | $2,340.00 |
| 500 | $20.85 | $10,425.00 |
| 1,000 | $18.65 | $18,650.00 |
MAX174BCWI+ 概述
Key specifications include 12-bit resolution with no missing codes, a 0 V to +10 V or 0 V to +20 V input range (jumper or strap selectable), a 10 V on-chip buried-zener reference (TrimDAC-compatible, ±0.3% accuracy grade B), a parallel microprocessor interface, and a low supply requirement of +5 V plus optionally ±12 V to ±15 V for analog inputs. Conversion time is 8 µs at full throughput, with three interface modes for tying to 8-bit, 12-bit, or 16-bit data buses.
An SAR ADC (Successive Approximation Register Analog-to-Digital Converter) is a widely used ADC architecture that uses a binary search algorithm to resolve the input voltage one bit per clock cycle, achieving an excellent trade-off between speed, resolution, and power consumption. SAR ADCs sit at the second tier of the data-converter hierarchy: faster than integrating ADCs, slower than flash or pipeline ADCs, but offering very high DC accuracy and low latency. They occupy a key role in the broader power management and signal-conditioning IC family, alongside DACs, references, and multiplexers.
The MAX174BCWI+ uses Maxim's BiCMOS construction, which reduces power dissipation relative to older bipolar-only designs. The internal reference and clock reduce external component count to a bare minimum: a handful of bypass capacitors and decoupling at the supply pins are sufficient for most applications. The device can also be operated in ROM mode for reduced-microcontroller designs.
Typical applications include process-control data acquisition boards, instrumentation front-ends, motor-control feedback loops, medical monitoring equipment, and any high-accuracy industrial measurement requiring an easy-to-interface 12-bit ADC with built-in reference. The wide analog input range (up to ±10 V bipolar) makes the part especially attractive in legacy industrial systems that use ±10 V or 4 mA to 20 mA signaling. Pairing the MAX174BCWI+ with a precision op-amp front-end (such as the MAX4250) and an instrumentation amp (such as the MAX4194) builds a complete 12-bit analog input module.
When designing with the MAX174BCWI+, observe the Analog Devices datasheet supply-decoupling recommendation: place 10 µF tantalum and 0.1 µF ceramic bypass capacitors as close to the supply pins as possible. Re-calibrate the internal reference at first startup using the TrimDAC inputs if ±1 LSB absolute accuracy is required, especially at the limits of the operating temperature range.
This page synthesizes distributor pricing, drop-in same-brand alternatives, and practical design notes that complement the manufacturer datasheet - ideal for engineers evaluating the MAX174BCWI+ for new designs or as a drop-in for an end-of-life replacement in an existing board.
直接替换替代料： MAX174BCWI+ ——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： MAX174BCWI+ （相同外形与封装尺寸） ——差异在于 Resolution, Package, Architecture, Mounting Type, Terminal Form.
快速对比工具——选择替代料号进行并排对比：
MAX174ACWI+
✅ 直接替换📋 参考替代料（不在目录中）
MAX174BCWI
✅ 直接替换📋 参考替代料（不在目录中）
MAX174BCWI+T
✅ 直接替换📋 参考替代料（不在目录中）
MAX173CWG
✅ 直接替换✓ 有现货
$8.95 / 个
查看数据手册 →MAX162BCNG+
✅ 直接替换✓ 有现货
$7.5 / 个
查看数据手册 →MAX174BCWI+ 最大额定值与电气特性
| 分辨率 | 12 bits |
| 采样率 | 125 kSPS |
| Conversion Time | 8 µs |
| Number of Channels | 1 |
| Architecture | SAR (Successive Approximation) |
| 输入电压范围 | 0 V to +10 V or 0 V to +20 V (unipolar); ±5 V or ±10 V (bipolar) |
| Internal Reference | 10 V buried zener, ±0.3 % (grade B) |
| 接口 | Parallel (8/12/16-bit bus compatible) |
| Supply Voltage (Digital) | +5 V |
| Supply Voltage (Analog) | ±12 V to ±15 V (bipolar operation) |
| Integral Nonlinearity | ±1 LSB max (grade B) |
| Differential Nonlinearity | ±1 LSB max (no missing codes) |
| 工作温度 | 0 °C to +70 °C |
| 封装 | 28-pin SOIC (wide, 7.5 mm body width) |
| 安装类型 | Surface Mount |
MAX174BCWI+ 引脚配置
| 引脚 1 | DB11 — Data bit 11 (MSB) - parallel output |
| 引脚 2 | DB10 — Data bit 10 - parallel output |
| 引脚 3 | DB9 — Data bit 9 - parallel output |
| 引脚 4 | DB8 — Data bit 8 - parallel output |
| 引脚 5 | DB7 — Data bit 7 - parallel output |
| 引脚 6 | DB6 — Data bit 6 - parallel output |
| 引脚 7 | DB5 — Data bit 5 - parallel output |
| 引脚 8 | DB4 — Data bit 4 - parallel output |
| 引脚 9 | DB3 — Data bit 3 - parallel output |
| 引脚 10 | DB2 — Data bit 2 - parallel output |
| 引脚 11 | DB1 — Data bit 1 - parallel output |
| 引脚 12 | DB0 — Data bit 0 (LSB) - parallel output |
| 引脚 13 | STATUS — End-of-conversion status flag |
| 引脚 14 | /CS — Chip select, active low |
| 引脚 15 | /RD — Read strobe, active low |
| 引脚 16 | DGND — Digital ground |
| 引脚 17 | DVDD — +5 V digital supply |
| 引脚 18 | REF — +10 V reference output / input (TrimDAC) |
| 引脚 19 | REFIN — Reference input (TrimDAC adjustment node) |
| 引脚 20 | AGND — Analog ground |
| 引脚 21 | +VCC — +15 V analog supply (positive rail for bipolar inputs) |
| 引脚 22 | -VCC — -15 V analog supply (negative rail for bipolar inputs) |
| 引脚 23 | AIN — Analog input (unipolar 0-10 V / 0-20 V or bipolar ±5 V / ±10 V) |
| 引脚 24 | RANGE — Input range select (input current 0.2 mA) |
| 引脚 25 | BIP — Bipolar mode select (offset adjustment) |
| 引脚 26 | CAL — Calibration mode select |
| 引脚 27 | BPOFF — Bipolar offset adjustment pin |
| 引脚 28 | TRIM — Reference trim (TrimDAC) |
典型应用
MAX174BCWI+ 适用于 6 应用s: Process Control Data Acquisition, Industrial Instrumentation Front-End, Motor Control Feedback, Medical Monitoring Equipment, Test and Measurement Equipment, Legacy Industrial Bus Digitizers.
Process Control Data Acquisition
The MAX174BCWI+ suits multi-channel process-control front-ends where 12-bit resolution at 125 kSPS is sufficient and a wide bipolar input range is mandatory. Its 0 V to +10 V and ±10 V input ranges cover 4-20 mA current-loop receivers (with a 100 Ω shunt) and ±10 V industrial transducers without external signal conditioning. The on-chip 10 V buried-zener reference removes the need for an external precision reference, cutting BOM cost by ~$2 per ADC channel. Place 10 µF tantalum plus 0.1 µF ceramic bypass capacitors at each supply pin to keep conversion noise below 1 LSB. Compared with newer SAR ADCs the MAX174BCWI+ offers a familiar digital interface that drops straight into 8051-style legacy controllers.
推荐
Industrial Instrumentation Front-End
Industrial instrumentation subsystems benefit from the MAX174BCWI+'s true-bipolar ±10 V input range, which lets a single ADC digitize both unipolar 0-10 V sensor outputs and bipolar ±10 V signals from strain gauges and load cells without external level shifting. The parallel 8/12/16-bit interface is a clean fit for legacy microcontrollers and bus arbiters, and the on-board 10 V reference with ±0.3 % accuracy helps the overall system meet ±1 LSB at full scale without external trimming. In typical rack-mount instrumentation this ADC sits behind a low-noise op-amp buffer and feeds a 12-bit parallel bus to a host processor; the conversion-time penalty (~8 µs) is acceptable for 10 kHz update rate applications like temperature control loops.
推荐
Motor Control Feedback
Brushless-DC and industrial servo drives use the MAX174BCWI+ in position/velocity feedback loops where 12-bit resolution and 125 kSPS throughput give sub-millisecond loop update rates. The chip's +5 V digital supply matches typical microcontrollers, while the ±15 V analog supply lets the ADC directly digitize current-sense signals from shunt resistors amplified to a ±10 V range. The STATUS pin provides an end-of-conversion flag for synchronizing control-loop computation with sampling, ensuring deterministic timing. Track-and-hold behavior on the input makes the ADC tolerant of high-dV/dt PWM edges typical in 3-phase inverter modules.
推荐
Medical Monitoring Equipment
Patient monitoring devices use the MAX174BCWI+ to digitize analog signals from ECG, pulse-oximeter, and temperature sensors where 12-bit resolution and the ±10 V input range suffice for moderate-amplitude physiological signals. The internal buried-zener reference and well-defined INL/DNL figures aid IEC 60601-1 compliance testing because gain drift stays within ±1 LSB across the commercial operating range. The parallel interface simplifies integration with medically certified microcontrollers and CPLDs, reducing firmware complexity. Layout should keep digital switching currents away from the analog input traces to maintain CMRR above 80 dB.
推荐
Test and Measurement Equipment
Bench-top DMMs, dataloggers, and laboratory instruments often use the MAX174BCWI+ as the main DC measurement ADC thanks to its no-missing-codes 12-bit performance and on-board 10 V reference. Engineers repurposing the part for multimeter-grade inputs pair it with a precision input divider and front-end protection clamp, achieving 0.025 % DC accuracy on the 10 V range. Multiple chips can be paralleled with chip-select multiplexing to build a low-cost multi-channel data acquisition module where each channel is software-accessible via a parallel bus. The commercial temperature range (0 °C to +70 °C) suits lab and light-industrial environments.
推荐
Legacy Industrial Bus Digitizers
Many legacy 4 mA-to-20 mA current-loop and ±10 V analog-bus industrial networks persist in factory automation, where designers retrofit the MAX174BCWI+ to digitize a 4-20 mA signal with a 100 Ω shunt and feed it to a modern microcontroller or bus transceiver. The wide ±10 V input range handles +/- 10 V signaling without external protection, and the 8 µs conversion time provides ample throughput for 100 Hz digital-loop update rates typical in process control. The 28-pin SOIC wide-body package is hand-solderable for low-volume retrofit manufacturing, helping maintenance engineers build replacement boards without specialized fine-pitch equipment.
推荐
推荐产品汇总
工程参考数据： MAX174BCWI+ ——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 | MAX174ACWI+ | MAX174BCWI | MAX174BCWI+T | MAX173CWG | MAX162BCNG+ |
|---|---|---|---|---|---|---|
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Package | 28-SOIC (wide) | 28-SOIC (wide) - same | 28-SOIC (wide) - same | 28-SOIC (wide) - same | 28-SOIC (wide) - same | 28-SOIC - same |
| Resolution | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits | 12 bits |
| Operating Temperature | 0 °C to +70 °C | 0 °C to +70 °C | 0 °C to +70 °C | 0 °C to +70 °C | 0 °C to +70 °C | 0 °C to +70 °C |
关键差异点
- Trade-off - internal reference reduces BOM but is only ±0.3 % accurate （对比 MAX174ACWI+)
- RoHS finish is a lead-free finish verified at distributors （对比 MAX174BCWI (no "+"))
- Tube packaging suited for low-volume kitting （对比 MAX174BCWI+T)
- Higher throughput (125 kSPS) vs MAX162 family （对比 MAX162BCNG+)
设计说明
Estimated: at +5 V digital supply drawing I_DD and ±15 V analog rails drawing I_CC, total power dissipation is approximately 150 mW to 250 mW. Add 10 µF tantalum and 0.1 µF ceramic bypass capacitors as close as possible to the DVDD (+5 V), +VCC (+15 V), and -VCC (-15 V) supply pins. A ferrite bead between the +5 V analog and digital rails is recommended to prevent digital switching noise from corrupting the conversion result. Estimated based on datasheet typical figures.
Use a single ground plane subdivided between analog (AGND) and digital (DGND) sections, with the connections made only at the AGND/DGND pins of the ADC. Route the parallel data bus away from the analog input traces to avoid digital coupling into the sample-and-hold input; the data bus should be 50 Ω characteristic impedance if you are running longer than 50 mm. Power-trace widths should be sized for at least 200 mA current to handle inrush during power-up without dropping more than ~50 mV.
Three pitfalls to avoid: (1) Operating the AIN pin outside the absolute-maximum range can latch-up the device - add external clamping diodes if the input can exceed +VCC+0.3 V or fall below -VCC-0.3 V during fault conditions. (2) The on-chip reference requires a 50 µA to 500 µA load to maintain regulation - never short REF to AGND. (3) Forgetting to strap the RANGE and BIP pins correctly before applying analog input can produce incorrect conversion results and corrupt calibration; always verify these pins with a multimeter at power-up.
The MAX174BCWI+ tracks analog input continuously even when not converting, so high-impedance signal sources should be buffered by an op-amp (e.g. MAX4250) to avoid droop. Source impedance below 1 kΩ is recommended to keep settling errors below ¼ LSB; higher impedances degrade INL at full-scale inputs. For 8-channel multiplexing, use a Maxim DG408 or equivalent low-charge-injection multiplexer and provide at least 1 µs between channel switch and conversion start to allow the S&H capacitor to settle.
合规信息
"+" suffix indicates RoHS compliance. AEC-Q100 not applicable (commercial-grade only).
