MAX131CMH - 3.5-Digit ADC with Bandgap Reference | Maxim
料号： MAX131CMH ✓ 量产中MAX131CMH 概述
A 3.5-digit ADC is a special-purpose data converter optimized for measurement displays rather than high-resolution waveform acquisition. It can represent a decimal reading with approximately three and a half significant digits, which is useful for measuring slowly changing quantities such as temperature, pressure, voltage, current, or process variables. The integrated bandgap reference supplies a stable reference for the conversion system, reducing the need for an external precision reference in suitable measurement designs.
Key product characteristics include the 3.5-digit conversion format, integrated bandgap reference, 44-terminal MQFP construction, and commercial temperature grade as shown in the verified distributor data. The MAX131 family is also available in MAX131A versions, which the manufacturer states have a maximum temperature coefficient of 50 ppm/°C, compared with 100 ppm/°C for the standard MAX130 and MAX131 families. These variants provide a useful selection distinction when reference stability is more important than basic display-oriented measurement resolution.
The MAX131 is generally used where a controller, display, or system input needs a stable, low-cost measurement value. The common-mode input arrangement allows the converter to be used with suitable external signal-conditioning networks for sensors and resistive dividers. The reference architecture is important because measurement accuracy depends not only on the ADC itself but also on the reference voltage, input conditioning, grounding, and the time required for conversion.
Designers should pay particular attention to input range, differential input polarity, conversion timing, reference decoupling, and the layout of sensitive analog signals. The 44-pin MQFP package requires adequate PCB area and careful routing, especially when the measured signal is close to the converter's resolution limit. The manufacturer product page and datasheet should be consulted for the complete electrical characteristics, timing diagrams, reference limits, and recommended application circuit.
This page combines the verified manufacturer description, distributor package information, source links, application guidance, and design notes for engineers evaluating the MAX131CMH. Pricing and availability should be checked against current distributor records because component inventory and lead time can change after the verified data date.
直接替换替代料： MAX131CMH ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
MAX131CMH+D
✅ 直接替换📋 参考替代料（不在目录中）
MAX131CMH+
✅ 直接替换📋 参考替代料（不在目录中）
MAX131CMH+TD
✅ 直接替换📋 参考替代料（不在目录中）
MAX131AMH
✅ 直接替换 ⚠️ 规格未核验📋 参考替代料（不在目录中）
MAX130CMH
✅ 直接替换 ⚠️ 规格未核验联系询价
MAX131CMH 最大额定值与电气特性
| ADC Resolution | 3.5 digits |
| Converter Type | 3 1/2-digit ADC with bandgap reference |
| Reference | Integrated bandgap reference |
| 封装 | 44-MQFP (10x10) |
| Terminal Count | 44 terminals |
| Package Shape | Square |
| Terminal Form | Gull wing |
| Temperature Grade | Commercial |
| Maximum Temperature Coefficient | 100 ppm/°C for standard MAX130 and MAX131 families |
| Input Architecture | Differential analog input |
| Conversion Architecture | Dual-slope |
| Manufacturer List Price | $8.76 starting price |
| Verified Distributor Price | $2.3792 starting price from LCSC |
MAX131CMH square 引脚配置指南
MAX131CMH（square 封装）的引脚配置。 该模拟元件具有输入、输出和电源引脚。请参阅制造商数据手册以了解失调调零、补偿和使能引脚配置。适用于信号调理和放大器电路。
暂无详细引脚数据： MAX131CMH.
请参阅 数据手册 以查看完整引脚配置。
典型应用
MAX131CMH 适用于 6 应用s: Digital Panel Meter, Temperature Measurement, Industrial Process Monitoring, Laboratory Voltage Measurement, Power Supply Readout, Portable Measurement Instrument.
Digital Panel Meter
The MAX131CMH is well suited to digital panel meters because it combines a 3.5-digit dual-slope ADC with an integrated bandgap reference in a 44-MQFP package. It can convert a conditioned sensor or divider signal into a stable decimal measurement for display and control. The integrated reference removes the need for a separate precision reference within the converter, while the commercial temperature grade targets general commercial equipment. Engineers should use the manufacturer's recommended input network, reference bypass capacitors, and acquisition timing. The standard MAX131 family is specified with a maximum temperature coefficient of 100 ppm/°C; MAX131A variants reduce this to 50 ppm/°C when tighter reference stability is needed.
推荐
Temperature Measurement
For temperature measurement, the MAX131CMH can digitize a conditioned resistive or voltage-based sensor signal intended for a numeric display. Its 3.5-digit resolution is appropriate for slowly varying temperatures and avoids the complexity of a general-purpose waveform ADC. The integrated bandgap reference establishes the conversion reference, while external circuitry must supply linearization, excitation, filtering, and differential input conditioning. Reference stability directly affects measurement repeatability, so the standard 100 ppm/°C MAX131 specification should be checked against the required temperature error. For greater stability, the manufacturer states that MAX131A parts improve the maximum temperature coefficient to 50 ppm/°C.
推荐
Industrial Process Monitoring
MAX131CMH can be used in industrial process-monitoring equipment that presents a measured pressure, level, or flow value rather than performing high-rate waveform acquisition. The dual-slope 3.5-digit conversion format is suited to relatively slow process signals, and the integrated bandgap reference supports repeatable readings without a separate reference IC. A practical implementation uses an instrumentation amplifier or differential filter, protection networks, and an input range appropriate to the transducer. Commercial temperature grade should be verified against the actual enclosure temperature. If the process requires faster updates or greater resolution, a general-purpose ADC may be preferable despite the MAX131's simpler measurement-focused architecture.
推荐
Laboratory Voltage Measurement
The MAX131CMH can serve as the measurement engine in a bench instrument or laboratory display module requiring a stable three-and-a-half-digit reading. Its integrated bandgap reference simplifies the reference architecture, while the differential input allows the measurement front end to reject common-mode noise when the source is properly balanced. The implementation should define the full-scale input range before scaling, include input protection, and follow the manufacturer grounding and reference-decoupling layout. Measurement accuracy will also be limited by resistor tolerances, leakage, converter timing, and temperature drift. For precision laboratory results, verify the full datasheet limits and consider the MAX131A family's improved 50 ppm/°C reference coefficient.
推荐
Power Supply Readout
A MAX131CMH implementation can monitor a scaled supply voltage and display the result on an operator panel. This is useful in power modules, battery systems, and laboratory supplies where a readable voltage measurement is more valuable than high-speed sampling. The ADC's integrated bandgap reference reduces the number of precision components, and the differential input can be connected to a balanced divider and filter. Designers should include adequate transient protection, account for converter acquisition time, and avoid routing sensitive input traces beside digital or switching nodes. Supply regulation and display update requirements are application-specific, so the measured range and refresh rate should be checked against the manufacturer's timing characteristics.
推荐
Portable Measurement Instrument
The MAX131CMH is applicable to portable or handheld measurement products where a three-and-a-half-digit numerical result, stable reference, and compact integrated solution are desired. The dual-slope conversion architecture is appropriate for slowly changing sensor values, and the 44-MQFP package provides the required analog and digital connections in a surface-mount design. Portable-product designs should verify supply-voltage limits, power consumption, battery impact, and warm-up behavior from the official datasheet because those values were not included in the supplied search snippets. Printed-circuit layout should keep input and reference paths short and shielded from display, keypad, and power-converter signals to preserve measurement stability.
推荐
推荐产品汇总
工程参考数据： MAX131CMH ——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 | MAX131CMH+D | MAX131CMH+ | MAX131CMH+TD | MAX131AMH | MAX130CMH |
|---|---|---|---|---|---|---|
| Package | 44-MQFP (10x10) | 44-MQFP (10x10) | 44-MQFP (10x10) | 44-MQFP (10x10) | 44-MQFP (10x10) | 44-MQFP (10x10) |
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Converter Type | 3 1/2-digit ADC with bandgap reference | 3 1/2-digit ADC with bandgap reference | 3 1/2-digit ADC with bandgap reference | 3 1/2-digit ADC with bandgap reference | 3 1/2-digit ADC with bandgap reference | 3 1/2-digit ADC with bandgap reference |
| Reference | Integrated bandgap reference | Integrated bandgap reference | Integrated bandgap reference | Integrated bandgap reference | Integrated bandgap reference | Integrated bandgap reference |
| Maximum Temperature Coefficient | 100 ppm/°C | 100 ppm/°C | 100 ppm/°C | 100 ppm/°C | 50 ppm/°C | 100 ppm/°C |
| Terminal Count | 44 terminals | 44 terminals | 44 terminals | 44 terminals | 44 terminals | 44 terminals |
关键差异点
- Integrated bandgap reference （对比 MAX130CMH)
- Improved reference temperature coefficient （对比 MAX131CMH+D)
- Measurement-focused conversion format （对比 MAX131CMH+TD)
设计说明
Keep the MAX131CMH differential input traces short, symmetrical, and away from switching nodes, display drivers, and high-current return paths. Route the pair away from ground-plane breaks and use a continuous reference plane beneath the analog section. The supplied verified data confirms a 44-MQFP package but does not provide the manufacturer's exact layout drawing, so the current datasheet layout guidance should take priority over general recommendations.
Follow the manufacturer's recommended reference bypass and input-capacitor network exactly. Reference decoupling is especially important because the MAX131 family's stated 100 ppm/°C coefficient establishes the baseline stability of the integrated bandgap reference, while MAX131A improves it to 50 ppm/°C. Supply voltage, current, capacitor values, and permitted ESR were not included in the verified snippets, so do not infer them from generic dual-slope ADC designs.
Do not treat the 3.5-digit resolution as equivalent to a general-purpose 14-bit ADC for dynamic signal measurement. Dual-slope conversion requires sufficient integration time, and the usable reading can be affected by input noise, common-mode voltage, differential imbalance, and reference drift. Confirm the input range and timing from the official datasheet, and avoid driving the inputs beyond their absolute-maximum ratings.
合规信息
The supplied verified snippets do not state RoHS, REACH, lead-free, halogen-free, or conflict-minerals status. The device is not an automotive-qualified variant in the supplied data.
