ICL7137CQH - Low-Power 3.5-Digit ADC | Maxim Integrated
料号： ICL7137CQH ✓ 量产中ICL7137CQH 概述
An ADC is an integrated circuit that converts an analog voltage into a numeric value. The dual-slope technique used by the ICL7137CQH integrates the unknown input over a fixed interval and compares it with a reference ramp. A digital counter then measures the integration time required to reach balance. This method is suited to panel meters, laboratory instruments, digital scales, and other systems where stable readings and direct display-driver integration are more important than very high conversion speed.
The ICL7137CQH combines low-power operation with 3.5-digit measurement resolution and direct LCD drive capability. Its 44-pin package provides separate connections for analog measurement inputs, reference circuitry, timing, digital data, and display outputs. The commercial temperature range supports equipment intended for controlled indoor or industrial environments rather than extended automotive, military, or extreme-temperature operation.
The 44-pin QFP package provides adequate connection density for analog, digital, and display functions while supporting surface-mount assembly. The MS-022AB package designation and J-bend terminal form identify a leaded quad flat package. Designers must preserve the package footprint, pin assignment, analog trace geometry, bypass-capacitor placement, and reference-source arrangement when revising a circuit around this converter.
Typical uses include digital panel meters, precision weighing indicators, temperature-display instruments, laboratory measurement equipment, and process-monitoring panels. Direct LCD drive is particularly useful when the converter's digital outputs can operate a display without an additional display-controller IC. In each case, the design must account for reference accuracy, input integration timing, display update rate, and the electrical limits of the connected LCD.
A critical layout consideration is the analog input and reference network. Keep these connections short, place the associated bypass capacitors close to their supply pins, and route digital and display signals away from sensitive analog nodes. Verify timing and conversion behavior with the intended source impedance because the dual-slope measurement integrates current rather than sampling an instantaneous voltage.
This product page organizes the verified electrical, environmental, mechanical, and commercial attributes of the ICL7137CQH. It also identifies same-brand alternatives in the related cross-reference results and adds application, comparison, and design guidance to help engineers evaluate a replacement without overlooking display-driver or measurement-system differences.
直接替换替代料： ICL7137CQH ——相同封装，引脚兼容。需要 PCB 改动的不同封装料号已排除。
ICL7136CQH+TD
✅ 直接替换📋 参考替代料（不在目录中）
ICL7107CQH+TD
✅ 直接替换📋 参考替代料（不在目录中）
ICL7137CQH 最大额定值与电气特性
| Converter Type | Dual-slope analog-to-digital converter |
| Display Resolution | 3.5 digits |
| Low-Power Operation | Low-power device |
| Display Output | Direct LCD driver |
| Package Type | QFP, 10 mm x 10 mm x 2 mm |
| Package Outline | MS-022AB |
| Package Code | QCCJ |
| Terminal Count | 44 terminals |
| Terminal Form | J-bend |
| Package Shape | Square |
| 输入电压范围 | 2.6 V to 3.2 V |
| 工作温度范围 | 0°C to 70°C (32°F to 158°F) |
| Screening Level | Commercial |
| RoHS 状态 | RoHS compliant |
ICL7137CQH square 引脚配置指南
ICL7137CQH（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： ICL7137CQH.
请参阅 数据手册 以查看完整引脚配置。
典型应用
ICL7137CQH 适用于 6 应用s: Digital Panel Meter, Laboratory Measurement Instrument, Digital Weighing Scale, Temperature Display Instrument, Process Monitoring Panel, Portable Meter.
Digital Panel Meter
The ICL7137CQH fits a digital panel meter because it combines a 3.5-digit dual-slope ADC with direct LCD drive in one 44-pin QFP package. Placing the converter at the center of the measurement path reduces the need for a separate display-controller IC and simplifies the relationship between the sampled voltage and displayed digits. The 0°C to 70°C commercial range suits indoor instruments and controlled industrial panels. Designers should preserve the reference network and analog input layout, verify display segment and common-output assignments, and confirm that the 2.6 V to 3.2 V listed input range matches the intended signal and LCD interface.
推荐
Laboratory Measurement Instrument
A laboratory measurement instrument can use the ICL7137CQH to convert a slowly changing analog input into a stable 3.5-digit display value. Dual-slope conversion is appropriate for instruments that value repeatable readings, integrated measurement time, and direct LCD presentation over rapid sampling. The device's 44-pin QFP interface provides access to measurement, timing, reference, digital, and display functions, but it also requires disciplined layout. Keep the analog input and reference paths compact, place bypass components near the relevant pins, and test the complete front end with the source impedance and temperature range planned for the instrument.
推荐
Digital Weighing Scale
The ICL7137CQH is suitable for a basic digital weighing-scale display when the load-cell signal is conditioned into a voltage compatible with the converter's measurement system. The 3.5-digit result format and direct LCD drive suit compact tabletop indicators where the measured weight is presented locally without a separate display processor. A scale designer must carefully balance reference accuracy, signal polarity, integration timing, and display update behavior. Because the ICL7137CQH operates within a 0°C to 70°C commercial range, enclosure heating or temperature compensation may be necessary where the mechanism or electronics experience wider ambient changes.
推荐
Temperature Display Instrument
In a temperature display instrument, the ICL7137CQH can digitize a conditioned sensor voltage and directly drive an LCD showing the measured value. This arrangement is useful for standalone thermometers, environmental monitors, and process-temperature panels where a compact numerical readout is sufficient. The converter's 3.5-digit resolution should be matched to the required display precision, while the external reference and sensor interface determine actual measurement accuracy. Use the manufacturer application information to select stable timing and reference components, and keep display-drive traces separated from sensitive analog inputs to reduce coupling into the measured signal.
推荐
Process Monitoring Panel
The ICL7137CQH can serve as the front-end and display controller in a process-monitoring panel that presents one measured process variable locally. Its direct LCD drive and integrated conversion function simplify systems where an operator needs a local reading but not a high-speed digital interface. For industrial use, keep the device within its 0°C to 70°C rating and isolate it from temperature, vibration, and electrically noisy sections of the enclosure. The analog input, reference, and conversion timing components determine stability, so prototype the complete measurement chain and verify display accuracy before production release.
推荐
Portable Meter
The ICL7137CQH can form the measurement and display core of a portable meter where a compact local LCD is more useful than a serial digital output. Its low-power designation and integrated display drive support battery-operated instrument concepts, although the final current budget depends on the complete converter and LCD operating mode. The 44-pin QFP package is suitable for compact surface-mount assembly, while the 0°C to 70°C range constrains environmental use. Confirm standby current, conversion behavior, and LCD compatibility directly from the manufacturer datasheet, and select reference and timing components that support stable readings over the intended battery-voltage range.
推荐
推荐产品汇总
工程参考数据： ICL7137CQH ——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 | ICL7136CQH+TD | ICL7107CQH+TD |
|---|---|---|---|
| Package | PLCC-44 (QCCJ) | PLCC-44 | PLCC-44 |
| Brand | Maxim Integrated | Analog Devices | Analog Devices |
| Operating Supply Voltage | 9 V minimum in related comparison listing | 9 V minimum in related comparison listing | 4.75 V to 5.25 V in related comparison listing |
| Terminal Count | 44 terminals | 44 terminals | 44 terminals |
关键差异点
- Direct LCD-drive integration （对比 ICL7107CQH+TD)
- Commercial-grade operating range （对比 ICL7136CQH+TD)
- Exact 44-pin package identity （对比 ICL7136CQH+TD)
设计说明
Treat the analog input, reference, and timing networks as a single high-impedance measurement section. Keep those traces short, avoid routing display-drive outputs beneath them, and place associated bypass capacitors close to the intended supply pins. Verify the completed layout against the manufacturer application circuit because a dual-slope converter can be sensitive to source impedance, leakage, and coupling from the display outputs.
Do not select a replacement solely because it has 44 terminals. Compare the numbered pin assignments, reference-voltage requirements, conversion timing, LCD common and segment outputs, and supply limits. The related ICL7136CQH+TD and ICL7107CQH+TD entries use the same 44-pin package family, but the ICL7107 is identified as an LED-display-driver variant, so an apparent footprint match may still require display-interface changes.
Budget the converter and LCD together because direct display drive adds load beyond the bare ADC function. Confirm the converter's operating and reference voltages, LCD logic levels, and expected display-update pattern from the manufacturer datasheet. If the design uses battery power, calculate average consumption over conversion and display phases rather than relying only on the low-power product designation.
Use a grounded plane that supports the analog reference network without creating long return paths through switching or display currents. Place external timing and reference components according to the manufacturer's recommended layout, keep unused inputs in defined states, and check clock or timing-pin connections against the exact suffix. These steps reduce measurement error and prevent a mechanically compatible board from behaving differently after substitution.
合规信息
The verified component listing explicitly identifies the ICL7137CQH as RoHS compliant and classifies it as commercial grade. No verified information establishes REACH, lead-free, halogen-free, conflict-minerals, or automotive qualification status.
