MAX136CMH - 3½-Digit LCD ADC with Hold | Analog Devices
N.º da peça: MAX136CMH ✓ AtivoMAX136CMH Visão geral
An analog-to-digital converter, or ADC, converts an analog input voltage into a numeric representation for measurement, display, or further processing. The MAX136 belongs to the family of low-power, high-resolution integrating converters used in digital panel meters, laboratory instruments, weighing systems, and temperature-measurement equipment. Its 3½-digit architecture provides 1999-count resolution, while the high input impedance minimizes loading of the sensing circuit.
The MAX136's most distinctive feature is a Hold pin that can freeze or retain a conversion result. Unlike the Maxim ICL7136, the MAX136 includes this function, allowing a reading to remain stable while it is inspected or transferred. The device also directly drives nonmultiplexed LCD outputs, eliminating separate LCD driver hardware when the selected display uses the compatible segment arrangement.
Because the MAX136 uses a dual-slope integration technique, its performance depends on accurate reference and integration components. The manufacturer's datasheet describes the MAX136 as pin compatible with the Maxim ICL7136 after minor external component changes. That compatibility involves reviewing the Hold implementation and associated passive components rather than assuming an unconditional, board-for-board substitution.
Typical uses include digital laboratory meters, industrial panel indicators, environmental monitors, laboratory scales, process readouts, and portable instruments. In each application, the high-input-impedance measurement stage can be paired with a resistive divider or sensor bridge without loading the source significantly. The LCD output reduces system complexity in designs centered on a local numeric display.
For a new design, follow the reference, integration, analog-input, and display connections in the manufacturer datasheet. Pay particular attention to bypass capacitors, input filtering, PCB cleanliness, and the Hold timing. When replacing an ICL7136-based assembly, review the changed external components and verify the LCD segment mapping rather than relying on package similarity alone.
This page combines the MAX136CMH device identity, package information, application guidance, design cautions, and available drop-in candidates into an engineering-focused guide. It also distinguishes confirmed family variants from a replacement that requires external circuit changes, helping designers make a controlled compatibility decision before committing a PCB revision.
Alternativas drop-in para MAX136CMH — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
MAX136CMH+D
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MAX136CMH+TD
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MAX136CMH+
✅ Drop-In ⚠️ Especificações não verificadas📋 Alternativa de referência (fora do catálogo)
MAX136CMH Classificações máximas e características elétricas
| ADC Type | Monolithic dual-slope analog-to-digital converter |
| Resolução | 3½ digits, 1999 counts |
| Input Type | Single-ended analog voltage input |
| Display Output | Direct nonmultiplexed LCD drive |
| Hold Function | Yes |
| Encapsulamento | 44-pin MQFP, 10 mm x 10 mm |
| Terminal Count | 44 terminals |
| Terminal Form | Gull-wing leads |
| Package Shape | Square |
| Tipo de montagem | Surface mount |
| Production Status | Production |
Guia de Configuração de Pinos do MAX136CMH square
Configuração de pinos para MAX136CMH (pacote square). Este componente analógico possui pinos de entrada, saída e alimentação. Consulte o datasheet do fabricante para configurações de offset null, compensação e pino de enable. Ideal para circuitos de condicionamento de sinal e amplificadores.
Nenhum dado detalhado de pinagem disponível para MAX136CMH.
Consulte a ficha técnica para a configuração completa dos pinos.
Aplicações típicas
MAX136CMH é adequado para 6 aplicaçãos: Digital Laboratory Panel Meter, Environmental Monitoring Instrument, Portable Weighing Scale Readout, Process Monitoring Readout, Portable Temperature Indicator, Handheld Test and Measurement Meter.
Digital Laboratory Panel Meter
The MAX136CMH fits a standalone laboratory meter because it combines a 3½-digit, 1999-count conversion system with direct nonmultiplexed LCD drive. The high-impedance measurement input helps preserve the signal from a resistive divider or sensor interface, while the Hold function can stabilize the reading during adjustment or observation. Place the reference and bypass components close to the device and follow the manufacturer's application circuit for display-drive and analog filtering details.
Recomendado
Environmental Monitoring Instrument
The MAX136CMH is suitable for a local environmental readout that measures a scaled sensor voltage and displays the result on a nonmultiplexed LCD. Its 3½-digit format provides 1999-count resolution without requiring a separate display-driver IC. The high-impedance input reduces errors in resistive probes, while Hold allows the displayed value to remain fixed during sample checks. Verify the input range, reference network, segment mapping, and calibration procedure in the manufacturer datasheet.
Recomendado
Portable Weighing Scale Readout
The MAX136CMH can provide the local numeric readout for a compact weighing-scale front panel. A load-cell signal can be conditioned into a voltage compatible with the converter, and the 3½-digit display can communicate a 1999-count measurement directly. The Hold pin is useful when a value must remain stable during inspection. The design must follow the recommended input filter and reference layout to prevent noise or drift from appearing as measurement variation.
Recomendado
Process Monitoring Readout
The MAX136CMH is useful in industrial process-monitoring equipment that converts a conditioned sensor signal into a local 3½-digit LCD indication. The integrated display drive simplifies instrument construction, and the high-impedance input helps avoid loading the measuring circuit. The Hold function supports temporary freezing of a reading during adjustment. For reliable operation, isolate the analog input from switching nodes, maintain the recommended bypass arrangement, and confirm the display's nonmultiplexed segment configuration.
Recomendado
Portable Temperature Indicator
The MAX136CMH can serve as the display and conversion engine in a portable temperature indicator driven by a resistive or ratiometric sensor. Its 3½-digit readout provides useful resolution for panel-style instruments, while the high-impedance input helps maintain sensor accuracy. Because the converter drives a nonmultiplexed LCD directly, the display interface remains compact. Review the input common-mode range, reference stability, and calibration method before selecting component values around the MAX136CMH.
Recomendado
Handheld Test and Measurement Meter
The MAX136CMH suits a handheld meter where low component count and a direct LCD readout are priorities. Its low-power 3½-digit architecture integrates measurement conversion and display drive in one 44-pin MQFP, while the Hold input lets an operator retain a measurement. The converter can be paired with resistive dividers or buffered sensor inputs, provided the electrical limits and reference requirements are followed. Layout work should emphasize short analog traces, stable grounding, and correct LCD segment assignment.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para MAX136CMH — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | MAX136CMH+D | MAX136CMH+TD | MAX136CMH+ |
|---|---|---|---|---|
| Package | 44-MQFP (10 mm x 10 mm) | 44-MQFP (10 mm x 10 mm) | 44-MQFP (10 mm x 10 mm) | 44-MQFP (10 mm x 10 mm) |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Converter Type | Monolithic dual-slope ADC | MAX136 family dual-slope ADC | MAX136 family dual-slope ADC | MAX136 family dual-slope ADC |
| Resolution | 3½ digits, 1999 counts | 3½ digits | 3½ digits | 3½ digits |
| Hold Function | Yes | Yes | Yes | Yes |
| LCD Drive | Direct nonmultiplexed LCD drive | Direct nonmultiplexed LCD drive | Direct nonmultiplexed LCD drive | Direct nonmultiplexed LCD drive |
| Pin Compatibility | MAX136 family, 44-pin MQFP | Same MAX136 family footprint | Same MAX136 family footprint | Same MAX136 family footprint |
Principais diferenciais
- Adds a dedicated Hold function to the compatible MAX136 family (vs ICL7136CMH)
- Integrates nonmultiplexed LCD drive with 3½-digit conversion (vs ICL7136CMH)
- Direct 44-MQFP family sourcing within the MAX136 line (vs ICL7136CMH)
Notas de projeto
Route the analog input and reference paths as short, quiet traces, with the associated external components placed close to the MAX136CMH pins. Keep LCD output routing separated from the measurement input where practical, and avoid sharing high-current return paths directly beneath the converter. Start from the manufacturer's application circuit and preserve the recommended grounding topology.
Do not treat ICL7136CMH as a board-for-board replacement without reviewing the external-component changes associated with the MAX136 Hold function. Confirm the LCD segment mapping, Hold timing, reference network, and bypass connections. A matching 44-pin package establishes physical compatibility, but it does not by itself prove identical system behavior.
The high-impedance measurement input can pick up leakage and noise if the surrounding PCB is not clean. Use the recommended input filtering, guard or shield techniques where appropriate, and keep moisture or contamination away from the analog section. Check the reference potential and input common-mode limits against the operating range before finalizing the sensor interface.
Follow the manufacturer guidance for supply bypassing and clock-generation components rather than selecting values solely from generic dual-slope ADC examples. Decoupling capacitors should be placed at the relevant supply pins with short ground returns. Verify the actual supply range, clock amplitude, and reference voltage before committing the power subsystem.
Informações de conformidade
The MAX136 family is listed as production, but no explicit RoHS, REACH, lead-free, halogen-free, or conflict-minerals declarations were identified for the exact MAX136CMH ordering code.
