Microchip Technology MCP98242T-CE/MC

Overview

MCP98242T-CE/MC from Microchip Technology is a JEDEC JC42.4-compliant digital temperature sensor with integrated 256-byte serial EEPROM, designed for DDR memory module SPD applications. It delivers ±0.5°C (typ.) accuracy from +75°C to +95°C, operates from 3.0V to 3.6V, draws only 200 µA typical active current and 3 µA max shutdown current, and interfaces via I²C/SMBus at up to 100 kHz.

For engineers reviewing the MCP98242T-CE/MC datasheet, MCP98242T-CE/MC pinout, MCP98242T-CE/MC application, or MCP98242T-CE/MC equivalent, this page provides verified technical context, package mapping, register-level functionality, thermal event configuration, and SPD EEPROM write-protection behavior - all specific to the TDFN-8 variant with exposed pad.

Technical Context

The MCP98242T-CE/MC integrates a band-gap temperature sensor and delta-sigma ADC with user-programmable registers for boundary-triggered event output, critical trip lock, and resolution selection (0.25°C default). Its dual-function architecture supports both real-time thermal monitoring and SPD data storage in a single 8-pin TDFN package.

It implements separate address spaces for sensor (0011xxx) and EEPROM (1010xxx), supports permanent and reversible software write-protection on lower 128 bytes (00h–7Fh), and features an open-drain Event pin configurable as comparator, interrupt, or critical alert - all compliant with SMBus timeout (40 ms typ.) and I²C timing specifications.

Key Specifications

Pinout & Package

Package: 8-lead TDFN (2 mm × 3 mm), exposed thermal pad (EP) internally connected to GND - requires PCB thermal pad connection for optimal thermal response (θ_JA = 41°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar temperature sensor + SPD EEPROM applications.

Compared with AT30TS74-MA8-Y and MCP9808-E/MS, the MCP98242T-CE/MC uniquely combines JEDEC-compliant thermal sensing, SPD EEPROM, and programmable event output in one TDFN-8 package - eliminating inter-component timing skew and simplifying DIMM-level firmware integration.

Availability

MCP98242T-CE/MC is available at Aetrix Electronics and suitable for DDR3/DDR4 memory module manufacturing, server OEM qualification, and industrial embedded DIMM design requiring stable component supply, JEDEC compliance, and dual-function integration.

Supply support for MCP98242T-CE/MC includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology Inc. is a leading provider of microcontrollers, analog components, and memory solutions, with core expertise in embedded control and thermal management ICs.

The MCP98242 product line was engineered specifically for JEDEC JC42.4-compliant memory module thermal monitoring and SPD data storage - targeting DDR2/DDR3/DDR4 DIMM, SO-DIMM, and RDIMM applications.

FAQ

What is the primary function of the MCP98242T-CE/MC in a memory module?

The MCP98242T-CE/MC serves a dual role: it acts as a JEDEC JC42.4-compliant digital temperature sensor for real-time thermal monitoring of DDR memory modules, and as a 256-byte serial EEPROM for storing Serial Presence Detect (SPD) data such as vendor ID, timing parameters, and module configuration. Its integrated design eliminates the need for separate sensor and SPD components on DIMMs.

Does the MCP98242T-CE/MC support write-protection for SPD data?

Yes, the MCP98242T-CE/MC supports both permanent and reversible software write-protection for the lower 128 bytes (00h–7Fh) of its EEPROM - precisely where JEDEC mandates critical SPD fields like manufacturer ID and memory timings. The upper 128 bytes (80h–FFh) remain freely writable for user-defined data, and protection is enforced via dedicated register bits and high-voltage write-enable sequences.

How is the Event output pin configured on the MCP98242T-CE/MC?

The Event pin on the MCP98242T-CE/MC is an open-drain output whose behavior is fully programmable via the CONFIG register. It can be set as an active-low or active-high comparator output for thermostat use, as a temperature event interrupt for microprocessor systems, or as a critical temperature alert. Configuration includes polarity selection, hysteresis (0°C to 6°C), and lock controls for trip registers - all accessible over I²C without hardware changes.

What I²C address does the MCP98242T-CE/MC use for temperature sensor access?

The MCP98242T-CE/MC uses a 7-bit I²C slave address of 0011xxx (binary), where the three LSBs (xxx) are determined by the logic levels on pins A2, A1, and A0. This allows up to eight MCP98242T-CE/MC devices to share the same I²C bus. The EEPROM portion uses a separate fixed address (1010xxx), ensuring independent access to sensor and SPD functions without address conflict.

Is the MCP98242T-CE/MC compatible with DDR4 memory modules?

Yes, the MCP98242T-CE/MC is explicitly designed for JEDEC JC42.4 Mobile Platform Memory Module Thermal Sensor Component compliance, which applies to DDR2, DDR3, and DDR4 DIMMs. Its accuracy specification (±0.5°C typ. from +75°C to +95°C), voltage range (3.0–3.6V), and register map align with DDR4 SPD and thermal monitoring requirements defined in JEDEC standards.