Microchip Technology MCP98242T-BE/MUY

Overview

MCP98242T-BE/MUY from Microchip Technology is a JEDEC JC42.4-compliant digital temperature sensor with integrated 256-byte serial EEPROM for SPD applications, operating from −40°C to +125°C with ±0.5°C typical accuracy (75–95°C), 200 µA typical operating current, and I²C/SMBus interface. It serves as a memory-module thermal monitor in DDR DIMMs.

For engineers reviewing the MCP98242T-BE/MUY datasheet, MCP98242T-BE/MUY pinout, MCP98242T-BE/MUY application, or MCP98242T-BE/MUY equivalent, key selection factors include its dual-function architecture (sensor + SPD EEPROM), programmable event output polarity and hysteresis, shutdown mode (3 µA max), and TSSOP-8 package compatibility with JEDEC memory module layouts.

Technical Context

The MCP98242T-BE/MUY integrates a bandgap-based temperature sensor with a ΔΣ ADC and user-programmable registers for boundary monitoring, critical trip detection, and resolution selection (0.0625°C to 0.5°C). Its EEPROM is partitioned into permanently or reversibly write-protected lower 128 bytes (00h–7Fh) and unprotected upper 128 bytes (80h–FFh).

It implements an open-drain Event output configurable as active-low/high comparator or interrupt, with lockable TUPPER/TLOWER/TCRIT registers and hysteresis settings (0°C, 1.5°C, 3°C, 6°C). The device supports up to eight devices on one I²C bus using A0–A2 address pins and complies with SMBus time-out (40 ms typ.) and electrical specifications at 3.0–3.6 V.

Key Specifications

Pinout & Package

Package: 8-pin TSSOP (JEDEC MO-153, 3.0 mm × 4.4 mm), lead-free, RoHS-compliant, with exposed pad internally connected to GND.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT30TS75-MA8-Y and LM75BIMM/NOPB, the MCP98242T-BE/MUY uniquely integrates JEDEC-compliant thermal sensing, SPD EEPROM with hardware write-protection, and fully programmable event logic - making it the only drop-in solution for DDR memory modules requiring JC42.4 certification.

Availability

MCP98242T-BE/MUY is available at Aetrix Electronics and suitable for DDR memory modules, laptop thermal management systems, and server riser card designs requiring stable component supply, JEDEC compliance, and long-term SPD data integrity.

Supply support for MCP98242T-BE/MUY 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, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The MCP98242 product line was designed specifically for JEDEC JC42.4-compliant memory module thermal monitoring and Serial Presence Detect (SPD) data storage in DDR DIMMs, balancing precision, low power, and robust EEPROM security.

FAQ

What is the primary application of the MCP98242T-BE/MUY?

The MCP98242T-BE/MUY is primarily used as a JEDEC JC42.4-compliant temperature sensor and SPD EEPROM in DDR memory modules. It provides accurate thermal monitoring from −40°C to +125°C and stores vendor-specific SPD data in its 256-byte EEPROM. Its TSSOP-8 package and I²C interface make it ideal for DIMM slot integration, and the MCP98242T-BE/MUY supports programmable trip points, hysteresis, and event output configurations required by memory subsystems.

Does the MCP98242T-BE/MUY support I²C and SMBus protocols?

Yes, the MCP98242T-BE/MUY features a 2-wire interface fully compatible with standard-mode I²C and SMBus protocols. It operates at 10–100 kHz clock speeds, supports ACK/NAK handshaking, and implements SMBus time-out (40 ms typical). The MCP98242T-BE/MUY also meets SMBus electrical specifications at 3.0–3.6 V supply, including open-drain Event output and SDA/SCL input thresholds, ensuring interoperability with host controllers in memory and embedded systems.

How is the EEPROM in the MCP98242T-BE/MUY protected against unintended writes?

The MCP98242T-BE/MUY EEPROM includes dual write-protection schemes: permanent write-protection (PWP) and software-reversible write-protection (SWP) for the lower 128 bytes (00h–7Fh), which store critical SPD vendor data. The upper 128 bytes (80h–FFh) remain unprotected for general-purpose use. Protection is enabled via high-voltage pulses (8–12 V) applied to the A0 pin, and SWP can be toggled in-system without hardware changes. This ensures SPD data integrity while allowing flexible field updates where needed - a key feature of the MCP98242T-BE/MUY.

What temperature accuracy does the MCP98242T-BE/MUY deliver across its operating range?

The MCP98242T-BE/MUY delivers ±0.5°C typical / ±1°C maximum accuracy from +75°C to +95°C, meeting JEDEC JC42.4 requirements for memory thermal sensors. Over +40°C to +125°C, accuracy is ±1°C typical / ±2°C maximum; over −20°C to +125°C, it is ±2°C typical / ±3°C maximum. At −40°C, accuracy is −2°C typical. These values are measured at 3.0–3.6 V supply and reflect actual characterization data - not estimates - and define the real-world thermal measurement fidelity of the MCP98242T-BE/MUY.

Can the MCP98242T-BE/MUY operate in shutdown mode, and what is its current draw?

Yes, the MCP98242T-BE/MUY supports a software-configurable shutdown mode that disables the temperature sensor's bandgap circuit and ADC while retaining register contents and EEPROM accessibility. In this state, the MCP98242T-BE/MUY draws ≤3 µA (maximum) at 3.0–3.6 V, enabling ultra-low-power thermal monitoring in battery-backed or energy-constrained systems. The ambient temperature register (TA) holds the last valid reading until wake-up, and conversion resumes within 65–125 ms after exiting shutdown - a core low-power feature of the MCP98242T-BE/MUY.