MCP9805-BE/ST

Overview

The MCP9805-BE/ST is a digital temperature sensor designed for mobile platform memory module thermal sensing, meeting JEDEC JC42.4 standards. It operates within a voltage range of 3.0V to 3.6V and features a 2-wire SMBus/I2C compatible interface with a maximum clock frequency of 100 kHz. The device provides an accuracy of ±1°C (max.) from +75°C to +95°C and ±2°C (max.) from +40°C to +125°C. It utilizes a Delta-Sigma ADC with a typical conversion time of 65 ms at 0.25 °C/LSb resolution. Operating current is typically 200 µA, reducing to 0.1 µA in shutdown mode.

Feature Summary

• Complies with JEDEC JC42.4 standard for mobile platform memory module thermal sensing applications
• Features user-programmable temperature monitor boundaries and critical temperature output capabilities
• Supports up to eight sensors on a single serial bus via standard I2C/SMBus protocol
• Includes open-drain event output configurable as comparator or interrupt signal

Applications

• Dual In-line Memory Module (DIMM) thermal monitoring
• Personal Computers (PCs) and Servers
• Hard Disk Drives and Other PC Peripherals
• General Purpose Temperature Sensor

Procurement Notes

Verify the specific ordering suffix matches the required package type, as the BE/ST designation corresponds to the TSSOP-8 package. Confirm that the operating environment stays within the specified -40°C to +125°C range to ensure accurate performance. Ensure the power supply voltage remains strictly between 3.0V and 3.6V to prevent damage or malfunction. Check for RoHS compliance documentation if environmental regulations apply to the final assembly.

Selection Notes

Select this component when JEDEC JC42.4 compliance is mandatory for memory subsystems. Choose the TSSOP-8 package variant specifically for surface-mount requirements fitting the /ST suffix. Consider the 0.25 °C/LSb default resolution for high-precision needs. Evaluate the low shutdown current if power management during idle states is a critical design constraint.

Part Context

This device belongs to Microchip's line of digital temperature sensors designed for system-level thermal management. It integrates a bandgap sensor and delta-sigma ADC into a compact form factor. The series supports multi-zone monitoring through addressable slave pins, allowing complex thermal architectures without additional multiplexing hardware.

Replacement Considerations

Public confirmed substitute part numbers: MCP9805-BEMC, MCP9805-BEST.