48LM01-I/SM

Overview

The Microchip Technology 48LM01-I/SM is a 1-Mbit (131,072 x 8 bit) Serial EERAM featuring an SRAM core with hidden EEPROM backup. It operates on a high-speed SPI interface up to 66 MHz and supports Industrial temperature ranges from -40°C to +85°C. The device requires a supply voltage between 2.7V and 3.6V and includes a VCAP pin for external capacitor connection to support automatic data preservation during power disruptions.

Feature Summary

• Provides unlimited read and write cycles through symmetrical SRAM timing while maintaining nonvolatile data retention via internal EEPROM backup.
• Features invisible-to-user automatic data transfers that mirror the SRAM array cell-for-cell upon power disruption or brown-out events.
• Includes a dedicated 16-byte nonvolatile user space accessible via specific commands for storing configuration data independently of the main array.

Applications

• Data logging systems requiring persistent storage without complex wear-leveling algorithms
• Industrial control applications needing reliable parameter retention during unexpected power loss
• Embedded systems utilizing standard SPI buses for memory expansion

Procurement Notes

Verify the specific suffix 'I/SM' corresponds to the Industrial temperature range (-40°C to +85°C) and the 8-lead SOIJ package type as documented in the official datasheet. Confirm that system designs include the required external capacitor on the VCAP pin to ensure proper AutoStore functionality during power-down events.

Selection Notes

Select this component when designing systems that require true random access memory speeds combined with nonvolatile data retention. Ensure the host controller supports SPI Modes 0 or 3 and can manage the Write Enable Latch sequence. Verify that the application environment stays within the specified voltage and temperature limits to maintain data integrity.

Part Context

This part belongs to the 48L512/48LM01 family of Serial EERAMs. It shares architectural similarities with the 48L512 but offers double the memory density. Both devices utilize the same instruction set and pinout configurations, differing primarily in addressable capacity and physical package variations.

Replacement Considerations

Direct substitutes within the same family include the 48L512 variant, which offers identical functionality with half the memory capacity. Cross-family replacements require careful evaluation of SPI compatibility and voltage levels.

FAQ

How does the device handle data preservation during a power failure?

The device monitors the VCC level internally. If VCC drops below a threshold, it suspends I/O operations and uses energy stored in the external VCAP capacitor to automatically transfer all SRAM data to the hidden EEPROM array.

What is the function of the HOLD pin?

The HOLD pin allows the user to pause serial communication mid-sequence without resetting the clock or losing the current state. It must be held high when not in use.