Microchip Technology 48L512T-I/SN

Overview

48L512T-I/SN from Microchip Technology Inc. is a 512-Kbit serial EERAM integrating a 65,536 × 8-bit SRAM core with cell-based EEPROM backup, SPI interface (up to 66 MHz), and automatic power-loss data retention. It operates from 2.7V–3.6V across –40°C to +85°C and uses an external VCAP capacitor for seamless SRAM-to-EEPROM store/recall during brown-out events. Used in industrial control logging and metering systems requiring nonvolatile SRAM behavior without software intervention.

For engineers reviewing the 48L512T-I/SN datasheet, 48L512T-I/SN pinout, 48L512T-I/SN application, or 48L512T-I/SN equivalent, key selection criteria include symmetrical SPI read/write timing, hibernate current ≤3 μA at 85°C, AutoStore trip voltage (2.30–2.65 V), 100,000 backup cycles, and 8-lead SOIC package compatibility with legacy serial memory footprints.

Technical Context

The 48L512T-I/SN implements a dual-memory architecture where the SRAM array is fully accessible via standard SPI Mode 0/3 commands (MSb-first, rising-edge latch/falling-edge output), while the EEPROM backup layer operates transparently-triggered solely by VCC monitoring circuitry. Its STATUS register includes volatile WEL and RDY/BSY bits plus nonvolatile BP[1:0] block protection and ASE bit.

Power management relies on VCAP pin (3) with 47–100 μF external capacitor: during VCC drop below 2.30–2.65 V, the device isolates VCC, switches to VCAP-supplied power, and completes parallel SRAM→EEPROM transfer in ≤10 ms; on power-up, recall occurs in ≤200 μs before normal operation resumes.

Key Specifications

Pinout & Package

48L512T-I/SN is housed in an 8-lead SOIC package (3.9 mm × 4.9 mm, 1.27 mm pitch), pin-compatible with industry-standard serial memory footprints. The VCAP pin requires a dedicated 47–100 μF/6.3V+ capacitor connected to VSS for autonomous backup operation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar serial nonvolatile memory applications.

Compared with 48L512T-I/SN, the 48LM01T-I/SO offers double density in identical footprint for scalable logging, while the FM25V05-G trades guaranteed 100-year retention for capacitor-free simplicity and lower active power - making each suitable for distinct reliability vs. integration trade-offs.

Availability

48L512T-I/SN is available at Aetrix Electronics and suitable for industrial data loggers, smart metering systems, and PLC I/O modules requiring stable component supply with guaranteed long-term availability and traceable sourcing.

Supply support for 48L512T-I/SN 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 U.S.-based semiconductor company specializing in microcontrollers, analog devices, and memory solutions for industrial, automotive, and communications markets.

The 48L512T-I/SN belongs to Microchip's EERAM product line, designed specifically to replace battery-backed SRAM and nvSRAM in applications demanding zero-maintenance, high-endurance, and guaranteed data retention without external support components.

FAQ

What is the function of the VCAP pin on the 48L512T-I/SN?

The VCAP pin (Pin 3) connects to an external 47–100 μF capacitor that supplies hold-up energy during VCC collapse. When system voltage drops below 2.30–2.65 V, the 48L512T-I/SN isolates VCC and uses stored charge from the VCAP capacitor to complete SRAM-to-EEPROM transfer within 10 ms. This ensures data persistence without external power sources or firmware involvement.

Does the 48L512T-I/SN require a write-enable command before every SRAM write operation?

Yes, the 48L512T-I/SN requires execution of the WREN (06h) instruction to set the Write Enable Latch (WEL) bit before any WRITE, WRSR, or WRNUR command. The WEL bit resets to '0' after each write completes, power-up, or WRDI execution - enforcing explicit write-enable discipline to prevent accidental overwrites.

Can the 48L512T-I/SN operate with SPI Mode 1 or Mode 2?

No, the 48L512T-I/SN supports only SPI Modes 0 and 3 - defined by data latched on rising SCK edge and output on falling SCK edge. Modes 1 and 2 (data latched on falling edge) are not supported. The SCK idle state must match between CS assertion and deassertion: low for Mode 0, high for Mode 3.

How does the HOLD pin affect ongoing SRAM write cycles on the 48L512T-I/SN?

The HOLD pin suspends SPI communication but does not interrupt active internal operations. If a WRITE command is in progress when HOLD is asserted, the 48L512T-I/SN completes the SRAM write before entering hold state. HOLD only pauses clocked instruction/address/data transfer - it never aborts or stalls the underlying memory transaction.

What is the purpose of the 16-byte nonvolatile user space in the 48L512T-I/SN?

The 16-byte nonvolatile user space provides a dedicated, separately addressable region writable via WRNUR and readable via RDNUR commands. Unlike the main SRAM array, this space is copied to nonvolatile memory simultaneously with SRAM and STATUS register during AutoStore or STORE commands - enabling secure storage of calibration constants, device IDs, or security keys independent of application data.