Microchip Technology 47L16-E/ST

Overview

47L16-E/ST from Microchip Technology is a 16 Kbit (2,048 × 8) I²C serial EERAM combining volatile SRAM with nonvolatile EEPROM backup. It features automatic power-loss store/recall via external VCAP capacitor, hardware Store pin (HS), and software-controlled Store/Recall commands. With 1 MHz I²C interface, Schmitt-trigger inputs, and industrial temperature range (−40°C to +85°C), it serves as persistent memory in embedded controllers and sensor nodes requiring data retention across power cycles.

For engineers reviewing the 47L16-E/ST datasheet, 47L16-E/ST pinout, 47L16-E/ST application, or 47L16-E/ST equivalent, key selection criteria include SRAM-to-EEPROM store time (25 ms max), Auto-Store trip voltage (2.4–2.6 V), software write protection granularity (down to 1/64 array), EEPROM endurance (>1 million cycles), and compatibility with standard I²C host controllers including PIC® MCUs.

Technical Context

The 47L16-E/ST implements a dual-memory architecture: a 2,048 × 8-bit SRAM array for high-speed read/write access and a matching EEPROM array for nonvolatile backup. Store and Recall operations are triggered either automatically on VCC fall below VTRIP (2.4–2.6 V) or manually via HS pin assertion or I²C software commands (0x33 for Store, 0xDD for Recall).

Its I²C interface supports 100 kHz, 400 kHz, and 1 MHz clock rates with zero-cycle-delay reads/writes, Schmitt-triggered SDA/SCL inputs, and cascading support for up to four devices on one bus. The STATUS register (address 0x00) provides volatile AM bit tracking, nonvolatile BP<2:0> block protection, ASE enable control, and EVENT flag for HS pin detection.

Key Specifications

Pinout & Package

47L16-E/ST is housed in an 8-lead SOIC package (ST suffix), with 1.27 mm pitch, JEDEC MS-012AC compliant, and rated for industrial temperature range (−40°C to +85°C).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar EERAM applications.

Compared with 47L16-I/ST, the 47L16-E/ST adds extended-temperature reliability and higher VTRIP margin for robust Auto-Store activation; compared with FM24V10-G, it trades F-RAM endurance for integrated power-loss management logic and hardware event detection - making it optimal for cost-sensitive, capacitor-assisted brown-out recovery systems.

Availability

47L16-E/ST is available at Aetrix Electronics and suitable for smart metering, industrial PLCs, automotive body control units, and medical sensor nodes requiring stable component supply across extended temperature ranges and multi-year production lifecycles.

Supply support for 47L16-E/ST 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 embedded and industrial markets.

The 47L16-E/ST belongs to Microchip's EERAM product line, designed specifically to replace battery-backed SRAM and simplify nonvolatile data logging in resource-constrained I²C systems.

FAQ

What is the function of the VCAP pin on the 47L16-E/ST?

The VCAP pin on the 47L16-E/ST connects to an external capacitor (minimum 10 µF) that supplies energy during power loss to complete automatic Store of SRAM contents to EEPROM. If Auto-Store is disabled, VCAP must be tied to VCC to prevent EEPROM corruption. The 47L16-E/ST uses this pin to detect VCC drop below 2.4–2.6 V and initiate Store within 25 ms.

How does the 47L16-E/ST differ from standard I²C EEPROMs?

Unlike standard I²C EEPROMs, the 47L16-E/ST integrates a parallel-access SRAM array with instantaneous read/write performance and automatic background EEPROM backup. It supports zero-cycle-delay I²C transfers, hardware Store triggering via HS pin, and software-configurable write protection - features absent in conventional EEPROMs like 24AA128. The 47L16-E/ST eliminates page-write delays and wear-leveling complexity.

Can the 47L16-E/ST be used without an external capacitor?

Yes, the 47L16-E/ST can operate without an external capacitor only if Auto-Store is disabled (ASE = 0) and VCAP is hard-wired to VCC. In this mode, Store and Recall must be initiated manually via HS pin or I²C software commands (0x33/0xDD). However, power-loss data retention is not guaranteed - making external VCAP mandatory for true nonvolatile operation in uncontrolled power environments.

What is the maximum I²C clock frequency supported by the 47L16-E/ST?

The 47L16-E/ST supports I²C clock frequencies up to 1 MHz under 2.7–3.6 V operation, with guaranteed timing margins for THIGH/TLOW ≥500 ns and rise/fall times ≤300 ns. This allows high-throughput data logging - for example, writing 256 bytes in under 3 ms - while maintaining compatibility with standard I²C controllers including PIC® MCU peripherals and Linux I²C drivers.

How is write protection configured on the 47L16-E/ST?

Write protection on the 47L16-E/ST is configured through the BP<2:0> bits in the STATUS register (address 0x00), allowing granular protection of SRAM blocks from 1/64 (upper 32 bytes) to the full 2,048-byte array. Protection is nonvolatile and persists across power cycles. Attempts to write to protected regions result in NACK - enabling fail-safe configuration storage in safety-critical applications using the 47L16-E/ST.