Microchip Technology 47L16-I/P

Overview

47L16-I/P from Microchip Technology is a 16 Kbit (2,048 × 8) serial EERAM combining volatile SRAM with nonvolatile EEPROM backup, operating at 2.7–3.6 V and supporting I²C up to 1 MHz. It enables automatic power-loss data retention via external capacitor-triggered store, hardware/manual/software-initiated store/recall, and provides infinite SRAM write cycles with >1 million EEPROM store cycles. It is used in industrial control systems requiring persistent memory without battery backup.

For engineers reviewing the 47L16-I/P datasheet, 47L16-I/P pinout, 47L16-I/P application, or 47L16-I/P equivalent, this page delivers verified electrical specs, I²C timing constraints, SRAM-EEPROM coherency behavior, Auto-Store trip voltage (2.4–2.6 V), and real-world use cases in programmable logic controllers and sensor node firmware storage.

Technical Context

The 47L16-I/P implements a dual-memory architecture where SRAM serves as fast read/write working memory and EEPROM preserves data across power cycles. Its I²C interface uses Schmitt-trigger inputs, supports cascading up to four devices, and enforces strict bus timing (e.g., THIGH/TLOW ≥ 500 ns, TAA ≤ 400 ns).

Store and recall operations are managed through three independent mechanisms: automatic (triggered by VCC falling below VTRIP = 2.4–2.6 V), hardware (via HS pin pulse ≥150 ns), and software (via COMMAND register writes 0x33/0xDD). The STATUS register (address 0x00) tracks array modification (AM bit), enables Auto-Store (ASE), configures block protection (BP2–BP0), and latches external events (EVENT bit).

Key Specifications

Pinout & Package

47L16-I/P is supplied in an 8-lead PDIP (Plastic Dual In-line Package) with 0.3-inch body width, suitable for through-hole prototyping and legacy industrial PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with FM24V10-G and AT24C128C-SSHL-T, the 47L16-I/P uniquely combines SRAM-speed access, capacitor-based autonomous store, hardware event detection, and configurable write protection - making it optimal for real-time embedded systems where deterministic nonvolatility is architecturally critical.

Availability

47L16-I/P is available at Aetrix Electronics and suitable for industrial control systems, smart sensor nodes, HMI interfaces, and portable test equipment requiring stable component supply and long-term lifecycle support.

Supply support for 47L16-I/P 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 infrastructure.

The 47L16-I/P belongs to Microchip's EERAM product line, designed specifically for applications needing seamless, low-overhead nonvolatile memory replacement for battery-backed SRAM - targeting industrial, automotive, and IoT edge devices.

FAQ

What is the function of the VCAP pin on the 47L16-I/P?

The VCAP pin on the 47L16-I/P connects to an external capacitor (8–10 µF) that supplies hold-up energy during power loss, enabling automatic SRAM-to-EEPROM store. If Auto-Store is disabled (ASE = 0), VCAP must be tied to VCC. Leaving VCAP floating risks EEPROM corruption during brownout events. The 47L16-I/P monitors VCAP voltage against VTRIP (2.4–2.6 V) to initiate store.

How does the 47L16-I/P handle write protection of its SRAM array?

The 47L16-I/P uses three nonvolatile BP2–BP0 bits in the STATUS register to configure software write protection across eight ranges - from no protection to full 16 Kbit lock. For example, BP2:BP0 = 101 protects the upper 1/4 (0x600–0x7FF). Protected blocks reject write attempts with NACK, preserving critical data like calibration constants without requiring external logic. This protection persists across power cycles.

Can the 47L16-I/P operate without an external capacitor?

Yes, the 47L16-I/P can operate without an external capacitor on VCAP only if Auto-Store is disabled (ASE bit = 0 in STATUS register) and VCAP is hard-wired to VCC. In this mode, store/recall must be initiated manually via HS pin or software commands. Omitting the capacitor while enabling Auto-Store risks incomplete EEPROM writes and data corruption during power loss - a condition explicitly prohibited in the 47L16-I/P datasheet.

What is the maximum I²C clock frequency supported by the 47L16-I/P?

The 47L16-I/P supports I²C clock frequencies up to 1 MHz under specified conditions (VCC = 2.7–3.6 V, TA = –40°C to +85°C). This allows high-speed configuration loading and status polling in time-critical applications. Timing parameters such as THIGH/TLOW (≥500 ns), TAA (≤400 ns), and TF/TR (≤300 ns) must be met; standard-mode (100 kHz) and fast-mode (400 kHz) are also fully compliant.

How does the EVENT bit in the STATUS register work on the 47L16-I/P?

The EVENT bit (bit 0) in the 47L16-I/P STATUS register is a nonvolatile flag set automatically when the HS pin is driven high during valid operation (VCAP ≥ VTRIP and not during Store/Recall). It remains set until cleared by a STATUS register write. This enables the host MCU to detect and log external events - such as button presses or safety interlock triggers - even after power cycles, without requiring continuous polling of the HS pin.