Microchip Technology 47L16-E/P

Overview

47L16-E/P from Microchip Technology is a 16 Kbit (2,048 × 8) I²C serial EERAM combining volatile SRAM with nonvolatile EEPROM backup. It operates from 2.7V–3.6V, supports up to 1 MHz I²C, and delivers automatic power-loss data retention via external VCAP capacitor. Its circuit role is nonvolatile memory buffering in real-time control systems requiring persistent state storage across power cycles.

For engineers reviewing the 47L16-E/P datasheet, 47L16-E/P pinout, 47L16-E/P application, or 47L16-E/P equivalent, key selection considerations include Auto-Store trip voltage (2.4–2.6 V), 25 ms max Store time, software write protection granularity (down to 1/64 of array), industrial temperature range (–40°C to +85°C), and PDIP-8 package compatibility with legacy through-hole designs.

Technical Context

The 47L16-E/P integrates dual-memory architecture: a 2,048 × 8-bit SRAM array for high-speed read/write access and a matching EEPROM array for nonvolatile backup. Data transfer between them is triggered by power loss (Auto-Store), hardware pulse on HS pin, or software command (0x33 Store / 0xDD Recall).

I²C interface compliance includes 100 kHz/400 kHz/1 MHz modes, Schmitt-trigger inputs on SDA/SCL/HS for noise immunity, and cascading support for up to four devices on one bus. The STATUS register (address 0x00) controls ASE (Auto-Store Enable), BP<2:0> (block protection), and AM (Array Modified) flag-critical for deterministic store eligibility.

Key Specifications

Pinout & Package

47L16-E/P is supplied in an 8-lead PDIP (Plastic Dual In-line Package) with 0.300-inch body width, suitable for through-hole prototyping and legacy PCB assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 47L16-I/P, the 47L16-E/P adds extended temperature operation essential for automotive under-hood placement; versus FM24CL16-G, it retains HS pin control and event flagging at the cost of capacitor dependency and finite EEPROM endurance.

Availability

47L16-E/P is available at Aetrix Electronics and suitable for industrial PLCs, automotive body control modules, medical infusion pumps, and smart energy meters requiring stable component supply with long lifecycle assurance.

Supply support for 47L16-E/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 is a U.S.-based semiconductor company specializing in microcontrollers, analog devices, and memory solutions, with emphasis on reliability and long-term product availability.

The 47L16-E/P belongs to Microchip's EERAM family, designed specifically for applications needing seamless SRAM-like performance with EEPROM-level nonvolatility-targeting industrial control, automotive subsystems, and medical equipment where data survivability is mission-critical.

FAQ

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

The VCAP pin on the 47L16-E/P connects to an external capacitor (minimum 10 µF) that supplies hold-up energy during VCC collapse. When VCC drops below the Auto-Store trip voltage (2.4–2.6 V), the 47L16-E/P uses charge from this capacitor to complete a full SRAM-to-EEPROM store operation within 25 ms. Without VCAP, Auto-Store must be disabled via the ASE bit to prevent data corruption.

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

The 47L16-E/P implements software-configurable write protection via three BP<2:0> bits in the STATUS register (address 0x00). These bits allow locking 1/64 to the entire 2,048-byte SRAM array-e.g., BP<2:0>=001 protects addresses 0x7E0–0x7FF in 47L16-E/P. Protection is nonvolatile and persists across power cycles, preventing accidental overwrites of critical calibration or configuration data.

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

Yes, the 47L16-E/P can operate without an external capacitor on VCAP, but Auto-Store functionality must be disabled by clearing the ASE bit in the STATUS register. In this mode, SRAM data persistence relies solely on manual Store commands (via HS pin or I²C software command 0x33). VCAP must be tied to VCC if omitted, per Microchip's design guidance to avoid EEPROM corruption during uncontrolled power loss.

What is the significance of the EVENT bit in the 47L16-E/P STATUS register?

The EVENT bit (bit 0) in the 47L16-E/P STATUS register is a nonvolatile flag that latches high when the HS pin is driven high during normal operation. It remains set until explicitly cleared via a STATUS register write, enabling host firmware to detect and log external hardware events-such as button presses or sensor triggers-without continuous polling. This reduces I²C bus traffic and CPU overhead in event-driven systems.

How does the 47L16-E/P differ from standard I²C EEPROMs in system design?

Unlike standard I²C EEPROMs, the 47L16-E/P provides concurrent SRAM-like read/write performance (zero-cycle-delay) with background nonvolatile backup. It eliminates EEPROM write latency during active operation, supports byte/sequential access without page boundaries, and offers hardware-triggered store via HS pin-making it ideal for real-time systems where deterministic response and power-fail resilience are mandatory.