Microchip Technology 47C16-I/ST

Overview

47C16-I/ST from Microchip Technology is a 16 Kbit (2,048 × 8) I²C serial EERAM combining volatile SRAM with nonvolatile EEPROM backup. It operates at 4.5V–5.5V, supports up to 1 MHz I²C, and delivers automatic power-loss data retention via VCAP capacitor-assisted store/recall. It serves as a drop-in replacement for battery-backed SRAM in industrial control logging and sensor node memory buffering.

For engineers reviewing the 47C16-I/ST datasheet, 47C16-I/ST pinout, 47C16-I/ST application, or 47C16-I/ST equivalent, key selection criteria include its 25 ms max store time, hardware store pin (HS), software-configurable write protection, Auto-Store Enable (ASE) bit, and AEC-Q100-qualified operation across –40°C to +85°C.

Technical Context

The 47C16-I/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 (4.0–4.4 V), manually via HS pin pulse ≥150 ns, or through software commands written to the COMMAND register (0x55).

I²C interface compliance includes standard-mode (100 kHz), fast-mode (400 kHz), and fast-mode plus (1 MHz) timing, with Schmitt-trigger inputs on SDA/SCL/HS for noise immunity and cascading support for up to four devices on one bus. The STATUS register (0x00) provides real-time tracking of array modification (AM bit), block protection (BP2–BP0), and external event detection (EVENT bit).

Key Specifications

Pinout & Package

47C16-I/ST is housed in an 8-lead TSSOP (Thin Shrink Small Outline Package) with 0.65 mm lead pitch, optimized for space-constrained PCB layouts and automated assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with FM24CL16B and AT24C128C-SSHL-T, the 47C16-I/ST uniquely integrates SRAM speed with EEPROM persistence in a single 5 V-compatible device featuring autonomous power-loss response-reducing firmware complexity and eliminating external energy storage components.

Availability

47C16-I/ST is available at Aetrix Electronics and suitable for industrial data loggers, motor control systems, and smart metering applications requiring stable component supply, long-lifecycle assurance, and AEC-Q100-qualified reliability.

Supply support for 47C16-I/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 leading provider of microcontrollers, analog, FPGA, and memory solutions, serving industrial, automotive, and communications markets with high-reliability silicon.

The 47C16-I/ST belongs to Microchip's EERAM product line, designed specifically to replace battery-backed SRAM in mission-critical systems where maintenance-free, long-term nonvolatile storage is essential.

FAQ

What is the function of the VCAP pin on the 47C16-I/ST?

The VCAP pin on the 47C16-I/ST connects to an external 5–6.8 µF capacitor that supplies hold-up energy during VCC collapse. When VCC drops below the trip voltage (4.0–4.4 V), the 47C16-I/ST uses charge from VCAP to complete an automatic SRAM-to-EEPROM store operation within 25 ms. Without VCAP, Auto-Store must be disabled and manual store via HS pin or software command is required.

How does the 47C16-I/ST handle write protection of its SRAM array?

The 47C16-I/ST implements software-controlled write protection via three nonvolatile BP2–BP0 bits in the STATUS register (address 0x00). These bits define protected address ranges-from upper 1/64 (7E0h–7FFh) to full array (000h–7FFh)-allowing selective locking of calibration tables or firmware parameters. Protection takes effect immediately after STATUS register write and persists across power cycles.

Can the 47C16-I/ST operate on a 1 MHz I²C bus reliably?

Yes, the 47C16-I/ST fully supports 1 MHz I²C operation per its AC specifications: minimum clock high/low times of 500 ns, rise/fall times ≤300 ns, and bus free time ≥500 ns. Its Schmitt-trigger inputs on SDA and SCL ensure noise immunity, and cascading support allows up to four 47C16-I/ST devices on a single 1 MHz bus without signal degradation.

What is the purpose of the HS pin on the 47C16-I/ST?

The HS (Hardware Store) pin on the 47C16-I/ST provides a dedicated, asynchronous method to initiate immediate SRAM-to-EEPROM store. A high pulse ≥150 ns triggers store regardless of VCAP status, VCC level, or ASE bit setting. This enables deterministic state capture-for example, saving operational parameters just before emergency shutdown-without relying on power-monitoring circuitry.

Is the 47C16-I/ST qualified for automotive applications?

The 47C16-I/ST is rated for Industrial temperature range (–40°C to +85°C) and is AEC-Q100 qualified, confirming its suitability for under-hood and chassis-mounted automotive electronics where extended thermal stability and reliability are required. It meets stress testing standards for temperature cycling, humidity, and ESD (>4 kV), making it appropriate for engine control modules and ADAS sensor nodes.