Microchip Technology 47C16-E/ST

Overview

47C16-E/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. Used in automotive instrumentation and industrial controllers where persistent memory state must survive uncontrolled power cycles.

For engineers reviewing the 47C16-E/ST datasheet, 47C16-E/ST pinout, 47C16-E/ST application, or 47C16-E/ST equivalent, key selection criteria include its 25 ms max store time, hardware store pin (HS), software-controlled recall, 1 million EEPROM store cycles, and AEC-Q100 qualification for extended temperature operation (–40°C to +125°C).

Technical Context

The 47C16-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 (via VCAP monitoring), manually via HS pin pulse, or through software commands written to the COMMAND register (0x55).

I²C interface compliance includes 100 kHz / 400 kHz / 1 MHz modes, Schmitt-triggered SDA/SCL inputs for noise immunity, and cascading support for up to four devices on one bus. The STATUS register (0x00) provides nonvolatile control of auto-store enable (ASE), block write protection (BP2–BP0), and event detection (EVENT) on the HS pin.

Key Specifications

Pinout & Package

47C16-E/ST is housed in an 8-lead TSSOP package (ST suffix), with lead pitch 0.65 mm and body dimensions 4.4 mm × 3.0 mm. Pin 1 is marked by a dot or bevelled corner; pin numbering follows standard counter-clockwise convention.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 47C16-E/ST, the 47L16-E/ST offers identical functionality at 3.3 V with lower trip voltage, while the FM24CL16B-G replaces EEPROM backup with F-RAM for infinite endurance-but sacrifices automotive qualification, hardware store, and 5 V compatibility.

Availability

47C16-E/ST is available at Aetrix Electronics and suitable for automotive instrumentation, industrial data loggers, and medical calibration storage requiring stable component supply across extended temperature and long product lifecycles.

Supply support for 47C16-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 global semiconductor company specializing in microcontrollers, analog, FPGA, and memory solutions, with emphasis on reliability, longevity, and automotive-grade qualification.

The 47C16-E/ST belongs to Microchip's EERAM family-designed specifically to replace battery-backed SRAM and discrete EEPROM+SRAM combinations in mission-critical, power-interrupted environments.

FAQ

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

The VCAP pin on the 47C16-E/ST connects to an external 5–6.8 µF capacitor that enables automatic store functionality. When VCC drops below the trip voltage (4.0–4.4 V), the stored charge on VCAP sustains internal circuitry long enough to transfer SRAM contents to EEPROM. If VCAP is unconnected, Auto-Store must be disabled (ASE = 0) and VCAP tied to VCC to prevent EEPROM corruption during power loss. This behavior is explicitly defined in DS20005371E Section 1.1 and Table 1-1.

How does the Hardware Store (HS) pin operate on the 47C16-E/ST?

The HS pin on the 47C16-E/ST initiates an immediate SRAM-to-EEPROM store upon detection of a low-going pulse ≥150 ns wide (per AC Characteristic THSPW). Unlike Auto-Store, it functions independently of VCAP, ASE bit setting, or AM flag status-and takes priority over ongoing I²C transactions, aborting them to execute the store. The HS pin is ignored during active Store/Recall operations or when VCAP is below VTRIP, as confirmed in DS20005371E Sections 2.4.1 and Figure 1-3.

Can the 47C16-E/ST be used in a 3.3 V system?

No-the 47C16-E/ST is specified only for 4.5–5.5 V operation (47CXX series), and its VTRIP (4.0–4.4 V) and DC characteristics assume 5 V rail compliance. Attempting to power it from 3.3 V will result in failure to meet timing, store/recall, or I²C electrical specifications. For 3.3 V designs, the pin-compatible 47L16-E/ST (2.7–3.6 V, VTRIP = 2.4–2.6 V) is the qualified alternative, as documented in the Device Selection Table on DS20005371E page 2.

What is the maximum number of devices that can share one I²C bus with the 47C16-E/ST?

Up to four 47C16-E/ST devices can be cascaded on a single I²C bus using unique combinations of A1 and A2 pins, which set the two least-significant address bits of the 7-bit client address (1010 A2 A1 0 R/W). With A1/A2 hardwired to VCC, VSS, or left floating (with internal pull-downs per DS20005371E Section 2.2), four distinct addresses are supported. This cascading capability is explicitly stated in the "Features" section on DS20005371E page 1 and verified in Table 2-3.

Does the 47C16-E/ST require external pull-up resistors on SDA and SCL lines?

Yes-the 47C16-E/ST features open-drain SDA and SCL pins and requires external pull-up resistors to VCC on both lines to establish valid logic high levels. Pull-up values depend on bus capacitance and target speed: for 1 MHz operation, typical values range from 1.8 kΩ to 4.7 kΩ (per I²C specification and DS20005371E Figure 1-1). Schmitt-trigger inputs tolerate slow rise times, but pull-ups remain mandatory for bus functionality, as shown in all application schematics (DS20005371E pages 2–3).