Renesas R1EX24008ASAS0I#U0

Overview

R1EX24008ASAS0I from Renesas Electronics is an 8 kbit (1024 × 8-bit) two-wire serial interface EEPROM using MONOS memory technology, operating from 1.8 V to 5.5 V supply, supporting 400 kHz I²C clock frequency, and rated for −40°C to +85°C industrial temperature range. It serves as nonvolatile configuration storage in microcontroller-based systems requiring reliable parameter retention across power cycles.

For engineers reviewing the R1EX24008ASAS0I datasheet, R1EX24008ASAS0I pinout, R1EX24008ASAS0I application, or R1EX24008ASAS0I equivalent, key selection considerations include its 16-byte page write capability, 5 ms write cycle time, 1,000k endurance at 25°C, 100-year data retention, and SOP-8 package with A0–A2 device address pins and hardware write-protect (WP) control.

Technical Context

This EEPROM implements a two-wire I²C-compatible serial interface with fixed 1010 device code, supporting byte and 16-byte page writes via SDA/SCL bidirectional communication. Its internal address counter enables current-address, random, and sequential read modes without external address latching.

The device integrates a voltage detector and high-voltage generator for MONOS cell programming, with internally pulled-down A0/A1/NP, A2, and WP pins-allowing flexible device addressing (up to 2 devices per bus) and hardware write protection that blocks all memory writes when WP = VIH.

Key Specifications

Pinout & Package

Package: 150-mil 8-pin plastic SOP (PRSP0008DF-B / FP-8DBV), lead-free and halogen-free (#U0).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C08D-SSHM-T and BR24G08NUX-10, the R1EX24008ASAS0I offers superior 1.8 V functionality, hardware WP pin for fail-safe write blocking, and guaranteed 100-year retention at 25°C-making it optimal for industrial and automotive applications demanding maximum data integrity assurance.

Availability

R1EX24008ASAS0I is available at Aetrix Electronics and suitable for industrial sensor calibration, smart meter firmware storage, and embedded controller boot configuration requiring stable component supply, long-lifecycle support, and RoHS-compliant sourcing.

Supply support for R1EX24008ASAS0I 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

Renesas Electronics is a Japanese semiconductor manufacturer specializing in microcontrollers, analog, and power devices for industrial, automotive, and infrastructure markets.

The R1EX24xxx series targets cost-sensitive, space-constrained embedded systems needing high-reliability nonvolatile storage with minimal external components-designed specifically for seamless integration into MCU-based designs with I²C interfaces.

FAQ

What is the maximum I²C clock frequency supported by the R1EX24008ASAS0I?

The R1EX24008ASAS0I supports a maximum I²C clock frequency of 400 kHz, as specified in its AC characteristics table. This rate is fully compatible with standard Fast-mode I²C controllers and ensures reliable data transfer while maintaining noise immunity. The device's tLOW (1200 ns) and tHIGH (600 ns) timing requirements must be met by the host controller to guarantee proper acknowledgment and data validity during reads and writes. R1EX24008ASAS0I does not support High-speed mode (3.4 MHz) or Ultra-fast mode.

Does the R1EX24008ASAS0I require external pull-up resistors on SDA and SCL lines?

Yes, the R1EX24008ASAS0I requires external pull-up resistors on both SDA and SCL lines because its SDA pin has an open-drain output structure and SCL is a passive input. The datasheet specifies that SDA transitions must occur only during SCL low periods and that VOL must remain ≤0.4 V at 3.0 mA sink current. Typical values range from 2.2 kΩ to 10 kΩ depending on bus capacitance and VCC; lower resistance improves rise time but increases power consumption. R1EX24008ASAS0I's 6.0 pF pin capacitance helps maintain signal integrity even with moderate bus loads.

How does the write-protect (WP) pin function on the R1EX24008ASAS0I?

The WP pin on the R1EX24008ASAS0I is an active-high hardware write protection input. When WP is driven to VIH (≥0.7 × VCC), all write operations-including byte and page writes-are blocked, and the device responds with a NO ACK ('1') after receiving write data. When WP is at VIL (≤0.3 × VCC) or left unconnected (internally pulled down to VSS), full read/write access is enabled. This feature prevents unintended writes during power-up/down transients or software crashes. R1EX24008ASAS0I's internal pull-down ensures safe default behavior without external biasing.

What is the endurance rating of the R1EX24008ASAS0I at elevated temperatures?

The R1EX24008ASAS0I is rated for 1,000,000 write/erase cycles at 25°C and 100,000 cycles at 85°C, as documented in the Memory Cell Characteristics table. This derating reflects accelerated oxide wear at higher junction temperatures. The device's MONOS technology provides better high-temperature endurance than conventional floating-gate EEPROMs. For applications operating continuously at 85°C, design margins should account for this reduced cycle count-e.g., limiting daily writes to ~30 cycles ensures >9-year lifetime. R1EX24008ASAS0I's endurance is not 100% tested but statistically validated per JEDEC standards.

Can the R1EX24008ASAS0I operate from a 1.8 V supply while maintaining full I²C functionality?

Yes, the R1EX24008ASAS0I is fully specified to operate from 1.8 V to 5.5 V, including complete I²C functionality at 1.8 V. Its DC characteristics confirm VIH = 1.26 V (0.7 × 1.8 V) and VIL = 0.54 V (0.3 × 1.8 V), and AC timing (tAA = 900 ns max, tLOW = 1200 ns) remains valid across the entire voltage range. The MONOS memory cell enables stable 1.8 V programming without charge-pump overhead. R1EX24008ASAS0I's 1.0 mA max active read current and 3.0 mA max write current at 1.8 V ensure compatibility with ultra-low-power microcontrollers and energy-harvesting systems.