Renesas R1EX24002ASAS0I#U0

Overview

R1EX24002ASAS0I from Renesas Electronics is a 2 kbit (256 × 8-bit) two-wire serial interface EEPROM with I²C bus compatibility, 1.8–5.5 V single-supply operation, and 400 kHz clock frequency. It delivers 5 ms write cycle time, 1,000k endurance cycles at 25°C, and 100-year data retention - deployed in industrial control modules for nonvolatile parameter storage.

For engineers reviewing the R1EX24002ASAS0I datasheet, R1EX24002ASAS0I pinout, R1EX24002ASAS0I application, or R1EX24002ASAS0I equivalent, key selection considerations include its SOP-8 package, WP-enabled hardware write protection, 16-byte page programming capability, and guaranteed operation across −40 to +85°C.

Technical Context

This device implements a two-wire I²C-compatible serial interface with fixed 1010 device code and user-configurable A0–A2 address pins enabling up to eight devices on one bus. Its internal MONOS memory technology enables high reliability with low-voltage operation and integrated voltage detector.

The R1EX24002ASAS0I supports byte and page write modes (up to 16 bytes per cycle), current/random/sequential read operations, and acknowledge polling to monitor write completion. Write protection is controlled via the dedicated WP pin, which disables all writes when driven high.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C02D-SSHM-T, the R1EX24002ASAS0I offers stricter noise immunity (50 ns suppression) and integrated voltage detector for robust power sequencing - advantageous in electrically noisy PLC cabinets. Against M95020-WMN6TP, it provides native I²C compatibility and hardware WP, reducing firmware complexity for secure parameter locking.

Availability

R1EX24002ASAS0I is available at Aetrix Electronics and suitable for industrial sensor calibration, smart meter configuration storage, and PLC I/O module settings requiring stable component supply across extended product lifecycles.

Supply support for R1EX24002ASAS0I 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 was designed specifically for reliable, low-power nonvolatile storage in industrial automation and metering applications where long-term data integrity and noise resilience are mandatory.

FAQ

What is the maximum I²C clock frequency supported by the R1EX24002ASAS0I?

The R1EX24002ASAS0I supports a maximum I²C clock frequency of 400 kHz, as specified in its AC characteristics table. This value is guaranteed across the full operating temperature range (−40°C to +85°C) and supply voltage range (1.8 V to 5.5 V). Exceeding this frequency may result in timing violations, failed acknowledgments, or corrupted writes. The R1EX24002ASAS0I does not support standard-mode-plus (1 MHz) or fast-mode-plus (3.4 MHz) I²C speeds.

Does the R1EX24002ASAS0I require external pull-up resistors on SDA and SCL lines?

Yes, the R1EX24002ASAS0I requires external pull-up resistors on both SDA and SCL lines because these pins use open-drain output structures. The datasheet specifies that SDA must be pulled up to ensure proper signal levels and timing compliance. Resistor values must be selected based on bus capacitance, desired rise time (≤300 ns), and VOL/IOL specifications - typically 2.2 kΩ to 10 kΩ for standard 400 kHz operation. Failure to install pull-ups will prevent I²C communication.

How does the WP pin function on the R1EX24002ASAS0I, and what happens when it is left unconnected?

When the WP pin on the R1EX24002ASAS0I is driven high (VIH ≥ 0.7 × VCC), all write operations are disabled - the device responds with a NO ACK after receiving the device address and memory address. When WP is low (VIL ≤ 0.3 × VCC), full read/write access is enabled. The WP pin is internally pulled down to VSS, so leaving it unconnected results in normal write functionality. However, Renesas recommends hard-wiring WP to VSS or VCC to prevent noise-induced glitches.

What is the guaranteed data retention period for the R1EX24002ASAS0I at 85°C ambient temperature?

At 85°C ambient temperature, the R1EX24002ASAS0I guarantees a minimum data retention period of 10 years, as stated in the Memory Cell Characteristics table. This is distinct from its 100-year retention rating at 25°C. The reduction reflects accelerated charge loss mechanisms at elevated temperatures. For applications operating continuously at 85°C, this 10-year specification ensures reliable long-term storage of calibration data, configuration flags, or usage logs without periodic refresh.

Can the R1EX24002ASAS0I be used in a system powered by 1.8 V, and what performance trade-offs apply?

Yes, the R1EX24002ASAS0I is fully specified for 1.8 V operation, with DC and AC parameters validated down to this voltage. At 1.8 V, VOL1 is guaranteed ≤0.2 V (with IOL = 1.5 mA), and write current ICC2 drops to ≤1.0 mA (typical). However, the maximum clock frequency remains 400 kHz, and tLOW/tHIGH timing requirements tighten slightly due to slower transistor switching. System designers must verify SDA/SCL rise times meet ≤300 ns with appropriate pull-up values at 1.8 V.