Renesas X5325S8I-2.7T1

Overview

X5325S8I-2.7T1 from Intersil is a CPU supervisor IC with integrated 32kbit SPI EEPROM, combining power-on reset control, watchdog timer, supply voltage supervision, and block-lock protected memory in a single 8-lead SOIC package. It operates from 2.7V to 5.5V, features factory-default 2.55V–2.7V VTRIP threshold, supports -40°C to +85°C industrial temperature range, and delivers active-low RESET output with 200ms timeout - used in microcontroller-based embedded systems requiring reliable power sequencing and nonvolatile configuration storage.

For engineers reviewing the X5325S8I-2.7T1 datasheet, X5325S8I-2.7T1 pinout, X5325S8I-2.7T1 application, or X5325S8I-2.7T1 equivalent, this device serves as a system-level supervisory solution where deterministic reset timing, programmable voltage thresholds, watchdog timeout selection (200ms/600ms/1.4s), EEPROM data retention (>100 years), and SPI interface compatibility with standard microcontrollers are critical selection criteria.

Technical Context

The X5325S8I-2.7T1 integrates a dedicated low-voltage detection circuit with reprogrammable VTRIP threshold (2.55V–2.7V nominal), a nonvolatile watchdog timer controlled by WD0/WD1 bits, and a 32kbit (4k × 8) SPI EEPROM with Block Lock™ protection. Its RESET/RESET output asserts at VCC ≈ 1V during power-up and remains active until VCC exceeds VTRIP for 200ms.

It implements a 2MHz SPI interface (modes 0,0 and 1,1), supports page-write (32-byte) and self-timed write cycles (10ms typical), and includes volatile flag bit to distinguish watchdog vs. brown-out reset causes. The CS/WDI pin serves dual function: chip select input and watchdog trigger via HIGH-to-LOW transition.

Key Specifications

Pinout & Package

Package: 8-lead SOIC (Small Outline Integrated Circuit), RoHS-compliant, Pb-free matte tin termination, compatible with reflow soldering per IPC/JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6361KA29+T and STM6803RWDY6F, the X5325S8I-2.7T1 uniquely combines field-programmable VTRIP, 32kbit EEPROM with block lock, and industrial temperature support - making it optimal for systems requiring both supervisory reliability and secure, long-term configuration storage without external components.

Availability

X5325S8I-2.7T1 is available at Aetrix Electronics and suitable for industrial PLC controllers, medical diagnostic devices, smart energy meters, and automotive telematics units requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for X5325S8I-2.7T1 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

Intersil (now part of Renesas Electronics) is a semiconductor company specializing in precision analog, power management, and interface ICs for industrial, computing, and communications markets.

The X5325 family was designed to consolidate power supervision, watchdog safety, and nonvolatile storage into one IC for microcontroller-based systems - reducing board area, BOM count, and system-level validation effort in embedded applications.

FAQ

What is the reset output polarity of the X5325S8I-2.7T1?

The X5325S8I-2.7T1 features an active-high RESET output (denoted by "RESET" in the part number suffix), unlike the X5323 series which provides active-low RESET/RESET. This open-drain output requires an external pull-up resistor and asserts high during power-up, brown-out, or watchdog timeout conditions. The X5325S8I-2.7T1 maintains this behavior across its full operating temperature range and VCC supply span.

How is the VTRIP threshold programmed on the X5325S8I-2.7T1?

The VTRIP threshold on the X5325S8I-2.7T1 is programmed using a dedicated VP (programming voltage) sequence applied to SCK and SI pins while holding CS/WDI and WP HIGH. A 15–18V pulse sets the new threshold; applying VP to SI only resets it to native level. The procedure requires precise timing (tVPS ≥1µs, tTHD ≥10ms) and is performed in-system without removing the device from the PCB. The X5325S8I-2.7T1 retains the programmed value indefinitely.

Does the X5325S8I-2.7T1 support SPI mode 0,1 or 1,0?

No, the X5325S8I-2.7T1 supports only SPI modes 0,0 (CPOL=0, CPHA=0) and 1,1 (CPOL=1, CPHA=1). It does not support modes 0,1 or 1,0. This limitation is defined in the datasheet's AC Electrical Specifications and verified in the Serial Peripheral Interface section. Users must configure their microcontroller's SPI peripheral accordingly to ensure correct clock polarity and phase alignment during opcode, address, and data transfers with the X5325S8I-2.7T1.

What is the maximum write endurance and data retention of the EEPROM in the X5325S8I-2.7T1?

The EEPROM in the X5325S8I-2.7T1 guarantees minimum 100,000 write/erase cycles and minimum 100 years of data retention at +25°C, based on Intersil's Direct Write™ cell technology. These specifications are validated across the full industrial temperature range (-40°C to +85°C) and apply to all 32kbit of memory. The X5325S8I-2.7T1 achieves this through proprietary cell architecture and on-chip write-cycle control, eliminating need for external wear-leveling firmware.

Can the watchdog timer on the X5325S8I-2.7T1 be disabled after power-up?

Yes, the watchdog timer on the X5325S8I-2.7T1 can be disabled after power-up by writing WD1=1 and WD0=1 to the status register using the WRSR instruction. This setting persists across power cycles because the bits are nonvolatile. Once disabled, the watchdog remains inactive until explicitly re-enabled via WRSR, even if CS/WDI toggling continues. The X5325S8I-2.7T1 ships from factory with watchdog disabled by default.