Renesas X5323S8

Overview

X5323S8 from Intersil is a CPU supervisor IC integrating power-on reset control, watchdog timer, supply voltage supervision, and 32kbit SPI EEPROM in a single 8-lead SOIC package. It asserts active-low RESET during power-up (≥200ms), monitors VCC against a factory-programmed 4.5V trip point (4.5–4.75V range), supports selectable watchdog timeout (200/600/1400ms), and operates from 4.5V to 5.5V - used in industrial microcontroller systems requiring reliable boot sequencing and nonvolatile configuration storage.

For engineers reviewing the X5323S8 datasheet, X5323S8 pinout, X5323S8 application, or X5323S8 equivalent, this page delivers verified functional identity, validated SOIC-8 pin mapping, confirmed 4.5V reset threshold and watchdog timing options, real-world EEPROM block-lock protection behavior, and two technically documented alternative parts for design continuity.

Technical Context

The X5323S8 implements a dual-function CS/WDI pin that serves as both chip select and watchdog input: a HIGH-to-LOW transition resets the watchdog timer, while sustained HIGH or LOW beyond the selected timeout triggers RESET assertion. Its low-voltage detection circuit holds RESET active until VCC exceeds the 4.5V threshold for 200ms and remains valid down to 1V.

Internally, it combines a serial EEPROM array organized as 4k × 8 bits with Intersil's Block Lock™ protection, supporting 32-byte page writes and self-timed 10ms write cycles. The status register includes volatile WIP/WEL flags and nonvolatile WD0/WD1 (watchdog timeout selection) and BL0/BL1 (block lock level) bits, all programmable via SPI WRSR instruction.

Key Specifications

Pinout & Package

Package: 8-lead SOIC (Pb-free, RoHS compliant), 3.9mm × 4.9mm body, 1.27mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with X5323S8, MAX6361KA29+T offers lower cost but sacrifices VTRIP adjustability and half the EEPROM capacity, while STM6805RWY6F provides tighter reset tolerance but forces external memory and removes watchdog functionality - making X5323S8 the sole option combining all four functions in one SOIC-8 package.

Availability

X5323S8 is available at Aetrix Electronics and suitable for industrial PLC controllers, medical diagnostic devices, smart energy meters, and automotive body control modules requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for X5323S8 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) designs high-performance analog and mixed-signal ICs for industrial, computing, and communications markets, emphasizing reliability, integration, and long-term product support.

The X5323 family was developed to consolidate power management, system supervision, and nonvolatile storage into a single chip - targeting cost-sensitive, space-constrained embedded systems needing guaranteed boot integrity and field-updatable configuration.

FAQ

What is the factory-default reset threshold voltage for X5323S8?

The X5323S8 ships with a factory-programmed V_TRIP of 4.5V to 4.75V, specifically designated for the "-4.5A" variant per the FN8131 datasheet ordering table. This threshold is laser-trimmed during production and remains stable across temperature and time unless reprogrammed using the VP-based VTRIP adjustment sequence.

Does X5323S8 support both active-high and active-low reset outputs?

No - X5323S8 provides only an active-low open-drain RESET/RESET output. The X5325 variant is the active-high counterpart. The X5323S8 datasheet explicitly identifies its output as RESET (active low), and the pin description confirms it asserts LOW during power-up, brown-out, or watchdog timeout.

Can the watchdog timer on X5323S8 be disabled after power-up?

Yes - the watchdog timer is shipped disabled (WD1 = 1, WD0 = 1) and can remain disabled indefinitely. To enable it, the host microcontroller must issue a WRSR instruction to set WD0 and/or WD1 to non-11 states. Once enabled, the watchdog remains active across power cycles unless explicitly reconfigured.

What EEPROM protection levels does X5323S8 support via Block Lock™?

X5323S8 supports four nonvolatile block lock configurations via BL0/BL1 bits: none (factory default), top quarter ($0C00–$0FFF), top half ($0800–$0FFF), or full array ($0000–$0FFF). Protection is enforced at the hardware level - write attempts to locked regions are ignored, and reads remain fully accessible.

Is X5323S8 pin-compatible with earlier X25323 devices?

Yes - the X5323S8 is a direct replacement for the obsolete X25323PZ-4.5A and X25323S8Z-4.5A, sharing identical 8-lead SOIC pinout, electrical specifications, and functional behavior. The datasheet states "X5323, X5325 (Replaces X25323, X25325)" and lists X5323S8Z-4.5A as the recommended replacement for discontinued X25323 variants.