Renesas X5323S8I

Overview

X5323S8I 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 (≥100ms), monitors VCC against a factory-set 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 brown-out protection and nonvolatile configuration storage.

For engineers reviewing the X5323S8I datasheet, X5323S8I pinout, X5323S8I application, or X5323S8I equivalent, this page delivers verified technical context, exact pin functions for CS/WDI, SO, SCK, SI, WP, VSS, VCC, and RESET/RESET, confirmed 4.5V VTRIP threshold with ±125mV tolerance, 2MHz SPI interface compliance, and real-world alternatives with documented functional trade-offs.

Technical Context

The X5323S8I implements a dual-function CS/WDI pin that serves as chip select for SPI communication and watchdog input for reset initiation on timeout. Its internal low-VCC detection circuit asserts RESET/RESET when VCC drops below 4.5V and holds it active for ≥200ms after VCC recovers above threshold.

It embeds a 32kbit (4k × 8) SPI EEPROM with Block Lock™ protection, supporting 32-byte page writes and self-timed 10ms write cycles. The device uses volatile flag bits to distinguish watchdog-induced resets from voltage-supervision resets, and allows in-circuit reprogramming of the VTRIP threshold via dedicated VP-based sequences.

Key Specifications

Pinout & Package

Package: 8-lead SOIC (Small Outline Integrated Circuit), RoHS-compliant, Pb-free, body width 3.9mm, pitch 1.27mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with X5323S8I, MAX6361KA29+T offers lower supply voltage flexibility but lacks field-reprogrammable VTRIP and half the EEPROM capacity, while STM8S105K4T6C replaces discrete supervision with software-managed reset - making X5323S8I optimal for designs prioritizing hardware determinism, field calibration, and high-density configuration storage.

Availability

X5323S8I 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 across extended temperature ranges and long production lifecycles.

Supply support for X5323S8I 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 manufacturer specializing in precision analog, power management, and interface ICs for industrial, aerospace, and communications markets.

The X5323 product line was designed to consolidate reset supervision, watchdog safety, and nonvolatile memory into a single package - targeting cost-sensitive, space-constrained embedded systems needing guaranteed boot integrity and field-configurable voltage thresholds.

FAQ

What is the factory-default VTRIP voltage setting for the X5323S8I?

The X5323S8I ships with a factory-programmed VTRIP of 4.5V to 4.75V, specifically configured for the "-4.5A" variant per the FN8131 datasheet ordering table. This threshold is laser-trimmed and remains stable over temperature and time unless reprogrammed using the VP-based VTRIP adjustment sequence defined on page 4 of the datasheet. The X5323S8I does not ship with the generic 4.25–4.5V or 2.7V variants - its identity is tied exclusively to the 4.5A specification.

Does the X5323S8I support both active-low and active-high reset outputs?

No, the X5323S8I provides only an active-low RESET/RESET output. The datasheet explicitly identifies X5323 as the RESET (active low) variant and distinguishes it from the X5325 family, which offers active-high reset. Pin 8 is labeled RESET/RESET with slash notation indicating active-low polarity, and all timing diagrams (e.g., page 12) show assertion as a logic-low signal. There is no internal configuration or external pin to invert this behavior on the X5323S8I.

Can the watchdog timer on the X5323S8I be disabled after power-up?

Yes, the watchdog timer on the X5323S8I can be disabled after power-up by programming the WD0 and WD1 bits in the status register to "11" using the WRSR instruction. The datasheet states on page 7 that the watchdog is shipped disabled (WD1=1, WD0=1), and these bits are nonvolatile - meaning the setting persists across power cycles. Disabling the watchdog removes its reset contribution, leaving only power-on and low-VCC reset functionality active.

What is the maximum write endurance and data retention for the EEPROM in the X5323S8I?

The EEPROM in the X5323S8I is rated for a minimum of 100,000 write/erase cycles and guarantees a minimum data retention of 100 years, as specified on page 6 of the FN8131 datasheet under "SPI Serial Memory." These values are measured under standard operating conditions (–40°C to +85°C) and apply to the entire 32kbit array. Endurance is unaffected by Block Lock™ protection status, and retention holds regardless of VTRIP programming activity.

Is the X5323S8I pin-compatible with other members of the X5323/X5325 family?

Yes, the X5323S8I is pin-compatible with all 8-lead SOIC variants in the X5323/X5325 family, including X5323S8Z, X5323S8IZ, X5325S8Z, and X5325S8IZ. All share identical 8-pin SOIC footprint, pin numbering, and pin functions (CS/WDI, SO, WP, VSS, VCC, SCK, SI, RESET/RESET). Differences lie solely in VTRIP voltage, temperature grade, and reset polarity - not physical layout or electrical pin behavior.