Renesas X5083S8I

Overview

X5083S8I from Intersil is a CPU supervisor IC integrating power-on reset control, selectable watchdog timer, low-voltage supply supervision, and 8Kbit SPI EEPROM with Block Lock™ protection. It operates across 2.7V–5.5V VCC, features factory-default 4.63V reset threshold (±2.5%), and supports industrial temperature range (−40°C to +85°C). Used in network servers and industrial process controllers for reliable boot sequencing and data retention.

For engineers reviewing the X5083S8I datasheet, X5083S8I pinout, X5083S8I application, or X5083S8I equivalent, key selection criteria include programmable VTRIP voltage, watchdog timeout options (200ms/600ms/1.4s/disabled), SPI interface compliance (3.3MHz, modes 0,0 & 1,1), and block-lock EEPROM configuration for critical parameter storage.

Technical Context

The X5083S8I implements independent analog voltage monitoring with internal comparator and hysteresis to assert RESET when VCC drops below the programmed trip point (e.g., 4.63V ±2.5%). Its watchdog circuit uses nonvolatile WD0/WD1 bits to select timeout intervals without requiring reconfiguration after power cycles.

EEPROM functionality employs Intersil's Direct Write™ cell architecture, enabling 100,000 write cycles and 100-year data retention. The SPI interface supports page-write mode (16-byte pages) with 5ms typical write cycle time and built-in write enable latch plus WP pin for dual-layer write protection.

Key Specifications

Pinout & Package

Package: 8-lead SOIC (RoHS-compliant, M8.15E package drawing).

Key Features

Applications

Equivalent & Alternatives

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

Compared with X5083S8I, MAX6361KA29+T offers lower cost but sacrifices VTRIP adjustability and memory size, while STM809SWX6F eliminates integrated memory and watchdog-increasing BOM count and firmware complexity for equivalent functionality.

Availability

X5083S8I is available at Aetrix Electronics and suitable for industrial process control, network server BIOS storage, and battery-powered environmental sensing requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for X5083S8I 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 Corporation is a leader in precision analog and power management ICs, serving industrial, infrastructure, and high-end consumer markets with robust, high-reliability solutions.

The X5083 series was designed to consolidate reset, watchdog, voltage monitoring, and EEPROM into a single chip for space-constrained embedded systems-reducing board area and improving system-level reliability in communications and computing equipment.

FAQ

What is the factory-default VTRIP voltage for X5083S8I?

The X5083S8I ships with a factory-programmed VTRIP threshold of 4.63V ±2.5%, corresponding to the "-4.5A" suffix in its ordering code. This value remains stable over temperature and time unless reprogrammed using the VP=15–18V sequence described in the datasheet. Reprogramming is supported across the full 2.0–5.0V range and retains settings through power cycles.

Does X5083S8I support SPI mode 0,1 or 1,0?

No, X5083S8I supports only SPI modes 0,0 (CPOL=0, CPHA=0) and 1,1 (CPOL=1, CPHA=1), as explicitly stated in the Features section of the FN8127 datasheet. Attempting mode 0,1 or 1,0 will result in incorrect data sampling due to mismatched clock polarity and phase timing relative to SI/SO edges.

How does the watchdog timer behave after power cycling X5083S8I?

The watchdog timer settings in X5083S8I are stored in nonvolatile status register bits WD1 and WD0, so they persist across power cycles. If configured for 600ms timeout before power-down, it resumes that same interval upon next power-up-no reinitialization is required. The timer only starts counting after CS/WDI receives its first HIGH-to-LOW transition post-reset.

Can X5083S8I's EEPROM be written while VCC is below VTRIP?

No. When VCC falls below the programmed VTRIP threshold, the X5083S8I inhibits all SPI communication-including write operations-and drives RESET active. The datasheet states: "While VCC < VTRIP communications to the device are inhibited." This prevents corrupted writes during brownout conditions, ensuring EEPROM integrity.

What is the maximum clock frequency supported by X5083S8I's SPI interface?

X5083S8I supports a maximum SPI clock frequency of 3.3MHz under recommended operating conditions (2.7V–5.5V VCC), as specified in the AC Electrical Specifications table on page 14 of FN8127 Rev 4.00. Exceeding this limit risks setup/hold timing violations and unreliable data transfer, especially at lower VCC levels.