Renesas X5045S8IZT1

Overview

X5045S8IZT1 from Intersil (now Renesas) is a CPU supervisor IC integrating power-on reset control, watchdog timer, supply voltage supervision, and 4Kbit SPI EEPROM in a single 8-lead SOIC package. It provides active-low RESET output, supports 2.7–5.5V VCC, features four factory-programmable VTRIP thresholds (e.g., 2.63V, 2.93V), and delivers 1M write-cycle EEPROM endurance with block lock protection - used in industrial process controllers for brownout recovery and firmware parameter storage.

For engineers reviewing the X5045S8IZT1 datasheet, X5045S8IZT1 pinout, X5045S8IZT1 application, or X5045S8IZT1 equivalent, key selection criteria include its programmable reset threshold, watchdog timeout configurability (200ms/600ms/1.4s), SPI interface timing compliance (3.3MHz max), and dual-level hardware/software write protection for critical configuration data.

Technical Context

The X5045S8IZT1 implements a dual-function CS/WDI pin to monitor microcontroller activity and trigger watchdog reset if un-toggled beyond selected timeout. Its low-voltage detection circuit asserts RESET until VCC exceeds VTRIP for 200ms, with valid operation down to 1V VCC.

EEPROM memory is organized as 512 × 8 bits with page-write capability (16-byte pages), Direct Write™ cell technology, and nonvolatile status register controlling both watchdog timing and block lock protection (1/4, 1/2, full, or no array protection).

Key Specifications

Pinout & Package

Package: 8-lead SOIC (Pb-free, RoHS-compliant), -40°C to +85°C industrial temperature range.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6361KA29+T and MCP9800T-E/MS, the X5045S8IZT1 uniquely integrates programmable reset, multi-interval watchdog, and high-endurance SPI EEPROM - enabling single-chip system resilience where voltage margin tuning, fault recovery timing, and secure configuration storage are co-dependent design requirements.

Availability

X5045S8IZT1 is available at Aetrix Electronics and suitable for industrial process control, network infrastructure, medical diagnostics, and battery-powered data logging requiring stable component supply and long-term lifecycle support.

Supply support for X5045S8IZT1 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 (acquired by Renesas Electronics in 2017) is a semiconductor company specializing in high-performance analog and mixed-signal ICs for power management, precision analog, and interface applications.

The X5045S8IZT1 belongs to Intersil's CPU Supervisor family, designed specifically to consolidate power monitoring, fault recovery, and nonvolatile configuration storage into one space- and cost-optimized device for resource-constrained embedded systems.

FAQ

What is the factory-default VTRIP voltage for X5045S8IZT1?

The X5045S8IZT1 is shipped with a factory-default VTRIP of 2.63V ±2.5%, corresponding to the "-2.7" suffix variant. This threshold is reprogrammable using a 15–18V programming voltage applied to the WP pin and specific SPI command sequences documented in the FN8126 datasheet. The X5045S8IZT1 retains its programmed VTRIP value across power cycles and temperature variations.

Does X5045S8IZT1 support active-high RESET output?

No, the X5045S8IZT1 provides only an active-low open-drain RESET output. It does not offer an active-high variant in the same package or marking. For active-high reset functionality, designers must use an external inverter or select the pin-compatible X5043 series (e.g., X5043S8IZT1), which features active-high RESET/RESET output alongside identical supervision and EEPROM capabilities.

How many watchdog timeout intervals does X5045S8IZT1 support, and how are they selected?

The X5045S8IZT1 supports three selectable watchdog timeout intervals: 200ms, 600ms, and 1.4 seconds. These are configured via nonvolatile WD0 and WD1 bits in the status register, written using the WRSR instruction. The factory default is watchdog disabled (WD0=WD1=1). Selection is persistent across power cycles and requires no external components - enabling deterministic fault recovery timing without firmware intervention.

What is the maximum clock frequency supported by X5045S8IZT1's SPI interface?

The X5045S8IZT1 supports a maximum SPI clock frequency of 3.3MHz under recommended operating conditions (VCC = 2.7–5.5V). This timing is validated across the full industrial temperature range (-40°C to +85°C) and allows efficient read/write operations without requiring clock stretching or wait states. The X5045S8IZT1 meets standard SPI phase/polarity modes (CPOL=0, CPHA=0) and is interoperable with common microcontroller SPI peripherals.

Can X5045S8IZT1's EEPROM be partially protected, and how is this enforced?

Yes, X5045S8IZT1's 4Kbit EEPROM supports partial protection via Block Lock™ - controlled by nonvolatile BL0/BL1 bits in the status register. These bits enable write-protection of 0%, 25% (upper quarter), 50% (upper half), or 100% (entire array), while allowing unrestricted reads. Protection is enforced simultaneously by hardware (WP pin) and software (WREN latch + status register), ensuring that X5045S8IZT1 prevents unintended writes even during power transients or firmware crashes.