Renesas X5043S8IZT2

Overview

X5043S8IZT2 from Intersil (now Renesas) is a CPU supervisor IC integrating power-on reset, watchdog timer, supply voltage supervision, and 4Kbit SPI EEPROM in a single 8-lead SOIC package. It provides active-low RESET output, selectable watchdog timeout (200 ms/600 ms/1.4 s), four factory VTRIP thresholds (including 2.63 V ±2.5%), and block-lock protected EEPROM with 1M write endurance - deployed in industrial process controllers for brownout recovery and firmware parameter retention.

For engineers reviewing the X5043S8IZT2 datasheet, X5043S8IZT2 pinout, X5043S8IZT2 application, or X5043S8IZT2 equivalent, key selection criteria include its -40°C to +85°C industrial temperature range, reprogrammable VTRIP threshold via VP=15–18 V sequence, SPI clock rate up to 3.3 MHz, and dual protection modes (WP pin + status-register block lock) for critical configuration storage.

Technical Context

The X5043S8IZT2 implements a dedicated low-voltage detection circuit with hysteresis that asserts RESET/RESET until VCC exceeds the selected VTRIP (2.63 V) by ≥200 ms. Its watchdog timer monitors CS/WDI transitions and triggers reset if no high-to-low edge occurs within the user-configured timeout interval stored in nonvolatile status register bits WD1/WD0.

EEPROM operation uses standard SPI protocol with MSB-first 8-bit opcodes (READ, WRITE, WREN, RDSR, WRSR), supports 16-byte page writes with 5 ms typical write cycle time, and enforces write protection through three independent mechanisms: Write Enable Latch (WEL), WP pin logic level, and BL0/BL1 block lock bits defining protected memory regions ($000–$1FF, $100–$1FF, $180–$1FF, or none).

Key Specifications

Pinout & Package

Package: 8-lead SOIC (Pb-free, RoHS compliant), body width 3.9 mm, thermal pad not present.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6361KA26+T, X5043S8IZT2 delivers 10× higher EEPROM endurance and field-programmable VTRIP, enabling long-life industrial deployments; versus MCP9808-E/SN, it provides complete power supervision functionality absent in temperature sensors.

Availability

X5043S8IZT2 is available at Aetrix Electronics and suitable for industrial process controllers, network infrastructure equipment, and medical infusion pumps requiring stable component supply across extended product lifecycles.

Supply support for X5043S8IZT2 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

Renesas Electronics Corporation (formerly Intersil) is a global semiconductor leader specializing in microcontrollers, analog, power management, and timing solutions for industrial, automotive, and infrastructure markets.

The X5043S8IZT2 belongs to Renesas' legacy CPU supervisor family designed specifically for embedded systems needing combined power monitoring, fail-safe reset, and robust nonvolatile configuration storage in space-constrained applications.

FAQ

What is the factory-set VTRIP voltage for X5043S8IZT2?

The X5043S8IZT2 ships with a factory-programmed VTRIP threshold of 2.63 V ±2.5%, corresponding to the "-2.7" suffix in the ordering nomenclature. This value is verified during production test and remains stable over temperature and time unless reprogrammed using the VP=15–18 V sequence described in the FN8126 datasheet.

Does X5043S8IZT2 support both active-low and active-high reset outputs?

No, X5043S8IZT2 provides only an active-low open-drain RESET output. The "X5045" variant in the same family offers active-high RESET, but X5043S8IZT2 is strictly active-low. Its RESET/RESET pin requires an external pull-up resistor to VCC for proper logic-level translation.

How is the watchdog timeout period configured on X5043S8IZT2?

The watchdog timeout on X5043S8IZT2 is set via two nonvolatile bits (WD1 and WD0) in the status register, programmed using the WRSR instruction. Valid combinations yield 200 ms (WD1=0, WD0=0), 600 ms (WD1=0, WD0=1), 1.4 s (WD1=1, WD0=0), or disabled (WD1=1, WD0=1 - factory default).

Can X5043S8IZT2's EEPROM be written to while the watchdog is enabled?

Yes, X5043S8IZT2 allows simultaneous EEPROM write operations and watchdog monitoring. The CS/WDI pin serves dual roles: chip select for SPI commands and watchdog input. As long as CS transitions HIGH→LOW at least once per timeout interval, EEPROM writes proceed normally without interrupting watchdog functionality.

What is the maximum SPI clock frequency supported by X5043S8IZT2?

X5043S8IZT2 supports a maximum SPI clock frequency of 3.3 MHz across its full operating voltage range (2.7–5.5 V). This specification is validated per AC Electrical Characteristics in FN8126 Rev 3.00, with timing margins maintained under worst-case voltage and temperature conditions.