Renesas X5043M8IZ-2.7A

Overview

X5043M8IZ-2.7A from Intersil (now Renesas) is a CPU supervisor IC integrating power-on reset control, watchdog timer, supply voltage supervision, and 4Kbit SPI EEPROM in an 8-pin MSOP package. It operates from 2.7V to 5.5V, features a factory-programmed 2.93V ±2.5% VTRIP threshold, supports -40°C to +85°C industrial temperature range, and delivers 3.3MHz SPI interface speed - used for reliable microcontroller boot sequencing and nonvolatile configuration storage in embedded systems.

For engineers reviewing the X5043M8IZ-2.7A datasheet, X5043M8IZ-2.7A pinout, X5043M8IZ-2.7A application, or X5043M8IZ-2.7A equivalent, key selection criteria include its active-low RESET output, programmable VTRIP capability, 200ms reset timeout, 1.4s/600ms/200ms selectable watchdog intervals, and block-lock EEPROM protection covering 1/4, 1/2, or full memory array.

Technical Context

The X5043M8IZ-2.7A implements a dual-function CS/WDI pin that serves as both chip select and watchdog input, with falling-edge-triggered watchdog reset. Its internal power-on reset circuit asserts RESET until VCC exceeds 2.93V and remains stable for 200ms (typical), while low-voltage detection holds RESET active down to 1V VCC.

EEPROM operation uses standard SPI protocol with MSB-first transmission, 16-byte page write mode, and Direct Write™ cell technology enabling 1M write cycles and 100-year data retention. Status register bits WD0/WD1 and BL0/BL1 are nonvolatile and user-programmable via WRSR instruction to configure watchdog timeout and memory block lock settings.

Key Specifications

Pinout & Package

Package: 8-pin MSOP (3.0mm × 3.0mm, 0.65mm pitch), RoHS-compliant Pb-free plus anneal finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP809T-290I/MS and MAX6816EUK+T, the X5043M8IZ-2.7A uniquely integrates reset, watchdog, and 4Kbit EEPROM in one 8-pin MSOP - reducing BOM count, PCB area, and qualification effort versus multi-chip solutions requiring layout coordination and timing alignment.

Availability

X5043M8IZ-2.7A is available at Aetrix Electronics and suitable for industrial process controllers, network infrastructure equipment, battery-powered telemetry devices, intelligent power meters, and embedded systems requiring stable component supply with long-term lifecycle support.

Supply support for X5043M8IZ-2.7A 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, now part of Renesas Electronics, designs high-performance analog and mixed-signal ICs for industrial, communications, and computing markets.

The X5043 family was developed to consolidate power management, system supervision, and nonvolatile storage into a single compact device - targeting cost-sensitive, space-constrained embedded applications where reliability and long-term data integrity are critical.

FAQ

What is the factory-set VTRIP voltage for X5043M8IZ-2.7A?

The X5043M8IZ-2.7A ships with a factory-programmed VTRIP threshold of 2.93V ±2.5%, optimized for 3.3V system supervision. This value is stored in nonvolatile circuitry and remains stable over temperature and time unless reprogrammed using the VP=15–18V method described in the datasheet. The X5043M8IZ-2.7A maintains this setting across power cycles and retains it even after total power loss.

Does X5043M8IZ-2.7A support both active-low and active-high reset outputs?

No - the X5043M8IZ-2.7A provides only an active-low open-drain RESET output. The X5045 variant (e.g., X5045M8IZ-2.7A) offers active-high RESET, but X5043M8IZ-2.7A is strictly active-low. Its RESET pin must be externally pulled up to VCC to generate a valid logic-high signal for microcontrollers expecting active-low reset assertion. The X5043M8IZ-2.7A does not include internal pull-up or active-high drive capability.

How many watchdog timeout options does X5043M8IZ-2.7A offer, and how are they selected?

The X5043M8IZ-2.7A provides three selectable watchdog timeout periods: 200ms, 600ms, and 1.4s - configured via nonvolatile WD0/WD1 bits in the status register. These bits are programmed using the WRSR instruction and retain their setting across power cycles. The X5043M8IZ-2.7A defaults to watchdog disabled (WD0=WD1=1), requiring explicit configuration to enable any timeout interval.

Can the EEPROM in X5043M8IZ-2.7A be partially write-protected, and how is it controlled?

Yes - the X5043M8IZ-2.7A supports partial EEPROM write protection via Block Lock™, controlled by nonvolatile BL0/BL1 bits. Setting these bits protects 0%, 25%, 50%, or 100% of the 512×8 array (addresses $000–$1FF). Protection is enforced regardless of WP pin state or WREN latch status. The X5043M8IZ-2.7A allows independent read access to locked regions while blocking writes - ideal for preserving bootloader or calibration data.

What is the maximum SPI clock frequency supported by X5043M8IZ-2.7A?

The X5043M8IZ-2.7A supports a maximum SPI clock frequency of 3.3MHz across its full 2.7V–5.5V supply range and -40°C to +85°C operating temperature. This timing is guaranteed per AC Electrical Specifications (Page 14, FN8126 Rev 3.00) and enables efficient configuration loading and logging. The X5043M8IZ-2.7A maintains valid setup/hold times and output timing margins at this rate, eliminating need for clock throttling in high-speed microcontroller interfaces.