Renesas X5043S8I-2.7A

Overview

X5043S8I-2.7A from Intersil is a CPU supervisor IC integrating power-on reset control, watchdog timer, supply voltage supervision, and 4Kbit SPI EEPROM in an 8-lead SOIC package. It features 2.85V–3.0V V_TRIP, -40°C to +85°C operation, and active-low RESET output - used in industrial process controllers to ensure deterministic microcontroller startup and brownout recovery.

For engineers reviewing the X5043S8I-2.7A datasheet, X5043S8I-2.7A pinout, X5043S8I-2.7A application, or X5043S8I-2.7A equivalent, key selection criteria include confirmed V_TRIP threshold (2.85–3.0V), watchdog timeout configurability (200ms/600ms/1.4s), EEPROM block-lock protection granularity, and SOIC-8 compatibility with SPI-based host interfaces.

Technical Context

The X5043S8I-2.7A implements a dual-function CS/WDI pin for chip select and watchdog input, with internal nonvolatile status register bits (WD0/WD1) selecting one of three timeout intervals or disabling the watchdog. Its low-voltage detection circuit asserts RESET until V_CC exceeds the programmed V_TRIP for 200ms, and remains valid down to V_CC = 1V.

EEPROM operation uses Intersil's Direct Write™ cell architecture with 1M write endurance and 100-year data retention. Block lock protection (BL0/BL1 bits) enables selective write-protection of 0%, 25%, 50%, or 100% of the 512 × 8-bit array, enforced via hardware (WP pin) and software (WREN/WRSR) controls.

Key Specifications

Pinout & Package

Package: 8-lead SOIC (Pb-free, RoHS-compliant), 3.9mm × 4.9mm body, 1.27mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6373US29D3+ and MCP9808-E/P, the X5043S8I-2.7A uniquely combines field-adjustable reset threshold, 1M-cycle EEPROM, and hardware-enforced block lock - making it the only viable option for industrial systems requiring certified data integrity and adaptive brownout response.

Availability

X5043S8I-2.7A is available at Aetrix Electronics and suitable for industrial process control, network infrastructure, smart metering, and battery-powered data acquisition requiring stable component supply over extended production lifecycles.

Supply support for X5043S8I-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 (now part of Renesas Electronics) is a semiconductor manufacturer specializing in precision analog, power management, and interface ICs for industrial, communications, and computing markets.

The X5043/X5045 product line was designed to consolidate power monitoring, reset generation, watchdog safety, and nonvolatile storage into a single die - targeting space-constrained embedded systems where reliability and data integrity are mission-critical.

FAQ

What is the exact V_TRIP voltage range for X5043S8I-2.7A?

The X5043S8I-2.7A has a factory-programmed V_TRIP range of 2.85V to 3.0V (±2.5%) - verified per FN8126 Rev 3.00, Page 4, Ordering Information table. This threshold is optimized for 2.7V–5.5V V_CC operation and can be reprogrammed to custom values using the VP = 15–18V procedure described on Page 6.

Does X5043S8I-2.7A support SPI communication at 3.3V logic levels?

Yes, X5043S8I-2.7A supports full SPI operation at 3.3V V_CC, including 3.3MHz clock rate, push-pull SO output with VOH ≥ V_CC − 0.8V, and VIH ≥ V_CC × 0.7 - all confirmed in DC and AC Electrical Specifications (Pages 13–14). No level-shifting is required for 3.3V microcontrollers.

How is the watchdog timer configured on X5043S8I-2.7A?

The watchdog timer on X5043S8I-2.7A is configured via nonvolatile WD0/WD1 bits in the status register, set using the WRSR instruction. Valid timeouts are 200ms (WD1=1,WD0=0), 600ms (WD1=0,WD0=1), 1.4s (WD1=0,WD0=0), or disabled (WD1=1,WD0=1 - factory default). The setting persists across power cycles.

Can the EEPROM in X5043S8I-2.7A be partially write-protected?

Yes, X5043S8I-2.7A supports partial write protection via Block Lock™ using BL0/BL1 bits. Configurations include: 0% (BL1=0,BL0=0), 25% (BL1=0,BL0=1, addresses $180–$1FF), 50% (BL1=1,BL0=0, $100–$1FF), or 100% (BL1=1,BL0=1, $000–$1FF) - all documented in Table 2 on Page 9.

What is the minimum V_CC at which X5043S8I-2.7A maintains valid RESET output?

X5043S8I-2.7A guarantees valid RESET assertion down to V_CC = 1V, as specified in "Reset Signal Valid to V_CC = 1V" (Page 1, Features) and VRVALID parameter (Page 16, tRPD section). This ensures fail-safe shutdown during deep brownout events before MCU logic fails.