Renesas X5043S8I-2.7T1

Overview

X5043S8I-2.7T1 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 features a 2.85V–3.0V VTRIP threshold, active-low RESET output, -40°C to +85°C operating temperature, and 3.3MHz SPI interface - deployed in industrial process controllers for brownout protection and nonvolatile configuration storage.

For engineers reviewing the X5043S8I-2.7T1 datasheet, X5043S8I-2.7T1 pinout, X5043S8I-2.7T1 application, or X5043S8I-2.7T1 equivalent, this page delivers verified functional identity, validated pin roles, confirmed timing parameters, and real-world use context - all extracted from FN8126 Rev 3.00 and cross-verified against Renesas official documentation.

Technical Context

The X5043S8I-2.7T1 implements a dual-function supervisory architecture: its POR circuit asserts RESET for ≥200ms after VCC exceeds 2.85V, while its watchdog timer monitors CS/WDI transitions with four selectable timeout intervals (200ms/600ms/1.4s/disabled) controlled by nonvolatile WD0/WD1 bits. The device uses an internal voltage comparator with ±2.5% tolerance on its 2.85V trip point.

Its 512 × 8-bit EEPROM array employs Intersil's Direct Write™ cell technology, enabling 1M write cycles and 100-year data retention. Block lock protection (BL0/BL1 bits) allows selective write-protection of 0%, 25%, 50%, or 100% of memory, enforced via hardware (WP pin) and software (WREN/WRSR) mechanisms.

Key Specifications

Pinout & Package

8-lead SOIC package (3.9mm × 4.9mm, 1.27mm pitch), RoHS-compliant Pb-free plus anneal finish per IPC/JEDEC J-STD-020.

Key Features

Applications

Equivalent & Alternatives

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

Compared with X5043S8I-2.7T1, MAX6375US29D3+ offers identical packaging and supply range but sacrifices field-trim capability, while STM802SWX6F increases system complexity by decoupling supervision and memory functions - making X5043S8I-2.7T1 optimal for space-constrained, field-calibratable industrial designs.

Availability

X5043S8I-2.7T1 is available at Aetrix Electronics and suitable for industrial process controllers, network infrastructure equipment, and medical safety monitors requiring stable component supply, long-term lifecycle support, and RoHS-compliant manufacturing.

Supply support for X5043S8I-2.7T1 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 (formerly Intersil) is a global semiconductor leader specializing in microcontrollers, analog, power management, and trusted computing solutions for industrial, automotive, and infrastructure markets.

The X5043 family was designed specifically for embedded systems needing consolidated power supervision and nonvolatile configuration storage - targeting cost-sensitive, reliability-critical applications where board space and component count are constrained.

FAQ

What is the exact VTRIP voltage for X5043S8I-2.7T1 and how is it programmed?

The X5043S8I-2.7T1 has a factory-programmed VTRIP of 2.85V ±2.5%, corresponding to the "-2.7A" suffix. This threshold can be reprogrammed upward using a 15–18V programming voltage applied to the WP pin while issuing a WREN command followed by writing 00h to address 01h. The procedure requires precise VCC biasing at the target trip voltage and is documented in FN8126 Rev 3.00 Section 6.

Does X5043S8I-2.7T1 support both active-low and active-high RESET outputs?

No - X5043S8I-2.7T1 provides only an active-low RESET output (open-drain). The "X5045" variant in the same family offers active-high RESET, but X5043S8I-2.7T1 is strictly active-low. Its RESET pin asserts low during power-up, brownout, or watchdog timeout and requires an external pull-up resistor to VCC for proper logic-level translation.

What is the maximum SPI clock frequency supported by X5043S8I-2.7T1?

X5043S8I-2.7T1 supports a maximum SPI clock frequency of 3.3MHz across its full 2.7V–5.5V VCC range, as specified in the AC Electrical Characteristics table (Page 14, FN8126 Rev 3.00). This allows fast read/write operations without MCU clock scaling, and timing parameters (tSU, tH, tV) are guaranteed at this rate under recommended operating conditions.

How does the watchdog timer in X5043S8I-2.7T1 get reset and what are its timeout options?

The watchdog timer in X5043S8I-2.7T1 is reset by a falling edge on the CS/WDI pin. Its timeout interval is selected via nonvolatile WD0/WD1 bits in the status register: 200ms (WD1=1, WD0=0), 600ms (WD1=0, WD0=1), 1.4s (WD1=0, WD0=0), or disabled (WD1=1, WD0=1 - factory default). These settings persist across power cycles and require WRSR instruction to modify.

Can X5043S8I-2.7T1's EEPROM be partially write-protected, and how is that configured?

Yes - X5043S8I-2.7T1 supports partial EEPROM write protection via two nonvolatile block lock bits (BL0/BL1) in the status register. Setting BL1/BL0 to 00 protects none, 01 protects upper quarter ($180–$1FF), 10 protects upper half ($100–$1FF), and 11 protects entire array ($000–$1FF). Protection is enforced simultaneously with WP pin state and WEL latch status per Table 2 in FN8126.