Renesas X5325S8-2.7

Overview

X5325S8-2.7 from Intersil is an active-high CPU supervisor IC integrating power-on reset control, watchdog timer, supply voltage supervision, and 32kbit SPI EEPROM in a single 8-lead SOIC package. It operates across 2.7V–5.5V, provides factory-default 2.55V–2.7V VTRIP threshold, supports 200ms power-up reset timeout, and delivers <1µA standby current with watchdog disabled - enabling reliable microcontroller monitoring in battery-powered industrial controllers.

For engineers reviewing the X5325S8-2.7 datasheet, X5325S8-2.7 pinout, X5325S8-2.7 application, or X5325S8-2.7 equivalent, this device serves as a system-level supervisory solution where deterministic reset assertion, programmable voltage thresholds, nonvolatile configuration storage, and SPI-compatible memory coexist on one die - critical for embedded systems requiring fail-safe boot integrity and field-adjustable trip points.

Technical Context

The X5325S8-2.7 implements a dual-function CS/WDI pin that enables both chip select and watchdog input via HIGH-to-LOW transitions, with three selectable watchdog timeout periods (200ms/600ms/1.4s) controlled by nonvolatile WD0/WD1 bits. Its low-VCC detection circuit asserts RESET/RESET down to 1V and holds it active until VCC exceeds the programmed VTRIP for 200ms.

Internally, the device combines a serial EEPROM array organized as 4k × 8 with Intersil's Block Lock™ protection, supporting page writes (32-byte), self-timed 10ms write cycles, and 100,000 endurance cycles. The status register includes volatile WIP/WEL flags and nonvolatile BL0/BL1 bits for memory partitioning, all accessible via standard SPI opcodes (READ/WRITE/WRSR/RDSR).

Key Specifications

Pinout & Package

Package: 8-lead SOIC (Pb-free, RoHS compliant), 3.9mm × 4.9mm footprint, compatible with standard reflow soldering.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6361KA29+T and STM8AF6266TCY, the X5325S8-2.7 uniquely delivers verified reset timing, field-programmable VTRIP, and secure EEPROM in one component - eliminating design compromises between simplicity, configurability, and functional safety compliance.

Availability

X5325S8-2.7 is available at Aetrix Electronics and suitable for industrial PLC controllers, medical infusion pumps, smart energy meters, and automotive body control modules requiring stable component supply with long-term lifecycle support.

Supply support for X5325S8-2.7 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) designs high-performance analog and mixed-signal ICs for industrial, computing, and communications markets.

The X5325 product line targets embedded systems needing integrated power supervision and nonvolatile configuration storage - reducing external component count while enhancing system-level reliability and field serviceability.

FAQ

What is the default VTRIP voltage range for the X5325S8-2.7?

The X5325S8-2.7 ships with a factory-default VTRIP range of 2.55V to 2.7V, optimized for 3V system rails. This threshold is nonvolatile and can be reprogrammed using the VP-based sequence documented in the FN8131 datasheet. The device guarantees reset assertion down to 1V VCC and holds RESET active for 200ms after VCC exceeds VTRIP.

Does the X5325S8-2.7 support active-high or active-low reset output?

The X5325S8-2.7 provides an active-high RESET output, distinguishing it from the X5323 series which offers active-low RESET. This polarity aligns with many modern microcontrollers and PMICs requiring high-asserted reset signals. The output is open-drain, allowing wired-OR configurations and compatibility with pull-up resistors to various voltage domains.

How does the watchdog timer function on the X5325S8-2.7?

The X5325S8-2.7 watchdog timer monitors the CS/WDI pin for HIGH-to-LOW transitions. If no transition occurs within the selected timeout period (200ms/600ms/1.4s), it asserts the RESET signal. Timeout selection is stored in nonvolatile WD0/WD1 bits and persists across power cycles. The timer is factory-disabled (WD1=1, WD0=1) and must be enabled via WRSR instruction.

Can the EEPROM in the X5325S8-2.7 be protected against accidental writes?

Yes, the X5325S8-2.7 implements multiple write protection layers: power-up/power-down circuitry prevents writes during voltage transitions; the WP pin combined with the nonvolatile WPEN bit enables in-circuit programmable ROM mode; and Block Lock™ bits (BL0/BL1) allow selective protection of 0%, 25%, 50%, or 100% of the 32kbit EEPROM array - all configurable via WRSR instruction.

What SPI interface modes does the X5325S8-2.7 support?

The X5325S8-2.7 supports SPI modes 0,0 (CPOL=0, CPHA=0) and 1,1 (CPOL=1, CPHA=1), matching common microcontroller configurations. Data is transferred MSB-first, with SI latching on SCK rising edge and SO driving on SCK falling edge. Maximum clock frequency is 2MHz, and the device includes built-in timing margins (tSU=50ns, tH=50ns) for robust operation across temperature and voltage ranges.