Renesas X5325S8IZT1

Overview

X5325S8IZT1 from Intersil is a CPU supervisor IC with integrated 32kbit SPI EEPROM, combining power-on reset control, watchdog timer, supply voltage supervision, and block-lock protected memory in a single 8-lead SOIC package. It provides active-high RESET output, operates from 2.7V to 5.5V, supports 2MHz SPI interface, and delivers <1µA standby current with watchdog disabled - used in industrial microcontroller systems requiring reliable brown-out protection and nonvolatile configuration storage.

For engineers reviewing the X5325S8IZT1 datasheet, X5325S8IZT1 pinout, X5325S8IZT1 application, or X5325S8IZT1 equivalent, this page details its verified reset threshold (2.55–2.7V), watchdog timeout options (200ms/600ms/1.4s), EEPROM endurance (100,000 cycles), Block Lock™ protection granularity, and SOIC-8 pin mapping per FN8131 Rev 3.00.

Technical Context

The X5325S8IZT1 implements a dual-function CS/WDI pin for chip select and watchdog input, with volatile flag bit reporting reset cause (watchdog vs. low-VCC). Its reset logic asserts RESET/RESET at VCC ≈ 1V on power-up and holds it active for 100–280ms until VCC exceeds the programmable trip point and stabilizes for 200ms.

EEPROM operation uses SPI Mode 0,0 or 1,1 with MSB-first protocol; write enable latch (WEL) must be set before WRITE or WRSR commands; page writes support 32-byte bursts with self-timed 10ms typical cycle time. The status register includes nonvolatile WD0/WD1 bits (factory-default disabled) and BL0/BL1 bits controlling quarter/half/full array lock.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6369KA22+T and STM8AF5288TCY, X5325S8IZT1 uniquely combines field-programmable VTRIP, 32kbit Block Lock™ EEPROM, and SOIC-8 packaging - enabling precise brown-out tuning, robust nonvolatile storage, and minimal board space usage without MCU integration overhead.

Availability

X5325S8IZT1 is available at Aetrix Electronics and suitable for industrial automation, medical device, smart metering, and automotive body control applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for X5325S8IZT1 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 power management, precision analog, and mixed-signal ICs for industrial, computing, and communications markets.

The X5325 series belongs to Intersil's CPU Supervisor family, designed to replace discrete reset ICs and serial EEPROMs in microcontroller-based systems - targeting cost-sensitive, space-constrained embedded applications needing reliable power monitoring and nonvolatile configuration storage.

FAQ

What is the reset output polarity of the X5325S8IZT1?

The X5325S8IZT1 features an active-HIGH RESET output (labeled RESET/RESET on pin 8), which goes HIGH during power-up, brown-out, or watchdog timeout. This differs from the X5323 variant, which provides active-LOW reset. The output is open-drain, requiring an external pull-up resistor for proper logic level translation in the host system. The X5325S8IZT1 maintains this polarity across all operating conditions and temperature ranges specified in FN8131 Rev 3.00.

Can the reset threshold voltage (VTRIP) of the X5325S8IZT1 be changed after manufacturing?

Yes, the X5325S8IZT1 supports field reprogramming of its VTRIP voltage using a dedicated VP programming sequence involving SCK, SI, and CS/WDI pins with 15–18V pulses. This allows adjustment to higher thresholds (e.g., from 2.63V to 2.92V) or resetting to native levels. The procedure is documented in FN8131 Rev 3.00 Pages 4–5 and requires no special equipment beyond controlled voltage sources. The X5325S8IZT1 retains the new setting indefinitely, even after power cycling.

How does the watchdog timer function in the X5325S8IZT1?

The X5325S8IZT1 watchdog timer monitors the CS/WDI pin for HIGH-to-LOW transitions and triggers RESET/RESET if none occurs within the selected timeout period (200ms, 600ms, or 1.4s). Timeout selection is controlled by nonvolatile WD0/WD1 bits in the status register, which remain unchanged across power cycles. The timer is factory-disabled (WD1=1, WD0=1) and must be explicitly enabled via WRSR command. The X5325S8IZT1 also provides a volatile FLAG bit to distinguish watchdog resets from low-VCC events in firmware.

What EEPROM protection mechanisms does the X5325S8IZT1 provide?

The X5325S8IZT1 implements three-tiered EEPROM protection: (1) Power-up/power-down write inhibit circuitry prevents spurious writes during supply ramp; (2) Block Lock™ protection controlled by BL0/BL1 bits locks 0%, 25%, 50%, or 100% of the 32kbit array; (3) In-circuit programmable ROM mode activated by WP pin LOW + WPEN bit HIGH disables all status register writes. These features ensure that critical configuration data stored in the X5325S8IZT1 remains intact during system noise, brown-outs, or accidental firmware updates.

Is the X5325S8IZT1 compatible with standard SPI microcontrollers?

Yes, the X5325S8IZT1 supports standard SPI Modes 0,0 and 1,1 with MSB-first data transfer, 2MHz maximum clock rate, and standard timing parameters (tSU = 50ns, tH = 50ns). It interfaces directly with common microcontrollers including STM32, PIC, MSP430, and AVR families without level-shifting or protocol translation. The X5325S8IZT1's SO pin uses push-pull output, eliminating the need for external pull-ups on the data line, and its CS/WDI pin accepts standard logic-level signals per FN8131 Rev 3.00 Section "Pin Descriptions".