Renesas X5083S8IZT1

Overview

X5083S8IZT1 from Intersil is a CPU supervisor IC integrating power-on reset control, watchdog timer, supply voltage supervision, and 8Kbit SPI EEPROM in a single SOIC-8 package. It provides active-low open-drain RESET output, supports 3.3 MHz SPI interface, offers programmable VTRIP thresholds (e.g., 4.38 V ±2.5%), and delivers <50 µA standby current with watchdog enabled.

For engineers reviewing the X5083S8IZT1 datasheet, X5083S8IZT1 pinout, X5083S8IZT1 application, or X5083S8IZT1 equivalent, this device serves as a system-level reliability enhancer for microcontroller-based designs requiring brownout protection, fail-safe boot sequencing, nonvolatile parameter storage, and autonomous watchdog recovery - especially where board space and BOM count are constrained.

Technical Context

The X5083S8IZT1 implements a dual-function CS/WDI pin that enables both SPI command selection and watchdog timer reset via HIGH-to-LOW transitions. Its internal voltage monitor asserts RESET when VCC drops below the factory-set or user-programmed VTRIP threshold (e.g., 4.38 V), holding it active for ≥200 ms after VCC recovers.

Watchdog timeout is determined by nonvolatile WD1/WD0 bits in the status register, supporting three fixed intervals (200 ms, 600 ms, 1.4 s) or disabled state; the setting persists across power cycles. The integrated 8Kbit EEPROM uses Block Lock™ protection, allowing selective locking of memory pages or quadrants via SPI commands without external hardware.

Key Specifications

Pinout & Package

Package: 8-lead SOIC (RoHS-compliant, M8.15E footprint, body width 3.9 mm).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6361KA29+T and STM6803RWDY6F, the X5083S8IZT1 uniquely combines field-programmable VTRIP, 8 Kbit Block Lock™ EEPROM, and sub-50 µA watchdog-enabled standby - making it optimal for industrial and telecom applications demanding configurability, data integrity, and long-term power efficiency.

Availability

X5083S8IZT1 is available at Aetrix Electronics and suitable for industrial process control, network infrastructure equipment, set-top box manufacturing, and battery-powered IoT sensor nodes requiring stable component supply across extended product lifecycles.

Supply support for X5083S8IZT1 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 is a leader in precision analog and power management ICs, serving industrial, infrastructure, and high-end consumer markets with high-reliability solutions.

The X5083S8IZT1 belongs to Intersil's CPU Supervisor family, designed specifically to consolidate power monitoring, watchdog safety, and nonvolatile storage into one IC for microcontroller-based systems operating in harsh or space-constrained environments.

FAQ

What is the factory-default VTRIP voltage for X5083S8IZT1?

The X5083S8IZT1 is shipped with a factory-default VTRIP of 4.38 V ±2.5%, corresponding to the "-4.5" suffix variant. This threshold is optimized for 5 V systems and remains stable over temperature and time unless reprogrammed using the VP = 15–18 V sequence on the WP pin. The X5083S8IZT1 maintains this setting across power cycles due to nonvolatile storage of the trip-point configuration.

Does X5083S8IZT1 support SPI mode 0,0 only or both 0,0 and 1,1?

The X5083S8IZT1 supports both SPI modes: mode 0,0 (CPOL = 0, CPHA = 0) and mode 1,1 (CPOL = 1, CPHA = 1), as explicitly stated in the datasheet Features section. This dual-mode compatibility allows direct interfacing with diverse microcontrollers without level-shifting or protocol translation. The X5083S8IZT1 interprets clock polarity and phase based on the first instruction received after CS activation.

How does the watchdog timer in X5083S8IZT1 get reset during normal operation?

The watchdog timer in X5083S8IZT1 is reset exclusively by a HIGH-to-LOW transition on the CS/WDI pin - not by toggling CS alone or writing to registers. This transition must occur before expiration of the selected timeout interval (200 ms, 600 ms, or 1.4 s). A falling edge on CS/WDI restarts the timer counter; failure to do so results in RESET assertion. The X5083S8IZT1 does not require periodic SPI commands to clear the watchdog - simplifying firmware integration.

Can X5083S8IZT1's EEPROM be written to while the watchdog is enabled?

Yes, X5083S8IZT1 allows EEPROM writes while the watchdog is enabled, provided the CS/WDI pin is toggled within the timeout window before and after the write sequence. The watchdog monitors only CS/WDI activity - not SPI bus traffic - so standard WREN → WRITE → CS HIGH sequences proceed normally. However, if CS remains static longer than the timeout, RESET activates and halts all operations. The X5083S8IZT1's design ensures coexistence of memory access and watchdog supervision without conflict.

What is the minimum VCC required for X5083S8IZT1 to assert a valid RESET signal?

The X5083S8IZT1 asserts RESET down to VCC = 1 V, as confirmed in the datasheet Features and Electrical Specifications sections. Below this voltage, internal circuitry cannot guarantee proper comparator or latch operation. At VCC ≥ 1 V, RESET remains active during brownout and releases only after VCC exceeds the programmed VTRIP threshold for ≥200 ms. This 1 V validity floor makes the X5083S8IZT1 suitable for deep-brownout detection scenarios where other supervisors cut out earlier.