Renesas X40430S14-A

Overview

X40430S14-A from Xicor (now part of Renesas) is a triple-voltage supervisor IC with integrated 4Kbit EEPROM, watchdog timer, and manual reset input - designed for system-level power monitoring and nonvolatile configuration storage in embedded controllers. It monitors V_CC (V1), V2MON, and V3MON at factory-programmed thresholds (4.55–4.65 V, 2.95–3.05 V, 1.65–1.75 V), asserts RESET (active-HIGH), supports 400 kHz I²C interface, and operates from 2.7 V to 5.5 V.

For engineers reviewing the X40430S14-A datasheet, X40430S14-A pinout, X40430S14-A application, or X40430S14-A equivalent, this device serves as a single-chip solution for brownout detection, early power-fail warning (LOWLINE), fault logging via Fault Detection Register, and secure parameter storage - critical for telecom infrastructure, industrial PLCs, and server BIOS management.

Technical Context

The X40430S14-A implements three independent voltage comparators with hysteresis, each feeding dedicated fail outputs (LOWLINE, V2FAIL, V3FAIL), and a programmable power-on reset timeout (50/200/400/800 ms). Its watchdog logic monitors SDA/SCL activity using a minimal four-instruction restart sequence (START–SCL low–SCL high–STOP), with selectable timeouts of 25 ms, 200 ms, or 1.4 s.

EEPROM functionality uses Xicor's Direct Write™ cell architecture (100,000 write cycles, 100-year data retention), organized in 16-byte pages with 5 ms typical write cycle time. Block Lock™ protection allows locking 0 or 50% of memory (upper 256 bytes), enforced by nonvolatile BP bit and hardware WP pin.

Key Specifications

Pinout & Package

Package: 14-lead SOIC (S14-A suffix denotes SOIC-14); RoHS-compliant, body size 8.65 mm × 3.90 mm, lead pitch 1.27 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar triple-voltage supervisor with EEPROM applications.

Compared with MAX6824EUT+T and TPS3808G33DBVR, the X40430S14-A uniquely integrates triple-rail supervision, active-HIGH RESET, programmable watchdog, and 4 Kbit EEPROM in one SOIC-14 package - delivering system-level reliability without external support components.

Availability

X40430S14-A is available at Aetrix Electronics and suitable for communication equipment, industrial control systems, and computer servers requiring stable component supply, long-term lifecycle support, and guaranteed traceability.

Supply support for X40430S14-A 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

Xicor was a fabless semiconductor company specializing in nonvolatile memory and power management ICs, acquired by Renesas Electronics in 2008. Its legacy products emphasize high-reliability, low-power, and system-integration features.

The X40430 series belongs to Xicor's CPU Supervisor family, designed specifically to consolidate power monitoring, reset control, and configuration storage into a single chip for cost-sensitive, space-constrained embedded systems.

FAQ

What is the factory-default power-on reset timeout for the X40430S14-A?

The X40430S14-A ships with t_PURST set to 200 ms by default, controlled by PUP1/PUP0 bits (01 binary) in the nonvolatile Control Register. This delay ensures sufficient time for V_CC stabilization and oscillator startup before releasing the active-HIGH RESET signal. The timeout can be reconfigured to 50 ms, 400 ms, or 800 ms via I²C write to the Control Register using the documented three-step sequence involving WEL and RWEL latches.

How does the X40430S14-A handle write protection for its EEPROM array?

The X40430S14-A implements dual-layer EEPROM write protection: hardware-level via the WP pin (HIGH disables all writes), and software-level via the nonvolatile Block Protect (BP) bit. When BP = 1, the upper 256 bytes (addresses 0x100–0x1FF) are locked against writes; BP = 0 leaves entire array writable. Both protections must be disabled to perform writes - ensuring robust defense against accidental or malicious corruption during power transitions or firmware updates.

Can the voltage trip thresholds of the X40430S14-A be modified after soldering to the PCB?

Yes, the V_TRIP1, V_TRIP2, and V_TRIP3 thresholds of the X40430S14-A can be reprogrammed in-system using a defined I²C-based high-voltage programming sequence. This requires applying the target threshold voltage to the corresponding monitor pin (V_CC, V2MON, or V3MON), pulsing V_P (≥8 V) on WDO, then issuing specific slave address/byte address/data sequences over I²C. Reprogramming does not affect EEPROM data and is verified by ramping the monitored voltage and observing fail output switching points.

What is the role of the LOWLINE pin on the X40430S14-A, and how does it differ from RESET?

The LOWLINE pin on the X40430S14-A is a CMOS output that goes LOW immediately when V_CC falls below V_TRIP1, with no power-up delay circuitry - providing an early brownout warning signal. Unlike the RESET pin (which holds active for t_PURST after release), LOWLINE transitions synchronously with V_CC crossing V_TRIP1. This allows host processors to initiate graceful shutdown, save volatile data, or disable peripherals before RESET is asserted, improving system robustness during marginal supply conditions.

Does the X40430S14-A support standard I²C addressing, and what is its default slave address?

Yes, the X40430S14-A supports standard 7-bit I²C addressing with a base slave address of 0xA0 (1010000b), where the three least-significant bits are hardwired to '0' - resulting in a fixed address of 0xA0 for all operations. It responds to this address for EEPROM reads/writes and uses the same address with special preamble (1011) for accessing control registers (0x1FF) and the Fault Detection Register (0x0FF), maintaining full compatibility with standard I²C masters and SMBus controllers.