Renesas X4163P-4.5A

Overview

X4163P-4.5A from Xicor is a CPU supervisor IC integrating power-on reset control, watchdog timer, supply voltage supervision, and 16 Kbit serial EEPROM in a single 8-pin SOIC package. It features a factory-set 4.5 V reset threshold, 400 kHz I²C interface, <20 µA standby current (watchdog enabled), and 5 ms typical EEPROM write cycle time. It is used in embedded microcontroller systems requiring reliable power sequencing and nonvolatile configuration storage.

For engineers reviewing the X4163P-4.5A datasheet, X4163P-4.5A pinout, X4163P-4.5A application, or X4163P-4.5A equivalent, key selection criteria include reset threshold accuracy, watchdog timeout configurability, EEPROM page-write capability, hardware write protection via WP pin, and compatibility with 2.7–5.5 V system rails.

Technical Context

The X4163P-4.5A implements a dual-function reset architecture: power-on reset with 250 ms delay and low-V_CC detection asserting RESET/RESET below 4.5 V (±1.5% tolerance per datasheet). Its watchdog timer supports three fixed timeout intervals (200 ms, 600 ms, 1.4 s) selected via nonvolatile WD1/WD0 bits in the control register.

EEPROM operation uses a 64-byte page-write mode with self-timed internal write cycles; block lock protection covers configurable memory segments (first 64 B to full 2 KB array) controlled by BP2–BP0 bits. The device operates as an I²C slave with 7-bit address 0xA0–0xA7 (S0/S1 selectable), and RESET/RESET is an open-drain active-low output with guaranteed validity down to V_CC = 1 V.

Key Specifications

Pinout & Package

Package: 8-lead JEDEC SOIC (3.9 mm × 4.9 mm, 1.27 mm pitch).

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 STM8T142M2U6, the X4163P-4.5A uniquely balances precision 4.5 V supervision, field-adjustable threshold, and ample 16 Kbit EEPROM - making it optimal for industrial and medical designs where voltage margin, data retention, and minimal firmware dependency are critical.

Availability

X4163P-4.5A is available at Aetrix Electronics and suitable for industrial PLC controllers, medical infusion pumps, smart energy meters, automotive body control modules, and battery-backed IoT gateways requiring stable component supply across extended product lifecycles.

Supply support for X4163P-4.5A 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 Inc. was a fabless semiconductor company specializing in nonvolatile memory and power management ICs, acquired by Intersil in 2001 and later integrated into Renesas Electronics. Known for high-reliability EEPROM and supervisor solutions.

The X4163/5 family was designed for embedded systems needing consolidated power supervision, watchdog safety, and persistent data storage - targeting cost-sensitive, space-constrained applications where reliability under voltage stress is paramount.

FAQ

What is the factory-programmed reset threshold voltage for X4163P-4.5A?

The X4163P-4.5A is factory-programmed with a nominal reset threshold of 4.5 V, with ±1.5% tolerance over temperature and supply variations. This value is stored in nonvolatile trim circuitry and remains stable across operating life unless reprogrammed using the documented V_TRIP adjustment sequence involving WP pin voltage injection and specific I²C commands.

Can the watchdog timer timeout period be changed after soldering X4163P-4.5A onto the PCB?

Yes, the watchdog timeout period of X4163P-4.5A can be reconfigured in-system via I²C writes to the control register (address FFFFh). WD1 and WD0 bits support three intervals: 200 ms, 600 ms, or 1.4 s. The change persists through power cycles and requires no hardware modification - only proper WEL/RWEL bit setup before writing the new configuration.

Does X4163P-4.5A support standard I²C addressing, and how many devices can share one bus?

X4163P-4.5A uses standard 7-bit I²C addressing with base code 0xA0. Pins S0 and S1 allow four unique addresses (0xA0–0xA7), enabling up to four X4163P-4.5A devices on a single I²C bus without address conflict. Each device responds only to its configured address, supporting distributed supervision in multi-node systems.

How does hardware write protection work on X4163P-4.5A, and what happens when WP is pulled HIGH?

When WP is pulled HIGH and the WPEN bit is set in the control register, X4163P-4.5A enters hardware write-protected mode: all EEPROM writes and control register modifications are blocked, regardless of WEL bit state. This prevents accidental overwrites during field operation or firmware updates - a critical safeguard for certified medical or industrial equipment.

Is the EEPROM in X4163P-4.5A compatible with standard 2-wire (I²C) protocols, and what is the maximum write speed?

Yes, the 16 Kbit EEPROM in X4163P-4.5A fully complies with standard I²C protocol (400 kHz fast-mode) and supports byte and 64-byte page writes. Maximum write speed is governed by the internal 5 ms typical self-timed cycle - no external timing control is needed, and acknowledge polling allows the host to determine completion without fixed delays.