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Home > Products > Integrated Circuits (ICs) > Power Management (PMIC) > Supervisors

Renesas X4043P-2.7A

Name: X4043P-2.7A
Brand: Renesas
SKU: X4043P-2.7A
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: X4043P-2.7A

Manufacturer:: Renesas

Category:: Supervisors

Package:: 8-DIP (0.300", 7.62mm)

Datasheet:: X4043P-2.7A.pdf

Description:: IC SUPERVISOR 1 CHANNEL 8DIP

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Product details

Overview

X4043P-2.7A from Intersil (now Renesas) is a CPU supervisor IC integrating power-on reset control, watchdog timer, supply voltage supervision, and 4kbit serial EEPROM with Block Lock™ protection. It operates from 2.7V to 5.5V, features a 2.85–3.0V reset threshold, delivers active current of 3mA, standby current <20µA (watchdog on), and supports 400kHz I²C interface. It is used in microcontroller-based embedded systems requiring reliable power sequencing and nonvolatile configuration storage.

For engineers reviewing the X4043P-2.7A datasheet, X4043P-2.7A pinout, X4043P-2.7A application, or X4043P-2.7A equivalent, key selection considerations include its active-low RESET output, programmable VTRIP threshold, 16-byte page write EEPROM, watchdog timeout options (200ms/600ms/1.4s), and compatibility with standard I²C bus timing and addressing.

Technical Context

The X4043P-2.7A implements a dual-function reset architecture: power-on reset holds RESET active for ≥250ms after VCC stabilization, while low-VCC detection asserts RESET when VCC drops below 2.85–3.0V and sustains it until VCC exceeds VTRIP for ≥200ms. Its watchdog timer monitors SDA/SCL activity using a state machine that resets only upon valid I²C start-stop sequences - not mere clock toggling.

EEPROM operation uses Intersil's Direct Write™ cell technology, enabling 1,000,000 write cycles and 100-year data retention. Block Lock™ protection is controlled via nonvolatile BP2–BP0 bits, allowing selective write lock of 16–128 byte blocks or full array, independent of WP pin state. The control register at address 1FFh (with preamble 1011) governs both watchdog period (WD1/WD0) and block lock settings.

Key Specifications

Parameter	Value and Actual Design Meaning
VCC Range	2.7V to 5.5V - supports single-supply operation across 3.3V and 5V logic domains without level shifting.
Reset Threshold (VTRIP)	2.85V to 3.0V - factory-programmed for 3.3V system brownout detection; reprogrammable via high-voltage sequence on WP pin.
Watchdog Timeout	Selectable: 200ms / 600ms / 1.4s - configured via nonvolatile WD1/WD0 bits; disabled by default.
EEPROM Capacity	4kbit (512 × 8) - organized as 512 bytes; supports 16-byte page writes with self-timed 5ms typical cycle time.
I²C Interface	400kHz maximum - fully compliant with Fast-mode I²C protocol; open-drain SDA/SCL require external pull-ups.
Standby Current	<20µA (watchdog enabled), <1µA (watchdog disabled) - enables ultra-low-power battery-backed operation.
RESET Output	Active-low, open-drain - requires external pull-up; remains valid down to VCC = 1V for fail-safe reset assertion.

Pinout & Package

Package: 8-pin PDIP (Plastic Dual In-line Package), RoHS-compliant, Pb-free plus anneal finish.

Pin/Terminal	Circuit Role	Design Meaning
1, 2	NC	No internal connection - must be left unconnected; no routing or grounding required.
3	RESET	Active-low open-drain reset output - asserts during power-on, brownout (VCC < VTRIP), or watchdog timeout; requires external pull-up resistor.
4	VSS	Ground reference - primary return path for all internal circuits and I²C interface.
5	SDA	Serial Data bidirectional I/O - open-drain, wire-OR capable; carries command/data/address on I²C bus.
6	SCL	Serial Clock input - synchronous timing signal for I²C read/write operations; master-generated only.
7	WP	Write Protect input - HIGH disables all writes (EEPROM and control register); LOW enables write operations.
8	VCC	Power supply input - supplies all internal circuitry; voltage range 2.7V–5.5V defines operating window and reset threshold behavior.

Key Features

Feature	Design Value
Programmable VTRIP threshold	Factory-set at 2.85–3.0V; user-adjustable via 15–18V pulse on WP pin - enables precise brownout tuning without external components.
Block Lock™ EEPROM protection	Nonvolatile BP2–BP0 bits enable hardware-level write lock of 16–128 byte blocks or full array - prevents accidental firmware corruption during field updates.
Self-timed EEPROM write	5ms typical write cycle with automatic internal timing - eliminates need for host MCU to manage write delays or polling overhead.
Watchdog restart protocol	Requires full I²C START–SCL LOW–SCL HIGH–STOP sequence - prevents false clears from noise or partial bus activity.
Power-fail safe write abort	Writes automatically terminate and roll back if VCC drops below VTRIP during programming - ensures EEPROM integrity under brownout conditions.

Applications

Industrial PLC Controller	Medical Infusion Pump
Use Scenario: Microcontroller-based PLC executes real-time I/O control with firmware stored in external flash; configuration parameters and calibration data retained in nonvolatile memory. IC Role / Device Role / Timing Role: X4043P-2.7A provides power-on reset sequencing, brownout detection at 2.85V, and secure EEPROM storage for calibration coefficients and runtime logs. Use Value: Prevents erratic PLC behavior during line sags; ensures parameter persistence across power cycles; blocks unauthorized EEPROM writes via Block Lock™ during firmware updates.	Use Scenario: Battery-powered infusion pump delivers precise drug dosing; requires fail-safe reset during low-battery conditions and tamper-resistant storage of dose history and safety limits. IC Role / Device Role / Timing Role: X4043P-2.7A asserts RESET when battery voltage falls below 2.85V, halts motor control, and stores critical event timestamps in protected EEPROM pages. Use Value: Guarantees immediate shutdown before unsafe operation; retains audit trail even after deep discharge; WP pin enables hardware-enforced write lock during clinical mode.
Automotive Body Control Module	Smart Energy Meter
Use Scenario: BCM manages door locks, lighting, and window controls; powered from vehicle battery with wide voltage transients (9–16V); includes EEPROM for user preferences and fault logs. IC Role / Device Role / Timing Role: X4043P-2.7A supervises 3.3V LDO output, detects undervoltage during cranking, and stores seat/mirror position data in 128-byte locked EEPROM block. Use Value: Maintains functional safety during engine start (VCC dip); preserves user settings across ignition cycles; prevents EEPROM corruption from EMI-induced bus glitches via watchdog monitoring.	Use Scenario: Revenue-grade meter records kWh consumption, tariff schedules, and tamper events; operates from AC-derived 3.3V rail with backup supercapacitor. IC Role / Device Role / Timing Role: X4043P-2.7A provides brownout reset at 2.85V during capacitor discharge, triggers EEPROM write of final energy reading, and locks memory during power transition. Use Value: Ensures accurate billing data capture before power loss; meets IEC 62056-21 data integrity requirements; eliminates need for external reset supervisor + EEPROM discrete solution.

Industrial PLC Controller

Medical Infusion Pump

Use Scenario: Microcontroller-based PLC executes real-time I/O control with firmware stored in external flash; configuration parameters and calibration data retained in nonvolatile memory.

IC Role / Device Role / Timing Role: X4043P-2.7A provides power-on reset sequencing, brownout detection at 2.85V, and secure EEPROM storage for calibration coefficients and runtime logs.

Use Value: Prevents erratic PLC behavior during line sags; ensures parameter persistence across power cycles; blocks unauthorized EEPROM writes via Block Lock™ during firmware updates.

Use Scenario: Battery-powered infusion pump delivers precise drug dosing; requires fail-safe reset during low-battery conditions and tamper-resistant storage of dose history and safety limits.

IC Role / Device Role / Timing Role: X4043P-2.7A asserts RESET when battery voltage falls below 2.85V, halts motor control, and stores critical event timestamps in protected EEPROM pages.

Use Value: Guarantees immediate shutdown before unsafe operation; retains audit trail even after deep discharge; WP pin enables hardware-enforced write lock during clinical mode.

Automotive Body Control Module

Smart Energy Meter

Use Scenario: BCM manages door locks, lighting, and window controls; powered from vehicle battery with wide voltage transients (9–16V); includes EEPROM for user preferences and fault logs.

IC Role / Device Role / Timing Role: X4043P-2.7A supervises 3.3V LDO output, detects undervoltage during cranking, and stores seat/mirror position data in 128-byte locked EEPROM block.

Use Value: Maintains functional safety during engine start (VCC dip); preserves user settings across ignition cycles; prevents EEPROM corruption from EMI-induced bus glitches via watchdog monitoring.

Use Scenario: Revenue-grade meter records kWh consumption, tariff schedules, and tamper events; operates from AC-derived 3.3V rail with backup supercapacitor.

IC Role / Device Role / Timing Role: X4043P-2.7A provides brownout reset at 2.85V during capacitor discharge, triggers EEPROM write of final energy reading, and locks memory during power transition.

Use Value: Ensures accurate billing data capture before power loss; meets IEC 62056-21 data integrity requirements; eliminates need for external reset supervisor + EEPROM discrete solution.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
MAX6361KA29+T	Fixed 2.93V reset threshold; no VTRIP programmability; 1kbit EEPROM; 100kHz I²C only	Lacks adjustable brownout point and fast-mode I²C - unsuitable where precise VTRIP tuning or high-speed configuration reads are required	Choose only if fixed 2.93V threshold suffices and EEPROM size/throughput demands are minimal
STM8T142M2U6	Integrated 8-bit MCU core; 2kbit EEPROM; 2.9V reset; no external watchdog restart protocol	Requires firmware development; lacks dedicated I²C watchdog restart logic - increases validation burden for safety-critical use	Select when embedded processing capability is needed alongside supervision, not as drop-in replacement

Compared with MAX6361KA29+T and STM8T142M2U6, the X4043P-2.7A uniquely combines field-programmable VTRIP, 400kHz I²C, and hardware-enforced Block Lock™ - delivering higher design flexibility, faster configuration access, and stronger data integrity assurance in resource-constrained embedded systems.

Availability

X4043P-2.2.7A is available at Aetrix Electronics and suitable for industrial PLC controllers, medical infusion pumps, automotive body control modules, smart energy meters, and battery-backed IoT edge nodes requiring stable component supply and long-term lifecycle support.

Supply support for X4043P-2.7A 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, now part of Renesas Electronics, designs high-performance analog and mixed-signal ICs for power management, precision sensing, and embedded control applications.

The X4043/X4045 family was developed to consolidate reset supervision, watchdog protection, and secure EEPROM into a single die - reducing board area and improving reliability in cost-sensitive microcontroller systems.

FAQ

What is the factory-programmed reset threshold voltage for X4043P-2.7A?

The X4043P-2.7A is factory-programmed with a reset threshold (VTRIP) of 2.85V to 3.0V, optimized for 3.3V system brownout detection. This value is stored in nonvolatile memory and remains stable over temperature and time. It can be reprogrammed to other values using a 15–18V pulse on the WP pin and an I²C command sequence, as detailed in the FN8118 datasheet. The X4043P-2.7A maintains this threshold accuracy without external components.

Does X4043P-2.7A support I²C Fast-mode (400kHz) operation?

Yes, the X4043P-2.7A fully supports I²C Fast-mode operation up to 400kHz. Its SDA and SCL pins meet standard I²C electrical specifications, including open-drain outputs and compatible timing parameters. The device acknowledges addresses and data correctly within Fast-mode timing windows, and its internal EEPROM write cycles do not interfere with bus arbitration. This allows high-speed configuration reads and writes in systems where rapid parameter access is critical - a capability not present in slower alternatives like the MAX6361KA29+T.

How does the watchdog timer in X4043P-2.7A differ from basic timeout-based watchdogs?

The X4043P-2.7A watchdog requires a full I²C protocol sequence - START, SCL LOW, SCL HIGH, STOP - to reset the timer, rather than simple SCL toggling. This prevents spurious clears caused by noise, partial bus transactions, or unintended SCL activity. The timeout period (200ms/600ms/1.4s) is set via nonvolatile WD1/WD0 bits and persists across power cycles. Unlike generic watchdog ICs, this design ensures only intentional, correctly formatted I²C activity resets the watchdog - enhancing system robustness in electrically noisy environments.

Can X4043P-2.7A's EEPROM be partially write-protected without using the WP pin?

Yes, the X4043P-2.7A supports hardware-level partial write protection independent of the WP pin via three nonvolatile Block Protect (BP2–BP0) bits. These bits configure eight protection modes - from locking just the first 16 bytes (page 1) to protecting the entire 512-byte array. Protection is enforced at the silicon level; writes to locked regions are silently ignored and generate no acknowledge. The WP pin provides global write disable, but BP bits allow granular, persistent protection ideal for safeguarding calibration data or boot code while permitting runtime logging in unlocked regions.

Is X4043P-2.7A pin-compatible with other members of the X4043/X4045 family?

Yes, all X4043 and X4045 variants - including X4043P-2.7A, X4043S8Z-2.7A, and X4043M8Z-2.7A - share identical 8-pin PDIP, SOIC, and MSOP pinouts and electrical characteristics. The only differences are reset polarity (X4043 = active-low RESET, X4045 = active-high RESET), VTRIP threshold, temperature grade, and package type. This allows direct substitution within the same package footprint, provided the reset polarity and thermal requirements match the target application. The X4043P-2.7A specifically uses PDIP packaging with active-low reset and 2.85–3.0V VTRIP.

X4043P-2.7A Specifications

Product attributes: Attribute value

Manufacturer:: Renesas

Series:: -

Package/Case:: 8-DIP (0.300", 7.62mm)

Packaging:: Tube

Product Status:: Obsolete

Programmable:: Not Verified

Type:: Simple Reset/Power-On Reset

Number of Voltages Monitored:: 1

Voltage - Threshold:: 2.92V

Output:: Open Drain or Open Collector

Reset:: Active Low

Reset Timeout:: 100ms Minimum

Operating Temperature:: 0°C ~ 70°C (TA)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: 8-PDIP

X4043P-2.7A FAQ

1.How can I place an order for X4043P-2.7A through Aetrix?

Please submit a Request for Quotation (RFQ) for X4043P-2.7A on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for X4043P-2.7A reliable?

The price and inventory of X4043P-2.7A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for X4043P-2.7A is usually 5 days.

3.What payment methods are accepted for X4043P-2.7A?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for X4043P-2.7A transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for X4043P-2.7A?

X4043P-2.7A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your X4043P-2.7A order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for X4043P-2.7A?

For technical support, including X4043P-2.7A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your X4043P-2.7A requirements.

6.How does Aetrix verify that X4043P-2.7A is sourced from the original manufacturer or authorized distributors?

All X4043P-2.7A products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that X4043P-2.7A meets industry standards.

7.What is the process for return or replacement of X4043P-2.7A?

All X4043P-2.7A units undergo pre-shipment inspection (PSI). If there is an issue with X4043P-2.7A, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The X4043P-2.7A part is unused and in its original packaging.

Return procedure for X4043P-2.7A:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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