Renesas X5045P-2.7A

Overview

X5045P-2.7A from Intersil (now Renesas) is a 4K-bit SPI EEPROM with integrated CPU supervisor functions including power-on reset, watchdog timer, and programmable voltage monitoring. It operates from 2.7V to 5.5V, features a 2.85–3.0V reset threshold, 3.3MHz SPI interface, and block-lock memory protection-used in industrial controllers and network equipment for reliable system initialization and data retention.

For engineers reviewing the X5045P-2.7A datasheet, X5045P-2.7A pinout, X5045P-2.7A application, or X5045P-2.7A equivalent, key selection criteria include its active-high RESET output, 8-pin PDIP package, 200ms reset timeout, 1M write-cycle endurance, and reprogrammable VTRIP capability for precision brownout detection.

Technical Context

The X5045P-2.7A integrates four independent functional blocks: a POR circuit that asserts RESET for ≥200ms after VCC exceeds 2.85V; a watchdog timer with three selectable timeouts (200ms/600ms/1.4s) controlled by nonvolatile WD0/WD1 bits; a low-voltage detector with factory-set 2.93V ±2.5% trip point (reprogrammable via VP=15–18V sequence); and a 512×8-bit SPI EEPROM with Direct Write™ cells enabling 1M write cycles and 100-year data retention.

Its CS/WDI pin serves dual roles: chip select for SPI commands and watchdog input requiring periodic toggling; WP enables hardware write protection; SO/SI/SCK implement full-duplex SPI at up to 3.3MHz; and RESET remains valid down to VCC = 1V with open-drain output configuration compatible with 3.3V/5V systems.

Key Specifications

Pinout & Package

Package: 8-lead PDIP (Plastic Dual In-line Package), Pb-free plus anneal RoHS-compliant, 0°C to +70°C operating temperature range.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MCP9800T-E/MS and MAX6361KA29+T, the X5045P-2.7A uniquely combines voltage supervision, watchdog timer, and 4K-bit SPI EEPROM in one 8-pin PDIP package-reducing BOM count, PCB area, and qualification effort versus discrete solutions.

Availability

X5045P-2.7A is available at Aetrix Electronics and suitable for industrial process controllers, network infrastructure equipment, battery-powered telemetry nodes, and medical diagnostic instruments requiring stable component supply and long-term lifecycle support.

Supply support for X5045P-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 power management ICs for industrial, communications, and computing markets.

The X5045P-2.7A belongs to Intersil's CPU Supervisor family, engineered to consolidate power monitoring, reset generation, watchdog protection, and nonvolatile storage into a single SPI-compatible device for space-constrained embedded systems.

FAQ

What is the reset polarity and output type of the X5045P-2.7A?

The X5045P-2.7A features an active-high RESET output implemented as an open-drain driver. This requires an external pull-up resistor to VCC to establish a defined logic-high level. The signal asserts when VCC falls below 2.85V or during power-up until VCC stabilizes for 200ms, and also activates upon watchdog timeout. Its open-drain structure allows wired-OR configurations with other reset sources in complex systems.

How does the X5045P-2.7A's watchdog timer operate and how is its timeout configured?

The X5045P-2.7A watchdog timer monitors the CS/WDI pin and triggers RESET if no falling edge occurs within the selected interval. Timeout is set via nonvolatile WD0/WD1 bits in the status register: 00 = 1.4s, 01 = 600ms, 10 = 200ms, 11 = disabled. These bits retain their value across power cycles, eliminating need for reinitialization after reboot. The X5045P-2.7A requires only a CS toggle-not dedicated WDI pin-to reset the timer.

Can the voltage reset threshold (VTRIP) of the X5045P-2.7A be modified, and what is required?

Yes, the X5045P-2.7A's VTRIP can be reprogrammed to custom values using a 15–18V programming voltage (VP) applied to the WP pin. The procedure requires applying the target VTRIP voltage to VCC, issuing WREN followed by writing 00h to address 01h, then bringing WP low. This modifies the internal reference without affecting EEPROM data. Factory default is 2.93V ±2.5%; the X5045P-2.7A supports upward adjustment only-downward changes require a reset sequence first.

What memory protection mechanisms does the X5045P-2.7A provide for its 4K-bit EEPROM?

The X5045P-2.7A implements three-tiered EEPROM protection: (1) hardware WP pin disables all writes when low; (2) software-controlled Write Enable Latch (WEL) must be set before any write command; (3) nonvolatile Block Lock™ bits (BL0/BL1) permanently protect 0%, 25%, 50%, or 100% of the 512×8 array. These layers ensure critical calibration data or boot code remains intact during firmware updates or electrical transients-making the X5045P-2.7A suitable for safety-critical applications.

What is the maximum SPI clock frequency supported by the X5045P-2.7A, and how does it affect write performance?

The X5045P-2.7A supports SPI clock frequencies up to 3.3MHz across its full 2.7–5.5V supply range. At this rate, a 16-byte page write completes in ≤5ms typical, enabling rapid configuration updates. The device uses MSB-first transmission with setup/hold times compliant to standard SPI masters. Unlike slower legacy supervisors, the X5045P-2.7A's 3.3MHz interface eliminates bottlenecks in high-throughput systems-such as routers reloading QoS tables or medical devices validating calibration checksums.