NXP Semiconductors PCA24S08D/DG,118

Overview

The PCA24S08D/DG,118 from NXP Semiconductors is a 1024 × 8-bit (8 kbit) I²C-compatible serial EEPROM with hardware-based access protection, organized into eight 128-byte blocks and supporting byte/page write modes (up to 16 bytes), 2.5–3.6 V operation, and 400 kHz I²C clock frequency. It is used in embedded systems requiring secure non-volatile parameter storage, such as industrial controllers and automotive ECUs.

For engineers reviewing the PCA24S08D/DG,118 datasheet, PCA24S08D/DG,118 pinout, PCA24S08D/DG,118 application, or PCA24S08D/DG,118 equivalent, key selection criteria include its programmable block- and page-level read/write protection, WP and PROT pin control logic, SO8 package compatibility, and 100,000-cycle endurance with 10-year data retention.

Technical Context

The PCA24S08D/DG,118 implements an I²C-bus interface with slave address range A8h–AFh (write) and B8h/B9h for protected Access Protection Page (APP) and ID Page access. Its internal architecture includes an 8-block EEPROM array (128 bytes/block), dedicated APP memory (16 bytes), and ID page (16 bytes), all accessed via two-byte addressing with MSB-first transmission.

Protection is enforced via sticky bits (SB0–SB7, SBAP), protection bits (PB0–PB7, PBAP), and WPN bits for Block 0 page-level write control. The PROT pin resets the serial interface and sets all sticky bits high when pulled low; WP pin enables full-array write protection when high.

Key Specifications

Pinout & Package

PCA24S08D/DG,118 is supplied in SO8 (SOT96-1) package: plastic small outline, 8 leads, 3.9 mm body width, standard 1.27 mm lead pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar serial EEPROM applications.

Compared with AT24C08D-SSHM-T and ST M24C08-RMN6TP/K, the PCA24S08D/DG,118 delivers unique hardware-enforced memory segmentation and tamper-resilient identity storage-critical for safety-critical or regulated applications where software-only protection is insufficient.

Availability

PCA24S08D/DG,118 is available at Aetrix Electronics and suitable for industrial sensor calibration, automotive ECU configuration, medical device settings backup, and POS terminal security keys requiring stable component supply and long-term lifecycle support.

Supply support for PCA24S08D/DG,118 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

NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT applications.

The PCA24S08D/DG,118 belongs to NXP's serial EEPROM product line, designed specifically for systems demanding hardware-enforced memory access control, secure identity storage, and robust operation across extended temperature ranges.

FAQ

What is the primary function of the PROT pin on the PCA24S08D/DG,118?

The PROT pin on the PCA24S08D/DG,118 is an active-low reset and initialization input. When held LOW, it forces the serial interface into reset state and sets all sticky bits (SB0–SB7, SBAP) to logic 1-enabling subsequent reprogramming of protection bits. This ensures deterministic startup behavior and secure reconfiguration of access permissions. The PCA24S08D/DG,118 requires this signal to be released HIGH before normal I²C communication can resume.

How does the PCA24S08D/DG,118 differ from standard 24C08 EEPROMs in pin usage?

The PCA24S08D/DG,118 differs from standard 24C08 devices in Pins 1, 2, and 3: Pins 1 and 2 are no-connect (n.c.), while Pin 3 is the active-low PROT input-not address pins as in 24C08. This eliminates external address jumpers but adds hardware reset and sticky-bit control. All other pins (VSS, SDA, SCL, WP, VDD) retain identical functions and electrical characteristics, ensuring mechanical compatibility in SO8 layouts.

Can the PCA24S08D/DG,118 perform multi-byte reads across block boundaries?

No, the PCA24S08D/DG,118 does not allow multi-byte reads to cross block boundaries. Upon reaching the last byte of a 128-byte block during sequential read, the internal address counter wraps to the first byte of that same block-not the next block. This behavior is explicitly defined in Section 6.6 as a functional exception versus standard 24C08 devices and ensures memory access remains confined within configured protection domains.

What happens if more than 16 bytes are transmitted during a page write to the PCA24S08D/DG,118?

If more than 16 bytes are sent before the STOP condition in a page write sequence, the PCA24S08D/DG,118 will not acknowledge the 17th and subsequent bytes, and the entire transmission is ignored-no programming occurs. This prevents unintended data corruption due to bus master timing errors. The device remains responsive to new commands immediately after the invalid sequence, with no internal write cycle initiated.

Is the ID page of the PCA24S08D/DG,118 writable after initial programming?

The ID page (accessed via B9h address) of the PCA24S08D/DG,118 is writable only when PBAP = 11b and SBAP = 1. Once SBAP is cleared to 0, the ID page becomes permanently read-only for that power cycle. The device revision byte (address 15) is factory-programmed to 10h and cannot be altered in the field-even if PBAP and SBAP permit writes, attempts to modify it are acknowledged but ignored.