Microchip Technology 24CW320T-E/Q4B66KVAO

Overview

24CW320T-E/Q4B66KVAO from Microchip Technology is a 32-Kbit I²C serial EEPROM organized as 4096 × 8-bit, supporting byte/page writes (up to 32 bytes), self-timed write cycles ≤5 ms, and operation across 1.6V–5.5V. It features programmable hardware client address bits (via HAR), software write protection (via WPR), and AEC-Q100 qualification for automotive use in infotainment control storage.

For engineers reviewing the 24CW320T-E/Q4B64KVAO datasheet, 24CW320T-E/Q4B66KVAO pinout, 24CW320T-E/Q4B66KVAO application, or 24CW320T-E/Q4B66KVAO equivalent, this page delivers verified electrical specs, I²C timing compliance (1 MHz max), package mapping to Q4B CSP, HAR/WPR configuration behavior, and automotive-grade reliability data including >1M write cycles and >200-year data retention.

Technical Context

The 24CW320T-E/Q4B66KVAO implements a two-wire I²C interface with Schmitt-trigger inputs and slope-controlled outputs to suppress noise and eliminate ground bounce. Its internal architecture includes dual configuration registers - Write Protection Register (WPR) for selective array write-locking and Hardware Address Register (HAR) for setting A2/A1/A0 address bits - both lockable to prevent runtime modification.

It supports up to eight devices on a shared bus via configurable 7-bit device addressing (1010xxxR/W), with memory access governed by word-address byte structure where bit 7 selects EEPROM vs. configuration register space. Power-on reset (VPOR ≤1.5 V) and tPUP ≥100 µs ensure deterministic initialization under 0.1 V/µs slew rate conditions.

Key Specifications

Pinout & Package

24CW320T-E/Q4B66KVAO uses the Q4B 4-ball CSP package (0.4 mm × 0.4 mm pitch, CS0 variant), with ball assignments matching the 4-Ball CSP (CS0) layout in DS20005772D. No-connect (NC) balls are present; active terminals are limited to SDA, SCL, VSS, and VCC.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C32D-SSHM-T and BR24G32FJ-3GE2, the 24CW320T-E/Q4B66KVAO uniquely combines AEC-Q100 Grade 0 qualification, HAR/WPR permanent lock, and full -40°C to +125°C operation - making it the only option qualified for safety-critical automotive EEPROM roles requiring guaranteed address isolation and immutable configuration.

Availability

24CW320T-E/Q4B66KVAO is available at Aetrix Electronics and suitable for automotive body control modules, industrial sensor calibration systems, medical infusion pump configuration storage, and smart meter firmware parameter retention requiring stable component supply across long product lifecycles.

Supply support for 24CW320T-E/Q4B66KVAO 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

Microchip Technology Inc. is a leading provider of microcontroller, analog, FPGA, and memory solutions, serving automotive, industrial, communications, and consumer markets with vertically integrated silicon and software platforms.

The 24CW Series was designed specifically for automotive and high-reliability industrial applications requiring robust I²C EEPROM with configurable addressing, software write protection, and extended temperature operation - directly addressing design needs in ECU parameter storage and sensor calibration.

FAQ

What is the exact memory organization of the 24CW320T-E/Q4B66KVAO?

The 24CW320T-E/Q4B66KVAO contains 32 Kbits of EEPROM organized as 4096 words × 8 bits, internally segmented into 128 pages of 32 bytes each. This structure enables efficient page-write operations within aligned 32-byte boundaries and supports byte-level random access using two-word addressing with MSb = 0 for EEPROM space.

Does the 24CW320T-E/Q4B66KVAO support 1 MHz I²C operation across its full voltage range?

Yes, the 24CW320T-E/Q4B66KVAO supports I²C clock frequencies up to 1 MHz for VCC = 1.6 V to 5.5 V, as specified in Table 1-2 (FCLK Max = 1000 kHz). This is enabled by slope-controlled outputs and Schmitt-trigger inputs, ensuring reliable timing margins even at 1.6 V supply.

How is hardware addressing configured on the 24CW320T-E/Q4B66KVAO?

Hardware addressing is set via the Hardware Address Register (HAR), which configures the A2/A1/A0 bits used in the 7-bit device address (1010xxxR/W). The preset address is encoded in the part number suffix '0'–'7'; for 24CW320T-E/Q4B66KVAO, the '0' indicates A2=A1=A0=0, yielding base address 0xA0 for write and 0xA1 for read.

Can the Write Protection Register (WPR) of the 24CW320T-E/Q4B66KVAO be permanently locked?

Yes, the WPR in the 24CW320T-E/Q4B66KVAO can be permanently locked to prevent further modification. Once locked, the write protection settings become immutable, ensuring that designated EEPROM regions (e.g., calibration data) remain protected against accidental or malicious overwrite throughout the device's operational life.

What package type does the 24CW320T-E/Q4B66KVAO use, and what are its key mechanical features?

The 24CW320T-E/Q4B66KVAO uses the Q4B 4-ball CSP package (CS0 variant), measuring 0.4 mm × 0.4 mm with 0.4 mm pitch. It has no exposed thermal pad and places VCC, VSS, SDA, and SCL on four corners - enabling ultra-compact placement in space-constrained automotive modules while maintaining signal integrity via short interconnects.