Microchip Technology 24LC04BT-E/SN

Overview

24LC04BT-E/SN from Microchip Technology Inc. is a 4-Kbit I²C-compatible serial EEPROM organized as two 256 × 8-bit blocks, operating from 2.5V to 5.5V with 400 kHz max clock frequency, 5 ms max page write time, and industrial/extended temperature support (–40°C to +125°C). It delivers low-power operation (1 µA standby, 1 mA read), hardware write-protection via WP pin, and 1 million erase/write cycles for embedded configuration storage in microcontroller systems.

For engineers reviewing the 24LC04BT-E/SN datasheet, 24LC04BT-E/SN pinout, 24LC04BT-E/SN application, or 24LC04BT-E/SN equivalent, key selection considerations include its SOIC-8 narrow package, I²C address structure (1010xxxR/W), page write buffer (16 bytes), Schmitt-trigger inputs for noise immunity, and extended-temp qualification per AEC-Q100 for automotive and industrial deployments.

Technical Context

The 24LC04BT-E/SN implements a two-wire I²C interface with fixed 4-bit control code (1010) and block-select bit (B0), enabling access to either 256-byte memory block. Its internal Address Pointer auto-increments during sequential reads and supports current-address, random, and sequential read modes.

Write operations use acknowledge polling to detect completion of self-timed 5 ms erase/write cycles. The device features Schmitt-trigger inputs and output slope control to suppress bus noise and eliminate ground bounce - critical for reliable operation in electrically noisy environments such as automotive body control modules and industrial sensor nodes.

Key Specifications

Pinout & Package

24LC04BT-E/SN uses an 8-lead plastic small outline (SOIC-N) package, 3.90 mm body width, with gull-wing leads and JEDEC-standard pinout. Pin 1 is top-left corner (notch-marked side).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC04BT-E/SN, the 24AA04T-I/SN trades extended temperature for ultra-low-voltage operation, while the 24FC04T-E/SN adds 1 MHz I²C speed at identical voltage and package - both retain the same 16-byte page buffer and WP functionality but require revalidation of timing margins and thermal derating.

Availability

24LC04BT-E/SN is available at Aetrix Electronics and suitable for automotive body control units, industrial PLCs, medical infusion pumps, and smart energy meters requiring stable component supply with guaranteed long-term availability and traceable sourcing.

Supply support for 24LC04BT-E/SN 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 microcontrollers, analog devices, and memory solutions, headquartered in Chandler, Arizona, with global manufacturing and support infrastructure.

The 24LC04B series belongs to Microchip's serial EEPROM product line, designed specifically for reliable, low-power, I²C-based nonvolatile storage in automotive, industrial, and medical applications demanding extended temperature operation and AEC-Q100 compliance.

FAQ

What is the exact memory organization of the 24LC04BT-E/SN?

The 24LC04BT-E/SN contains 4 Kbit (512 bytes) of EEPROM memory, organized as two independent blocks of 256 × 8-bit locations (000h–0FFh and 100h–1FFh). Block selection is controlled by bit B0 in the I²C control byte, allowing discrete access to each 256-byte segment without overlap or aliasing. This structure is explicitly defined in the device addressing section of the DS20001708P datasheet.

Does the 24LC04BT-E/SN support standard I²C addressing with A0/A1/A2 pins?

No - the 24LC04BT-E/SN does not use A0, A1, or A2 pins for device addressing. As confirmed in Section 2.1 and Table 2-1 of DS20001708P, these pins are unconnected internally. The device responds only to the fixed 4-bit control code '1010', with the fifth bit (B0) selecting memory block and the LSB indicating R/W mode - resulting in only two possible I²C addresses: 0xA0 (write) and 0xA1 (read) for block 0, or 0xA4/0xA5 for block 1.

What is the purpose of the WP pin on the 24LC04BT-E/SN, and how must it be connected?

The WP (Write-Protect) pin on the 24LC04BT-E/SN is an active-high hardware lock that disables all write operations (byte and page) when pulled to VCC. When tied to VSS (or left floating, though not recommended), full read/write access is enabled. This function is documented in Section 2.4 and Figure 6-1 of DS20001708P and provides fail-safe protection against unintended memory corruption during power-up/down or software errors.

Can the 24LC04BT-E/SN operate at 1.8V supply voltage?

No - the 24LC04BT-E/SN has a minimum VCC specification of 2.5V, as stated in the Device Selection Table on page 2 of DS20001708P. Attempting operation below 2.5V violates absolute maximum ratings and risks unreliable read/write behavior, failed acknowledge polling, or incomplete write cycles. For 1.7V–1.8V operation, the 24AA04T-I/SN variant is specified and validated.

How does the 24LC04BT-E/SN handle page boundary crossing during a page write?

The 24LC04BT-E/SN wraps page write data back to the start of the current 16-byte physical page if the write crosses a boundary - e.g., writing 16 bytes starting at address 0x0F fills 0x0F–0x1E, then overwrites 0x10–0x1F. This wraparound behavior is explicitly described in Figure 6-2 and the note under Section 6.2 of DS20001708P. Application firmware must enforce page-aligned writes or limit transfers to ≤16 bytes within a single page (0x00–0x0F, 0x10–0x1F, etc.) to avoid data loss.