Spark Logic

24C64 EEPROM (24LC64) pinout

The 24LC64 is a 64-Kbit I²C EEPROM that stores 8 KiB and writes up to 32 bytes per page.

PDIP-8 8 contacts
SOIC-8 8 contacts
SOIJ-8 8 contacts
MSOP-8 8 contacts
TSSOP-8 8 contacts
X-rotated TSSOP-8 8 contacts
DFN-8 9 contacts
TDFN-8 9 contacts

SOT-23-5

5 contacts Current package

Microchip Technology · Five leads · 0.95 mm lead pitch · Microchip package code /OT

SOT-23-5 pinout

SOT-23-5
Top view · Locate pin 1 using the package index mark. Scroll the map to reach all contacts.
Selected pin details

1 · SCL

Input · Clock inputs / oscillator

Serial clock from the host. On an open-drain bus, provide a pull-up to the bus rail.

DS20001189V · §2 and Table 2-1

Electrical limits · Link to this pin

All 5 pins

PinSignalDirectionFunction
1SCL InputInput Serial clock from the host. On an open-drain bus, provide a pull-up to the bus rail.
2VSS ReferenceReference Supply return and signal reference. Connect to the host ground.
3SDA Open-drain I/OOpen-drain I/O Serial address and data. Pull up to the bus rail and let the host and EEPROM drive only LOW.
4VCC SupplySupply Regulated 2.5–5.5 V supply. Bypass locally to VSS.
5WP InputInput Tie to VCC to protect the entire array or to VSS to enable writes. Reads are available in both states.

Signal assignments

I²C bus

Use 7-bit address 0x50. The SOT-23-5 version has no external chip-select pins, so the three select bits must be zero.

Send two memory-address bytes, high byte first. The usable offset ends at 0x1FFF.

Write protection

Tie to VCC to protect the entire array or to VSS to enable writes. Reads are available in both states.

Electrical limits

ParameterLimitConditions and source
Operating supply2.5–5.5 V2.5–5.5 V Industrial (I) and extended (E) temperature ranges are listed in the device selection table. Check the exact order code. DS20001189V · p. 1
I²C clock limit400 kHz400 kHz Meet the AC timing, voltage and pull-up requirements. The wiring example uses 100 kHz. DS20001189V · §1, Table 1-2
Input thresholdsLOW ≤ 0.3 × VCC · HIGH ≥ 0.7 × VCCLOW ≤ 0.3 × VCC · HIGH ≥ 0.7 × VCC Relative to VSS over the specified supply range. Use a common-voltage bus or level shifting. DS20001189V · §1, Table 1-1
SDA output LOW≤ 0.40 V≤ 0.40 V Specified at 2.1 mA sink current with VCC = 2.5 V and at 3.0 mA with VCC = 4.5 V. DS20001189V · §1, Table 1-1
Memory and word address8 KiB · 2 address bytes8 KiB · 2 address bytes Offsets 0x0000–0x1FFF. Client and memory addressing are described in the I²C signal assignment. DS20001189V · p. 1 and §5
Page write32 bytes · 5 ms maximum write cycle32 bytes · 5 ms maximum write cycle Split writes at page boundaries and use acknowledge polling after STOP. Read explicitly addressed data after power-up. DS20001189V · Table 1-2 and §§6–8

Models and documents

This reference covers the standard package codes listed for Microchip 24LC64 and the 24LC64X pin assignment in the linked datasheet. Match the full manufacturer part number before wiring a device marked 24C64. Use its own datasheet for other manufacturers or the Microchip AA and FC versions. The five-ball Chip Scale package is an industrial 24AA64 option, and the DFN-S package is listed for 24FC64.

24LC64
The /OT package suffix selects this outline. Check the ordering table for supported temperature and reel combinations.