Document
M24256-BW M24256-BR M24256-BF M24256-DR M24256-DF
Datasheet
256-Kbit serial I²C bus EEPROM
TSSOP8 (DW) 169 mil width
SO8N (MN) 150 mil width
UFDFPN8 (MC) DFN8 - 2x3 mm
WLSCP (CU)
WLSCP (CS)
Unsawn wafer Product status link
M24256-BF M24256-DF M24256-BR M24256-DR M24256-BW
Features
• Compatible with following I2C bus modes: – 1 MHz – 400 kHz – 100 kHz
• Memory array: – 256 Kbit (32 Kbyte) of EEPROM – Page size: 64 byte – Additional write lockable page (M24256-D order codes)
• Single supply voltage and high speed: – 1 MHz clock from 1.7 V to 5.5 V
• Write: – Byte write within 5 ms – Page write within 5 ms
• Operating temperature range: – from -40 °C up to +85 °C
• Random and sequential read modes • Write protect of the whole memory array • Enhanced ESD/latch-Up protection • More than 4 million write cycles • More than 200-years data retention
Packages
• RoHS-compliant and Halogen-free (ECOPACK2) • SO8 ECOPACK2 • TSSOP8 ECOPACK2 • UFDFPN8 ECOPACK2 • WLCSP ECOPACK2 • Unsawn wafer (each die is tested)
DS1766 - Rev 35 - November 2020 For further information contact your local STMicroelectronics sales office.
www.st.com
M24256-BW M24256-BR M24256-BF M24256-DR M24256-DF
Description
1
Description
The M24256 is a 256-Kbit I2C-compatible EEPROM (electrically erasable programmable memory) organized as 32 K × 8 bits. The M24256-BW can operate with a supply voltage from 2.5 V to 5.5 V, the M24256-BR AND M24256-DR can operate with a supply voltage from 1.8 V to 5.5 V, and the M24256-BF and M24256-DF can operate with a supply voltage from 1.7 V to 5.5 V. All these devices operate with a clock frequency of 1 MHz (or less), over an ambient temperature range of –40 °C / +85 °C. The M24256-D offers an additional page, named the identification page (64 byte). The identification page can be used to store sensitive application parameters which can be (later) permanently locked in read-only mode.
Figure 1. Logic diagram
VCC
3 E0-E2
SCL WC
M24xxx
SDA
VSS
E2, E1, E0 SDA SCL WC VCC VSS
Signal name
Table 1. Signal names
Chip enable Serial data Serial clock Write control Supply voltage
Function
Ground
Input I/O Input Input -
Direction
Figure 2. 8-pin package connections, top view
E0 1 E1 2 E2 3 VSS 4
8 VCC 7 WC 6 SCL 5 SDA
1. See Section 9 Package information for package dimensions, and how to identify pin 1
DS1766 - Rev 35
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M24256-BW M24256-BR M24256-BF M24256-DR M24256-DF
Description
Figure 3. WLCSP connections
1
2
3
A
WC
E1
B
E0
C
VCC
VSS
D
SDA
E
SCL
E2
Marking side (top view)
3
2
1
E1
WC
A
E0
B
VSS
VCC
C
SDA
D
E2
SCL
E
Bump side (bottom view)
Table 2. Signal vs. bump position
Position
A
B
C
D
E
1
WC
-
VCC
-
SCL
2
-
E0
-
SDA
-
3
E1
-
VSS
-
E2
DS1766 - Rev 35
page 3/47
M24256-BW M24256-BR M24256-BF M24256-DR M24256-DF
Signal description
2
Signal description
2.1
Serial clock (SCL)
The signal applied on the SCL input is used to strobe the data available on SDA(in) and .