M95256-R datasheet(2/51 Pages) STMICROELECTRONICS

2 / 51 page

Description

The M95256 devices are electrically erasable programmable memories (EEPROMs) organized as 32768 x 8 bits,

accessed through the SPI bus.

The M95256-W can operate with a supply voltage from 2.5 V to 5.5 V, the M95256-R can operate with a supply

voltage from 1.8 V to 5.5 V and the M95256-DF can operate with a supply voltage from 1.7 V to 5.5 V, over an

ambient temperature range of -40 °C / +85 °C.

The M95256-DF, -DR or -DW (hereinafter referred to as M95256-Dx) offer an additional page, named the

Identification page (64 bytes). The Identification page can be used to store sensitive application parameters

that can be (later) permanently locked in read-only mode.

Figure 1. Logic diagram

VCC

HOLD

M95xxx

VSS

The SPI bus signals are C, D and Q, as shown in Figure 1 and Table 1. The device is selected when Chip select

(S) is driven low. Communications with the device can be interrupted when the HOLD is driven low.

Table 1. Signal names

Signal name

Function

Direction

Serial clock

Input

Serial data input

Input

Serial data output

Output

Chip select

Input

Write protect

Input

HOLD

Hold

Input

VCC

Supply voltage

VSS

Ground

M95256-W M95256-R M95256-DF

Description

DS4712 - Rev 22

page 2/51

M95256-R Datasheet(PDF) 2 Page - STMicroelectronics