The M95010/ M95020/M95040 devices (M950x0) are electrically erasable programmable memories (EEPROMs) organized as 128/256/512 x 8 bits respectively, accessed through the SPI bus.The M950x0-W can operate with a supply voltage from 2.5 V to 5.5 V, the M950x0-R can operate with a supply voltage from 1.8 V to 5.5 V, and the M950x0-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 M950x0-DF offers an additional page, named the Identification Page (16 bytes). The Identification Page can be used to store sensitive application parameters which can be (later) permanently locked in Read-only mode.Compatible with SPI bus serial interface (Positive clock SPI modes)Single supply voltage:2.5 V to 5.5 V for M950x0-W1.8 V to 5.5 V for M950x0-R1.7 V to 5.5 V for M95040-DFHigh-speed 20 MHz clock rate, 5 ms write timeMemory array:1/2/4 Kbit (128/256/512 bytes) of EEPROMPage size: 16 bytesWrite protection by block: 1/4, 1/2 or whole memoryAdditional Write lockable Page (Identification page)Enhanced ESD protectionMore than 4 million write cyclesMore than 200-year data retentionPackages RoHS-compliant and Halogen-free (ECOPACK®)