M95256-WMW6TG STMicroelectronics, M95256-WMW6TG Datasheet - Page 26

• Manufacturer Part Number: M95256-WMW6TG
• Description: IC EEPROM 256KBIT 5MHZ 8SOIC
• Manufacturer: STMicroelectronics

Specifications of M95256-WMW6TG

• Format - Memory: EEPROMs - Serial
• Memory Type: EEPROM
• Memory Size: 256K (32K x 8)
• Speed: 5MHz
• Interface: SPI, 3-Wire Serial
• Voltage - Supply: 2.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-SOIC (5.3mm Width), 8-SOP, 8-SOEIAJ
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-8692-2; M95256-WMW6TG

Delivery state
6
7
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Delivery state
The device is delivered with the memory array set at all 1s (FFh). The Status Register Write
Disable (SRWD) and Block Protect (BP1 and BP0) bits are initialized to 0.
Connecting to the SPI bus
These devices are fully compatible with the SPI protocol.
All instructions, addresses and input data bytes are shifted in to the device, most significant
bit first. The Serial Data input (D) is sampled on the first rising edge of the Serial Clock (C)
after Chip Select (S) goes low.
All output data bytes are shifted out of the device, most significant bit first. The Serial Data
output (Q) is latched on the first falling edge of the Serial Clock (C) after the instruction (such
as the Read from Memory Array and Read Status Register instructions) have been clocked
into the device.
Figure 17
bus. Only one memory device is selected at a time, so only one memory device drives the
Serial Data output (Q) line at a time, the other memory devices are high impedance.
Figure 17. Bus master and memory devices on the SPI bus
1. The Write Protect (W) and Hold (HOLD) signals should be driven, high or low as appropriate.
A pull-up resistor connected on each /S input (represented in
slave device on the SPI bus is not selected if the bus master leaves the /S line in the high
impedance state.
CS3
SPI Interface with
(ST6, ST7, ST9,
(CPOL, CPHA) =
ST10, Others)
(0, 0) or (1, 1)
Bus Master
CS2 CS1
shows an example of three memory devices connected to an MCU, on an SPI
SDO
SDI
SCK
R
R
Doc ID 12276 Rev 13
C Q D
S
SPI Memory
Device
W
V
CC
HOLD
V
M95256-DR, M95256, M95256-W, M95256-R
SS
R
C Q D
S
SPI Memory
Device
W
V
Figure
CC
HOLD
V
SS
R
7) ensures that each
C Q D
S
SPI Memory
Device
W
V
CC
HOLD
AI12304b
V
V
V
SS
CC
SS