M93C86 datasheet(10/37 Pages) STMICROELECTRONICS

10 / 37 page

Operating features

M93C86, M93C76, M93C66, M93C56, M93C46

10/37

Doc ID 4997 Rev 10

Operating features

3.1

Supply voltage (VCC)

3.1.1

Operating supply voltage VCC

Prior to selecting the memory and issuing instructions to it, a valid and stable VCC voltage

within the specified [VCC(min), VCC(max)] range must be applied. In order to secure a stable

DC supply voltage, it is recommended to decouple the VCC line with a suitable capacitor

(usually of the order of 10 nF to 100 nF) close to the VCC/VSS package pins.

This voltage must remain stable and valid until the end of the transmission of the instruction

and, for a Write instruction, until the completion of the internal write cycle (tW).

3.1.2

Power-up conditions

When the power supply is turned on, VCC rises from VSS to VCC. During this time, the Chip

Select (S) line is not allowed to float and should be driven to VSS, it is therefore

recommended to connect the S line to VSS via a suitable pull-down resistor.

The VCC rise time must not vary faster than 1 V/µs.

3.1.3

Power-up and device reset

In order to prevent inadvertent Write operations during power-up, a power on reset (POR)

circuit is included. At power-up (continuous rise of VCC), the device does not respond to any

instruction until VCC has reached the power on reset threshold voltage (this threshold is

lower than the minimum VCC operating voltage defined in Table 9, Table 10 and Table 11).

When VCC passes the POR threshold, the device is reset and is in the following state:

●

Standby Power mode

●

deselected (assuming that there is a pull-down resistor on the S line)

3.1.4

Power-down

At power-down (continuous decrease in VCC), as soon as VCC drops from the normal

operating voltage to below the power on reset threshold voltage, the device stops

responding to any instruction sent to it.

During power-down, the device must be deselected and in the Standby Power mode (that is,

there should be no internal Write cycle in progress).

M93C86 데이터시트(PDF) 10 Page - STMicroelectronics