M93C86, M93C76, M93C66, M93C56, M93C46
Supply voltage (VCC)
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).
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.
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)
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).