Operating features M95160-x, M95080-x
12/49 Doc ID 8028 Rev 11
4 Operating features
4.1 Supply voltage (V
CC
)
4.1.1 Operating supply voltage V
CC
Prior to selecting the memory and issuing instructions to it, a valid and stable V
CC
voltage
within the specified [V
CC
(min), V
CC
(max)] range must be applied (see Ta ble 9, Ta bl e 10 and
Tabl e 1 1 ). 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 (t
W
). In
order to secure a stable DC supply voltage, it is recommended to decouple the V
CC
line with
a suitable capacitor (usually of the order of 10 nF to 100 nF) close to the V
CC
/V
SS
package
pins.
4.1.2 Device reset
In order to prevent inadvertent write operations during power-up, a power-on-reset (POR)
circuit is included. At power-up, the device does not respond to any instruction until V
CC
reaches the POR threshold voltage (this threshold is defined in DC characteristics tables 15,
16, 17, 18, 19 and 20 as V
RES
).
When V
CC
passes over the POR threshold, the device is reset and is in the following state:
● in Standby Power mode
● deselected (note that, to be executed, an instruction must be preceded by a falling
edge on Chip Select (S
))
● Status Register value:
– the Write Enable Latch (WEL) is reset to 0
– Write In Progress (WIP) is reset to 0
– The SRWD, BP1 and BP0 bits remain unchanged (non-volatile bits)
When V
CC
passes over the POR threshold, the device is reset and enters the Standby
Power mode. The device must not be accessed until V
CC
reaches a valid and stable V
CC
voltage within the specified [V
CC
(min), V
CC
(max)] range defined in Ta ble 9, Ta bl e 10 and
Tabl e 1 1 .
4.1.3 Power-up conditions
When the power supply is turned on, V
CC
rises continuously from V
SS
to V
CC
. During this
time, the Chip Select (S
) line is not allowed to float but should follow the V
CC
voltage. It is
therefore recommended to connect the S
line to V
CC
via a suitable pull-up resistor (see
Figure 4).
In addition, the Chip Select (S
) input offers a built-in safety feature, as the S input is edge
sensitive as well as level sensitive: after power-up, the device does not become selected
until a falling edge has first been detected on Chip Select (S
). This ensures that Chip Select
(S
) must have been high, prior to going low to start the first operation.
The V
CC
voltage has to rise continuously from 0 V up to the minimum V
CC
operating voltage
defined in Tabl e 9 , Table 1 0 and Ta ble 1 1 and the rise time must not vary faster than 1 V/µs.
