M93C86, M93C76, M93C66, M93C56, M93C46, M93C06
cle, a Busy/Ready signal is available on Serial
Data Output (Q) when Chip Select Input (S) is driv-
An internal Power-on Data Protection mechanism
in the M93Cx6 inhibits the device when the supply
is too low.
Figure 3. DIP, SO and TSSOP Connections
Note: 1. See page 21 (onwards) for package dimensions, and how
to identify pin-1.
2. DU = Don’t Use.
Figure 4. 90° Turned-SO Connections
Note: 1. See page 24 for package dimensions, and how to identify
2. DU = Don’t Use.
The DU (Don’t Use) pin does not contribute to the
normal operation of the device. It is reserved for
use by STMicroelectronics during test sequences.
The pin may be left unconnected or may be con-
nected to VCC or VSS. Direct connection of DU to
VSS is recommended for the lowest stand-by pow-
The M93Cx6 memory is organized either as bytes
(x8) or as words (x16). If Organization Select
(ORG) is left unconnected (or connected to VCC)
the x16 organization is selected; when Organiza-
tion Select (ORG) is connected to Ground (VSS)
the x8 organization is selected. When the M93Cx6
is in stand-by mode, Organization Select (ORG)
should be set either to VSS or VCC for minimum
power consumption. Any voltage between VSS
and VCC applied to Organization Select (ORG)
may increase the stand-by current.
POWER-ON DATA PROTECTION
To prevent data corruption and inadvertent write
operations during power-up, a Power-On Reset
(POR) circuit resets all internal programming cir-
cuitry, and sets the device in the Write Disable
– At Power-up and Power-down, the device must
not be selected (that is, Chip Select Input (S)
must be driven Low) until the supply voltage
reaches the operating value VCC specified in
Table 8 to Table 10.
– When VCC reaches its valid level, the device is
properly reset (in the Write Disable mode) and
is ready to decode and execute incoming in-
For the M93Cx6 devices (5V range) the POR
threshold voltage is around 3V. For the M93Cx6-
W (3V range) and M93Cx6-R (2V range) the POR
threshold voltage is around 1.5V.