Active Power, Stand-by Power
The Hold condition starts on the falling edge of the Hold
(HOLD) signal, provided that this coincides with Serial
When Chip Select (S#) is Low, the device is enabled, and Clock (C) being Low (as shown in Figure 3).
in the Active Power mode. When Chip Select (S#) is High,
the device is disabled, but could remain in the Active The Hold condition ends on the rising edge of the Hold
Power mode until all internal cycles have completed. The (HOLD#) signal, provided that this coincides with Serial
device then goes in to the Stand-by Power mode. The Clock (C) being Low.
device consumption drops to ICC1 .
If the falling edge does not coincide with Serial Clock (C)
being Low, the Hold condition starts after Serial Clock (C)
next goes Low. Similarly, if the rising edge does not
The environments where non-volatile memory devices are coincide with Serial Clock (C) being Low, the Hold condi-
used can be very noisy. No SPI device can operate tion ends after Serial Clock (C) next goes Low. (This is
correctly in the presence of excessive noise. To help shown in Figure 2).
combat this, the MX23L12854 boasts the following data
During the Hold condition, the Serial Data Output (Q) is
high impedance, and Serial Data Input (D) and Serial Clock
- Power-On Reset and an internal timer (tPUW) can provide (C) are Don't Care.
protection against inadvertant changes while the power
supply is outside the operating specification.
Normally, the device is kept selected, with Chip Select
driven Low, for the whole duration of the Hold condi-
This is to ensure that the state of the internal logic
DataSheet4Urc.ecomonmdaiitniosnu.nchanged from the moment of entering the Hold
The Hold (HOLD#) signal is used to pause any serial
communications with the device without resetting the
To enter the Hold condition, the device must be selected,
with Chip Select (S#) Low.
If Chip Select (S#) goes High while the device is in the Hold
condition, this has the effect of resetting the internal logic
of the device. To restart communication with the device,
it is necessary to drive Hold (HOLD#) High, and then to
drive Chip Select (S#) Low. This prevents the device from
going back to the Hold condition.
Figure 3. Hold Condition Activation (for data output only)
DataSheet4 U .com
REV. 1.1, MAY. 04, 2005