TH50VSF3680 Datasheet, PDF (36/55 Pages) Toshiba Semiconductor – SRAM AND FLASH MEMORY MIXED MULTI-CHIP PACKAGE

DATA PROTECTION
TH50VSF3680/3681AASB
The TH50VSF3680/3681AASB features a function which makes malfunction or data damage difficult.
Protection Against Program/Erase Caused by Low Supply Voltage
To prevent malfunction at power on or power down, the device does not receive commands when VCCf is below
VLKO. In this state, command input is ignored.
If VCCf drops below VLKO during Auto operations, the device terminates Auto Program execution. In this case,
Auto operation is not executed again when VCCf return to recommended VCCf voltage Therefore, command need
to be input to execute Auto operation again.
When VCCf > VLKO, make up countermeasure to be input accurately command in system side please.
Protection Against Malfunction Caused by Glitches
To prevent malfunction caused by noise from the system in operation, the device does not receive pulses
shorter than 3 ns(Typ.) input to WE , CEF , or OE . However, if a glitch exceeding 3 ns(Typ.) occurs and the
glitch is input to the device, although rare, malfunction may occur.
The device uses standard JEDEC commands; thus making command input difficult. It is conceivable that in an
extreme case a part of a command sequence input due to system noise may occur. At this time, the device
acknowledges the part of the command sequence. Then, even if the proper command is input, the device does not
operate. To avoid this, before command input, clear the Command register. In an environment where system
noise occurs easily, Toshiba recommends input of a software or hardware reset before command input.
Protection Against Malfunction at Power-on
To prevent damage to data caused by sudden noise at power on, when power is turned on with WE = CEF =
VIL and OE = VIL, the device does not latch the command at the first rising edge of WE or CEF . The device
automatically resets the Command register and enters Read mode.
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