TC58FVT641 datasheet(18/53 Pages) TOSHIBA

18 / 53 page

TC58FVT641/B641FT/XB-70,-10

2001-09-06

18/53

DATA PROTECTION

The TC58FVT641/B641 includes a function which guards against malfunction or data corruption.

Protection against Program/Erase Caused by Low Supply Voltage

To prevent malfunction at power-on or power-down, the device will not accept commands while VDD is below

VLKO. In this state, command input is ignored.

If VDD drops below VLKO during an Auto Operation, the device will terminate Auto-Program execution. In

this case, Auto operation is not executed again when VDD return to recommended VDD voltage Therefore,

command need to be input to execute Auto operation again.

When VDD > VLKO, make up countermeasure to be input accurately command in system side please.

Protection against Malfunction Caused by Glitches

To prevent malfunction during operation caused by noise from the system, the device will not accept pulses

shorter than 3 ns (Typ.) input on WE , CE or OE . However, if a glitch exceeding 3 ns (Typ.) occurs and the

glitch is input to the device malfunction may occur.

The device uses standard JEDEC commands. It is conceivable that, in extreme cases, system noise may be

misinterpreted as part of a command sequence input and that the device will acknowledge it. Then, even if a

proper command is input, the device may not operate. To avoid this possibility, clear the Command Register

before command input. In an environment prone to system noise, Toshiba recommend 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 = CE =

VIL the device does not latch the command on the first rising edge of WE or CE . Instead, the device

automatically Resets the Command Register and enters Read Mode.

TC58FVT641 データシート(PDF) 18 Page - Toshiba Semiconductor