Piotr "Curious" Slawinski pisze:
> a mozna prosic zrodlo tej informacji i ew. jakich producentow (i jakich
> pojemnosci) karty sa na to narazone?

Jutro wypytam kolegę z działu "hardware" - na razie znalazłem krótki
opis zjawiska:
http://www.freshpatents.com/-dt20090205ptan200900343
28.php?type=description

cytat:
During the read-out operation, the read voltage Vread is applied to
control gates of the deselected cell transistors and the ground voltage
is applied to a substrate (e.g., a bulk) of the deselected cell
transistors. The drains of the deselected cell transistors are supplied
with a predetermined voltage. The application of the read voltage Vread
and the ground voltage causes a bias condition during the read-out
operation.

As illustrated in FIG. 3, the bias condition can cause electrons to be
injected into a floating gate of the deselected cell transistor from the
substrate during the read-out operation. The electrons can result in an
unintentional programming (or soft programming) of a deselected cell
transistor in on-state (or erased state), which is referred to as a
'read disturbance'.

A read disturbance may cause threshold voltages of the on-state (or
erased state) memory cells to gradually increase. As noted by the shaded
area shown in FIG. 4, threshold voltages of the on-state memory cells
increase in proportion to number of read-out operations that are
performed. The voltage increases may cause some of the on-state memory
cells to be erroneously detected as off-cells, resulting in read fails.

As the number of read-out operations performed increases, the
probability of a read fail increases as shown in FIG. 5. If the number
of bit errors exceeds a permissible range, a block corresponding thereto
is treated as a bad block. The bad block containing the erroneous data
is replaced by a reserved memory block, which is stored in the flash
memory device. Here, the bad block is caused by a read disturbance, and
not worn out by repetition of the programming or reading operation.
Therefore, the bad block may be reused through erasure and replacement.

Tekst pochodzi o opisu patentu na przeciwdziałanie zjawisku - więc
możliwe że większość kart na rynku nie robi już takich numerów