Infineon Cypress S29GL01GS, Manual

Page: 71 / 109

Document Number: 001-98285 Rev. *R Page 70 of 108
S29GL01GS/S29GL512S
S29GL256S/S29GL128S
10.4.2 Power Supply Voltages
Operating ranges define those limits between which the functionality of the device is guaranteed.
10.4.3 Power-Up and Power-Down
During power-up or power-down V
CC
must always be greater than or equal to V
IO
(V
CC

V
IO
).
The device ignores all inputs until a time delay of t
VCS
has elapsed after the moment that V
CC
and V
IO
both rise above, and stay
above, the minimum V
CC
and V
IO
thresholds. During t
VCS
the device is performing power on reset operations.
During power-down or voltage drops below V
CC
Lockout maximum (V
LKO
), the V
CC
and V
IO
voltages must drop below V
CC
Reset
(V
RST
) minimum for a period of t
PD
for the part to initialize correctly when V
CC
and V
IO
again rise to their operating ranges. See
Figure 10.2 on page 71 . If during a voltage drop the V
CC
stays above V
LKO
maximum the part will stay initialized and will work
correctly when V
CC
is again above V
CC
minimum. If the part locks up from improper initialization, a hardware reset can be used to
initialize the part correctly.
Normal precautions must be taken for supply decoupling to stabilize the V
CC
and V
IO
power supplies. Each device in a system
should have the V
CC
and V
IO
power supplies decoupled by a suitable capacitor close to the package connections (this capacitor is
generally on the order of 0.1 µF). At no time should V
IO
be greater then 200 mV above V
CC
(V
CC

V
IO
–200 mV).
Note:
1. Not 100% tested.
Figure 10.1 Power-up
V
CC
2.7 V to 3.6 V
V
IO
1.65 V to V
CC
+200 mV
Table 10.3 Power-Up/Power-Down Voltage and Timing
Symbol Parameter Min Max Unit
V
CC
V
CC
Power Supply 2.7 3.6 V
V
LKO
V
CC
level below which re-initialization is required (Note 1) 2.25 2.5 V
V
RST
V
CC
and V
IO
Low voltage needed to ensure initialization will occur
(Note 1)
1.0 – V
t
VCS
V
CC
and V
IO

minimum to first access (Note 1) 300 – µs
t
PD
Duration of V
CC

V
RST
(min) (Note 1) 15 – µs
V cc (m a x)
V cc (m in )
P o w e r S u p p ly
V o lta g e
tim e
t
VCS
F u ll D e vice A cce ss
V cc
V
IO
(m in )
V
IO
(m a x)
V
IO