SH7619_09 Datasheet, PDF (771/860 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7619 Series

Section 25 Electrical Characteristics
The time over which the internal state is undefined means the time taken to reach Vcc (min.).
The pin states become settled when VccQ and VccnA (n = 1 to 3) reached the VccQ (min.). The
timing when a power-on reset (RES) is normally accepted is after Vcc reaches Vcc (min.) and
oscillation becomes stable (when using the on-chip oscillator).
Ensure that the time over which the internal state is undefined is less than or equal to 100 ms.
• Power-off order
 In the reverse order of power-on, first turn off the 1.8-V system power, then turn off the
3.3-V system power within 10 ms. This time should be as short as possible. The system
design must ensure that the states of pins or undefined period of an internal state do not
cause erroneous system operation. In some systems, Vcc may exceed 3.3-V system power
(Vcc > 3.3-V system power) temporarily, on the falling edge. Even in this case, the
inverted potential difference must be 0.3 V or less.
 Pin states are undefined while only the 1.8-V system power is turned off. The system
design must ensure that these undefined states do not cause erroneous system operation.
VccQ: 3.3-V system power
VccnA: 3.3-V system power*
Vcc : 1.8-V system power
GND
Vcc/2
Normal operation period
Note: * n = 1 to 3
t_PWD
Operation stopped
max 0.3V
Table 25.3 Recommended Timing in Power-Off
Item
Symbol Maximum Value Unit
Time difference between turning off VccQ, VccnA (n = 1 t
10
ms
PWD
to 3), and Vcc
Note: * The table shown above is recommended values, so they represent guidelines rather
than strict requirements.
Rev. 6.00 Jul. 15, 2009 Page 731 of 816
REJ09B0237-0600