SH7764 Datasheet, PDF (1630/1752 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperHTM RISC Engine Family SH-4A Series

Section 33 Electrical Characteristics
33.2 Power-on/Power-off Sequence
The sequences for turning on and off power supplies are shown below together with recommended
values.
3.3 V power voltage
3.3 V minimum power voltage
1.2 V power voltage
1.2 V minimum power voltage
GND
t_UNC
Pins status
undefined
Normal operation period
t_UNC
Pins status
undefined
3.3 V power: V_DDQ, V_{DDQ_USB}, V_{DDQA_USB}
1.2V power: V_DD, V_{DD_PLL1}, V_{DD_PLL2}, V_{DD_USB}, V_{DDA_USB}, UV12
Figure 33.1 Power-on/Power-off Sequence
Table 33.2 Recommended Time for Power-on/Power-off Sequence
Item
Symbol
Max.
Unit
State undefined time tUNC
100
ms
Note:
The table shown above is the maximum values, so they represent guidelines rather than
strict requirements.
Either the 3.3-V power supply or the 1.2-V power does not matter to be turned on or turned
off. An undefined time appears until either of the power supply, which turns on later,
reaches above the minimum voltage and after it has reached below the minimum voltage.
During these periods, pin and internal states become undefined. Design the system so that
these undefined states do not cause an overall malfunction.
Rev. 1.00 Nov. 22, 2007 Page 1574 of 1692
REJ09B0360-0100