Specifications

88 Élan™SC310 Microcontroller Data Sheet
PRELIMINARY
AC Switching Characteristics over Commercial Operating Ranges
Notes:
1. This parameter is dependent on the 32 kHz oscillator start-up time. The oscillator start-up time is dependent on the external
component values used, board layout, and power supply noise. For more information, see “Crystal Specifications” on page
84.
2. RESIN
remains inactive during Micro Power Off mode and Micro Power Off mode exit.
3. The pulse width of RSTDRV is adjustable based on PLL start-up timing. See “Loop Filters” on page 86 for more information.
Voltage sequencing on power-up for the ÉlanSC310 microcontroller should be observed as follows:
–VCC
– All VCC clamp sources (VCC, VMEM, VSYS, VCC5, and AVCC)
– All VCCIO sources (VCC5, VMEM, VSYS, VCC1, VSYS2, and AVCC)
The reverse is true when powering down. For any particular I/O pin, the VCCIO may come up simultaneously with the VCC clamp,
but should never proceed the VCC clamp. Refer to the Pin Characteristics table (page 21) for detailed I/O information.
Table 45. Power-Up Sequencing (See Figures 32–35)
Symbol Parameter Description Notes
Preliminary
Unit
Min Typ Max
t1 All VCC valid to RESIN and IORESET inactive 1, 2 1 s
t2 RESIN
and IORESET inactive to RSTDRV inactive 2, 3 300 µs
t3 IORESET
active to RSTDRV active 0 ns
t4 VSYS2, VCC1, and VSYS valid delay from VCC5 0 ns
t5 VSYS2, VCC1, VSYS, and optionally VMEM valid to
IORESET
inactive
5 µs
t6 VCC5, VSYS2, VCC1, VSYS hold time from IORESET
active
5 µs
t7 VCC5 hold time from VSYS2, VCC1, and VSYS inactive 0 ns