OMAP-L138_0908 Datasheet, PDF (73/268 Pages) Texas Instruments – OMAP-L138 Low-Power Applications Processor

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OMAP-L138 Low-Power Applications Processor
SPRS586A – JUNE 2009 – REVISED AUGUST 2009
6.2 Recommended Clock and Control Signal Transition Behavior
All clocks and control signals must transition between V_IH and V_IL (or between V_IL and V_IH) in a monotonic
manner.
6.3 Power Supplies
6.3.1 Power-on Sequence
The device should be powered-on in the following order:
• 1) RTC (RTC_CVDD) may be powered from an external device (such as a battery) prior to all other
supplies being applied. If the RTC is not used, RTC_CVDD should be connected to CVDD.
• 2a) All variable 1.2V - 1.0V core logic supplies (CVDD)
• 2b) All static 1.2V logic supplies (RVDD, VDDA_12_PLL0, VDDA_12_PLL1, USB_CVDD,
SATA_VDD). If voltage scaling is not used on the device, groups 2a) and 2b) can be controlled from
the same power supply and powered up together.
• 3) All static 1.8V IO supplies (DVDD18, DDR_DVDD18, USB0_VDDA18, USB1_VDDA18 and
SATA_VDDR) and any of the LVCMOS IO supply groups used at 1.8V nominal (DVDD3318_A,
DVDD3318_B, or DVDD3318_C).
• 4) All analog 3.3V PHY supplies (USB0_VDDA33 and USB1_VDDA33; these are not required if both
USB0 and USB1 are not used) and any of the LVCMOS IO supply groups used at 3.3V nominal
(DVDD3318_A, DVDD3318_B, or DVDD3318_C).
There is no specific required voltage ramp rate for any of the supplies as long as the LVCMOS supplies
operated at 3.3V (DVDD3318_A, DVDD3318_B, or DVDD3318_C) never exceed the STATIC 1.8V
supplies by more than 2 volts.
6.3.2 Power-off Sequence
The power supplies can be powered-off in any order as long as LVCMOS supplies operated at 3.3V
(DVDD3318_A, DVDD3318_B, or DVDD3318_C) never exceed static 1.8V supplies by more than 2 volts.
There is no specific required voltage ramp down rate for any of the supplies (except as required to meet
the above mentioned voltage condition).
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Peripheral Information and Electrical Specifications
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