TI E2E Community
Digital Signal Processors (DSP)
OMAP-L13x, AM1x and C674x Processors Forum
minimum time for release of reset after powerup on OMAPL-138
I would like to minimise the boot time when using the OMAPL-138
I can find nothing in the documentation regarding when RESET can be de-asserted after power up - other than the voltages must have stabilized and the reset must be low for a minimum of 100ns.
The PMIC used on the LogicPD EVM uses the TPS65070 which releases reset only 400ms after the last supply has stabilized. Are there any other considerations than stable power - clock maybe - that would require a 0.4 sec delay?
Yep, you've got it. Power must be stable and clocks must be stable. There is a diagram in the datasheet, Figure 6-4, that indicates the OSCIN clock input should be stable before the release of reset.
I would also state, that it is important for the boot mode selection pins, described in Section 3.9.11, should be in a stable state before the release of reset. These will determine which mode the device boots in and is selected when reset is deasserted.
Why in the newest omap-l132 datasheet http://www.ti.com/product/omap-l138 http://www.ti.com/product/omap-l132 don't has the Figure 6-4 describe about the timing delay .Can you tell me the in the slva371b.pdf ( http://www.ti.com/lit/an/slva371b/slva371b.pdf ), what is the ” timing delay “ ？
All content and materials on this site are provided "as is". TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with regard to these materials, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement of any third party intellectual property right. TI and its respective suppliers and providers of content make no representations about the suitability of these materials for any purpose and disclaim all warranties and conditions with respect to these materials. No license, either express or implied, by estoppel or otherwise, is granted by TI. Use of the information on this site may require a license from a third party, or a license from TI.
TI is a global semiconductor design and manufacturing company. Innovate with 100,000+ analog ICs andembedded processors, along with software, tools and the industry’s largest sales/support staff.