TMS320F28030 Datasheet, PDF (110/157 Pages) Texas Instruments – Piccolo Microcontrollers

TMS320F28030, TMS320F28031, TMS320F28032
TMS320F28033, TMS320F28034, TMS320F28035
SPRS584E – APRIL 2009 – REVISED MARCH 2011
www.ti.com
6.9 Power Sequencing
There is no power sequencing requirement needed to ensure the device is in the proper state after reset
or to prevent the I/Os from glitching during power up/down. However, it is recommended that no voltage
larger than a diode drop (0.7 V) should be applied to any pin prior to powering up the device. Voltages
applied to pins on an unpowered device can bias internal p-n junctions in unintended ways and produce
unpredictable results.
V_DDIO, V_DDA
(3.3 V)
V_DD (1.8 V)
INTOSC1
t_INTOSCST
X1/X2
t_OSCST
(B)
(A)
XCLKOUT
(D)
XRS
Address/Data/
Control
(Internal)
Boot-Mode
Pins
t_w(RSL1)
User-code dependent
Address/data valid, internal boot-ROM code execution phase
t_d(EX)
t_{h(boot-mode)(C)}
GPIO pins as input
Boot-ROM execution starts
User-code execution phase
User-code dependent
Peripheral/GPIO function
Based on boot code
I/O Pins
GPIO pins as input (state depends on internal PU/PD)
User-code dependent
A. Upon power up, SYSCLKOUT is OSCCLK/4. Since the XCLKOUTDIV bits in the XCLK register come up with a reset
state of 0, SYSCLKOUT is further divided by 4 before it appears at XCLKOUT. XCLKOUT = OSCCLK/16 during this
phase.
B. Boot ROM configures the DIVSEL bits for /1 operation. XCLKOUT = OSCCLK/4 during this phase. Note that
XCLKOUT will not be visible at the pin until explicitly configured by user code.
C. After reset, the boot ROM code samples Boot Mode pins. Based on the status of the Boot Mode pin, the boot code
branches to destination memory or boot code function. If boot ROM code executes after power-on conditions (in
debugger environment), the boot code execution time is based on the current SYSCLKOUT speed. The SYSCLKOUT
will be based on user environment and could be with or without PLL enabled.
D. Using the XRS pin is optional due to the on-chip power-on reset (POR) circuitry.
Figure 6-8. Power-on Reset
110 Electrical Specifications
Copyright © 2009–2011, Texas Instruments Incorporated
Submit Documentation Feedback
focus.ti.com: TMS320F28030 TMS320F28031 TMS320F28032 TMS320F28033 TMS320F28034 TMS320F28035