Datasheet

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RST AND PORRST TIMINGS
Timing Requirements for PORRST
V
CCP
/V
CCIO
V
CC
V
CCPORH
V
CCIOPORL
V
IL(PORRST)
V
CCIOPORH
V
CCIOPORH
V
CCIOPORL
V
CCPORL
V
CC
PORRST
V
CCIO
V
CCPORH
V
CCPORL
V
IL
V
IL
V
IL
V
IL
V
IL(PORRST)
V
CCP
/V
CCIO
V
CC
t
h(PORRST)rio
t
h(PORRST)r
t
su(PORRST)f
t
h(PORRST)r
t
su(PORRST)fio
t
su(PORRST)f
t
su(VCCIO)f
t
su(VCCIO)r
t
su(PORRST)r
t
h(PORRST)d
Switching Characteristics over Recommended Operating Conditions for RST
(1)
TMS470R1B1M
16/32-Bit RISC Flash Microcontroller
SPNS109A – SEPTEMBER 2005 – REVISED AUGUST 2006
(see Figure 9 )
MIN MAX UNIT
V
CCPORL
V
CC
low supply level when PORRST must be active during power up 0.6 V
V
CC
high supply level when PORRST must remain active during power up and become
V
CCPORH
1.5 V
active during power down
V
CCIOPORL
V
CCIO
low supply level when PORRST must be active during power up 1.1 V
V
CCIO
high supply level when PORRST must remain active during power up and become
V
CCIOPORH
2.75 V
active during power down
V
IL
Low-level input voltage after V
CCIO
> V
CCIOPORH
0.2 V
CCIO
V
V
IL(PORRST)
Low-level input voltage of PORRST before V
CCIO
> V
CCIOPORL
0.5 V
t
su(PORRST)r
Setup time, PORRST active before V
CCIO
> V
CCIOPORL
during power up 0 ms
t
su(VCCIO)r
Setup time, V
CCIO
>V
CCIOPORL
before V
CC
> V
CCPORL
0 ms
t
h(PORRST)r
Hold time, PORRST active after V
CC
> V
CCPORH
1 ms
t
su(PORRST)f
Setup time, PORRST active before V
CC
≤ V
CCPORH
during power down 8 µs
t
h(PORRST)rio
Hold time, PORRST active after V
CC
> V
CCIOPORH
1 ms
t
h(PORRST)d
Hold time, PORRST active after V
CC
< V
CCPORL
0 ms
t
su(PORRST)fio
Setup time, PORRST active before V
CC
≤ V
CCIOPORH
during power down 0 ns
t
su(VCCIO)f
Setup time, V
CC
< V
CCPORL
before V
CCIO
< V
CCIOPORL
0 ns
NOTE: V
CCIO
> 1.1 V before V
CC
> 0.6 V
Figure 9. PORRST Timing Diagram
PARAMETER MIN MAX UNIT
Valid time, RST active after PORRST inactive 4112t
c(OSC)
t
v(RST)
ns
Valid time, RST active (all others) 8t
c(SYS)
Flash start up time, from RST inactive to fetch of first instruction from flash (flash pump
t
fsu
836t
c(OSC)
ns
stabilization time)
(1) Specified values do NOT include rise/fall times. For rise and fall timings, see the "switching characteristics for output timings versus load
capacitance" table.
37
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