Toshiba H1 Series Data Book page 629

3.25.4 Notes of Power sequence
• Power ON/Power OFF Sequence (Initial Power ON/Complete Power OFF)
In the power ON sequence (initial power ON), power must be supplied to internal circuits
first and then to external circuits, as shown below. In the power OFF sequence (complete
power OFF), power must be turned off from external circuits so that internal circuits are
turned off last.
Power ON
(DVCC1A, DVCC1B, DVCC1C) → (DVCC3A, DVCC3B, AVCC)
Power OFF
(AVCC, DVCC3A, DVCC3B) → (DVCC1C, DVCC1B, DVCC1A)
Power on
DVCC1A
DVCC1B
DVCC1C
1.5V rails should be
turned on first, followed
by 3.0V rails.
DVCC3A
DVCC3B
AVCC
Oscillator Wake-up time to be stable
＋20 system clock
RESET
PWE terminal
Note1: Although it is possible to turn on or off 1.5V and 3.0V rails simultaneously, external pins may temporarily
become unstable in this case. Therefore, if there is any possibility that this would affect external devices
connected with the TMP92CZ26A, external power supplies should be turned on or off while internal power
supplies are stable, as shown in the diagram above.
Note2: In the power ON sequence, 3V rails must not be turned on before 1.5V rails. In the power OFF sequence, 3V
rails must not be turned off after 1.5V rails.
Power Cut Mode (PMC)
Power increases and
stabilizes within 100 ms.
92CZ26A-626
Power off
Power decreases and
stabilizes within 100 ms.
TMP92CZ26A
3.0V rails should be
turned off first, followed by
1.5V rails.