Motorola MPC823e User Manual

Clocks and Power Control
MOTOROLA MPC823e REFERENCE MANUAL 5-31
CLOCKS AND POWER
5
CONTROL
When a timer expires, if enabled, the TEXP pin is asserted asynchronously with CLKOUT
to show that the MPC823e is preparing to exit power-down mode. TEXP must be externally
connected to a switch that must turn on the power supply to the chip, as illustrated in
Figure 5-16.
In normal and doze modes, the system can be in the high mode defined by the DFNH field
or in the low mode defined by the DFNL field. The MPC823e is in normal high mode after
reset and this also the default state when the condition to exit low-power mode occurs.
Table 5-7 provides the power consumption equations for each of these modes
Table 5-7. MPC823e Low-Power Modes
OPERATION
MODE
UDR2 (.42µ)
EQUATION
POWER @
50MHZ
UDR2
(.42µ)
CDR2 (.36µ) EQUATION POWER @
25MHZ
CDR2
(.36µ)
POWER @
50MHZ
CDR2
(.36µ)
POWER @
66MHZ
CDR2
(.36µ)
Normal High
LPM=00
TEXPS=1
≅ 20 mW + (.78)/2
DFNH
W
860mW
≅ 20 mW + (.555)/2
DFNH
W
298 mW 575 mW 750 mW
Normal Low
LPM=00
TEXPS=1
≅ 20 mW + (.78)/2
(DFNL+1)
W
450 mW
≅ 20 mW + (.555)/2
(DFNL+1)
W
159 mW 298 mW 385 mW
Doze High
LPM=01
TEXPS=1
≅ 20mW + 0.4(.78)/2
DFNH
W
356 mW
≅ 20 mW + 0.4(.555)/2
DFNH
W
132 mW 242 mW 312 mW
Doze Low
LPM=01
TEXPS=1
≅ 20 mW + 0.4(.78)/
2
(DFNL+1)
W
188 mW
≅ 20 mW + 0.4(.555)/2
(DFNL+1)
W
76 mW 131 mW 166 mW
Sleep LPM=10
TEXPS=1
— 10 mW — 10 mW 10 mW 10 mW
Deep-Sleep
LPM=11
TEXPS=1
— 40µA — 40µA 40µA 40µA
Power-Down
LPM=11
TEXPS=0
— 10µA — 10µA 10µA 10µA
NOTE: The above currents are measured at 3.3V.
Note: The communication processor module has its own power conservation logic,
which it uses to automatically shut down its own clock when idle.

Motorola MPC823e Specifications

General

Brand	Motorola
Model	MPC823e
Category	Computer Hardware
Language	English