Motorola MPC823e User Manual

Clocks and Power Control
MOTOROLA MPC823e REFERENCE MANUAL 5-25
CLOCKS AND POWER
5
CONTROL
All other circuits are powered by the normal supply pins—VDDH and VDDL—and VSS.
VDDH feeds the I/O buffers and logic and VDDL supplies the internal chip logic to reduce
system power consumption. However, the power supply connected to VDDH must be larger
or equal to the one connected to VDDL. The power supply for each block is listed in Table 5-
5 and described in Section 5.4 Power Control .
The following are the power supply requirements of the MPC823e:
• VDDH = VDDSYN = 3.3V
±
5%
• VDDH
≥
VDDL
≥
3.3V
±
5%
• VDDH ≥ KAPWR ≥ VDDH – 0.4V for normal operation
• KAPWR
≥
2.5V
±
5% in power-down mode
5.4.2 Keep-Alive Power
When the MPC823e is in normal operation mode, the keep-alive power supply (KAPWR) is
powered to the same voltage value as that of the I/O buffers and logic. Therefore, if the
VDDL and VDDH is 3.3V, then the KAPWR is 2.9V to 3.3V.
Table 5-5. MPC823e Power Supply
BLOCK VDDH VDDL VDDSYN KAPWR
I/O Pad X
CLKOUT X
Digital SPLL X
Clock Control X X
Internal Logic X
Clock Drivers X
Analog SPLL X
Main Clock Oscillator X
SCCR, PLPRCR, and RSR X
Real-Time Clock, Periodic
Interrupt Timer, Timebase and
Decrementer
X

Motorola MPC823e Specifications

General

Brand	Motorola
Model	MPC823e
Category	Computer Hardware
Language	English