AN1849 Motorola / Freescale Semiconductor, AN1849 Datasheet - Page 21

• Manufacturer Part Number: AN1849
• Description: MPC107 Design Guide
• Manufacturer: Motorola / Freescale Semiconductor

Table 10 shows the various supported voltages.
The MPC107 core logic is quite a bit smaller than a PowerPC processor, so it requires much less power
(refer to the hardware specification for exact details). Since the power is low, there are several ways to
provide this power:
Figure 14 shows a simple linear regulator which will suffice in many instances for the core power needs of
the MPC107.
If 2.5V is needed elsewhere in the system, the MPC107 core power can be shared with other such devices.
L2 cache SRAMs, L2 I/O signals, and processor bus I/O drivers are can all be operated at 2.5V or less with
newer generations of PowerPC processors. If more power is needed, to minimize the heat dissipation
produced by higher-power linear regulators, a simple switching power supply can be used.
VDD
BVDD
OVDD
GVDD
LVDD
AVDD
LAVDD
GND
Power Group
•
•
•
Shared with other 2.5V supplies (such as L2 cache I/O)
Auxiliary output of a multiple-output switching power supply (as with the MPC7400)
Small linear regulator.
+5V
<1A
Internal (core) power
Processor I/O power
PCI/Other I/O power
Memory I/O power
PCI Clamp Voltage
PLL/DLL filtered power
Ground, common
3x
1.0uF
Function
Figure 14. Simple MPC107 Core Power Supply
Table 10. MPC107 Power Supplies
1
4
8
MPC107 Design Guide
3
CS8-2.5
LT1118
6
No. of Pins Nominal Voltage
15
24
16
25
6
2
64
7
2
2.5V
2.5V or 3.3V
3.3V
2.5V or 3.3V
3.3V or 5V
2.5V
ground
1.0uF
3x
0.1uF
+2.5V
<750mA
Interrupts, I
reset, NMI, JTAG
Separate filters required
Notes
2
C, PCI clocks,
Power
21