AM186ES Advanced Micro Devices, AM186ES Datasheet - Page 41

• Manufacturer Part Number: AM186ES
• Description: microcontrollers provide a low-cost/ high-performance solution for embedded system designers who wish to use the x86 architecture.
• Manufacturer: Advanced Micro Devices

Clock Sharing by System and USB
The system and USB clocks can be generated from a
single source in one of two ways:
n The system can run at 48 MHz by using the system
Note: When using the system clock for the USB clock
source, the designer must externally pull down the
USBX1 input.
clock for the USB clock.
USBX1
X1
X2
USBX2
Am186™CC Communications Controller Data Sheet
Figure 8. System and USB Clock Generation
{CLKSEL2}–{CLKSEL1}
PLL Bypass Mode
{USBSEL2}–{USBSEL1}
PLL
Am186CC Controller
PLL
1x
2x
4x
2x
4x
n The system can be run at 24 MHz by sharing an
exter nal clock reference (X1) with the USB
(USBX1). A 12-MHz source can be used with the
system PLL in 2x mode and the USB PLL in 4x
mode, or a 24-MHz source can be used with the
system in 1x mode and the USB in 2x mode.
System Clock
USB Clock
48-MHz
CLKOUT
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