ia186es Innovasic Semiconductor Inc., ia186es Datasheet - Page 49

• Manufacturer Part Number: ia186es
• Description: 8-bit/16-bit Microcontrollers
• Manufacturer: Innovasic Semiconductor Inc.

IA186ES/IA188ES
8-Bit/16-Bit Microcontrollers
4.2
A phase-lock-loop (PLL) and a second programmable system clock output (clkoutb) are included
in the clock and power management unit. The internal clock is the same frequency as the crystal
but with a duty cycle of 45% to 55%, as a worst case, generated by the PLL obviating the need
for a 2X external clock. A POR resets the PLL (see Figure 8).
4.3
If required, the internal oscillator may be driven by an external clock source that should be
connected to x1, leaving x2 unconnected.
The clock outputs, clkouta and clkoutb, may be enabled or disabled individually (SYSCON
register Bits [11–8]). These clock control bits allow one clock output to run at PLL frequency
and the other to run at the power-save frequency (see Figure 9).
x1, x2
Clock and Power Management
System Clocks
PLL
C
C
1
2
®
Power-Save
(/2 to /128)
Divisor
Crystal
Figure 9. Organization of Clock
Figure 8. Crystal Configuration
UNCONTROLLED WHEN PRINTED OR COPIED
Processor Internal Clock
Mux
x1
x2
Mux
Page 49 of 154
IA211050902-15
Drive enable
IA186ES/
IA188ES
Time Delay
6 ±2.5nS
Drive enable
Recommended
range of values for
C
C
C
1
1
2
and C
= 15 pF ±20%
= 22 pF ±20%
2
are:
December 24, 2008
http://www.Innovasic.com
Customer Support:
Data Sheet
1-888-824-4184
clkouta
clkoutb