34
4.3
Clock System
CW6632B Bluetooth 3.0 Audio Player SOC
Version 1.0.0
Copyright ©2015, www.appotech.com. All Rights Reserved.
11 = 1MHz div form XOSC26M
pll_1m
rc1m
xosc_tclk
x26m_1m
00
01
10
11
MUX
CLKCON[1:0]
ir_clk
PCON0[3]
Figure 4-6 IR clock select figure
4.3.2
Clock Gating
CW6632B provides comprehensive clock gating options for eliminating power-wasting activities.
4.3.3
Phase Lock Loop (PLL)
CW6632B provides one on-chip Phase Locked Loop (PLL 48M) clock generators. The PLL has reference clock from
external 32 KHz/4M/12 M crystal oscillators to provide a stable reference clock and the reference clock is multiplied
to provide the final PLL output.
Register 4-9 PLLCON
– PLL Configuration
Position
7
6
5
4
3
2
1
0
Name
SDADCLKEN
Reserved
SDADCCLK_SEL
PLL12DREF_SEL
PLL1 DREF_SEL
Default
0
0
0
0
0
0
0
0
Access
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
PLL1AREF_SEL
: PLL1 input reference clock digital select
00 = XOSC
01 = RCOSC
10 = RCOSC div
11 = Reserved
PLL2AREF_SEL
: PLL2 input reference clock digital select
00 = XOSC
01 = RCOSC
10 = PLL1 div
11 = Reserved
SDADCCLK_SEL
: SDADC clockl select
00 = XOSC inv
01 = XOSC
10 = PLL2 div2 inv