Samsung S5PC100 User Manual page 789

S5PC100 USER'S MANUAL (REV1.0)
4 DPHY PLL CONTROL
4.1 PMS SETTING SAMPLE FOR MIPI PLL
4.1.1 PMS setting
Write a value to PMS field in DSIM_PLLCTRL (0xECB0_004C) to set PMS value for DPHY PLL. Each P, M and S
resides in PMS [19:14] , PMS[13:4] and PMS[3:1] . Before Setting, PMS value please read the following:
1. Do not set the P or M value as zero, that is, setting the P(00000), M(0000000000) causes malfunction of the
PLL.
2. Select M and P considering stability and VCO range
3. Keep range of Fin_pll from 2.5 MHz to 5 MHz, by P code setting
Function
Fin
Fin_pll Fin_pll
VCO_out (M*Fin)/P
Fout (M*Fin)/(P*2^S)
P[5:0]
M[9:0]
S[2:0]
4.1.2 Sample for Fout 80 MHz
Followings are some example to set PMS value for Fout 80 MHz
Fin
Fin_pll
P[5:0]
M[9:0]
S[2:0]
VCO_out
Fout
Table 8.7-5 PMS and frequency constraint
Value
Fin 3~200MHz
2.5 ~ 5 MHz
500 ~ 1000 MHz
16 ~ 1000 MHz
P 1 ~ 63
M 100 ~ 1023
2^S 1, 2, 4, 8, 16, 32
Pll input frequency
Pfd input frequency
VCO output frequency
PLL output frequency
PMS[19:14]
PMS[13:4]
PMS[3:1]
Case 1
24MHz
4MHz
6
160
8
640MHz
80MHz
Description
Case 2
4MHz
4MHz
1
160
8
640MHz
80MHz
MIPI DSIM
8.7-33