Cypress EZ-USB CX3 User Manual

Cypress EZ-USB CX3
EZ-USB® CX3 Technical Reference Manual, Doc. No. 001-91492 Rev. *B 12
Table 4: PLL Clock Frequency Calculation example
REFCLK in MHz
PLL_PRD
PLL_FBD
PLL_FRS
PLL_CLK in MHz
19.2
1
69
0
672
19.2
1
69
2
168
19.2
3
201
1
484.8
19.2
2
97
3
78.4
19.2
2
125
1
403.2
1.7.3 CSI RX LP  HS Clock
This clock is used for detecting the CSI Link Low Power (LP)  High Speed (HS) transition. It is generated
by dividing the PLL_CLK by a value of 2, 4, or 8. Details regarding the CSI Link LP  HS transitions can
be found in the MIPI CSI-2 specification documentation available from the MIPI alliance
(http://www.mipi.org/specifications/camera-interface).
The maximum value for this clock is 125 MHz.
This clock frequency is calculated automatically by the “MIPI Receiver configuration tool”.
1.7.4 Output Parallel Clock (PCLK)
This clock is the PCLK output, which drives the fixed-function GPIF II interface on CX3. It is generated by
dividing the PLL_CLK by a value of 2, 4, or 8.
The maximum value for this clock is 100 MHz.
This clock frequency is calculated automatically by the “MIPI Receiver configuration tool”.
1.7.5 Image Sensor Reference Clock (MCLK)
The MCLK is an optional clock output that can be used as the input reference clock for the image sensor. It is
sourced from the PLL_CLK by first dividing down using the mClkRefDiv (2/4/8) and then dividing further using
the MCLKCTL divider. The MCLKCTL divider specifies the HIGH time and LOW time counted by the divided
down PLL_CLK.
The upper eight bits define the HIGH time count (1-255) and the lower eight bits define the LOW time count
(1-255).
MCLK is computed using the following equation:
MCLK = ( PLL_CLK/mClkRefDiv ) / [ ( HighByte (mClkCtl) + 1 ) + ( LowByte (mClkCtl) + 1 ) ]
For example:
If the PLL_CLK is 672 MHz, to generate MCLK of 24 MHz, set mClkRefDiv to 4 and mClkCtl to 0x0203.
Thus:
MCLK = ( 672 / 4 ) / ( (2 + 1) + ( 3 + 1 ) )
= 168 / 7 = 24 MHz
MCLK is the only output when both HighByte ( MClkCtl ) and LowByte ( MclkCtl ) are non-zero.
This clock frequency is calculated automatically by the “MIPI Receiver configuration tool”.

Cypress EZ-USB CX3 Specifications

General

Brand	Cypress
Model	EZ-USB CX3
Category	Controller
Language	English