The module has a 24 MHz SMD clock oscillator providing a clock source for both the EZ-USB FX2LP USB FX2 microcontroller (XTALIN) and the FPGA as detailed in the table below.
signal | FPGA pin | FPGA ball | FPGA bank |
---|---|---|---|
24MHZ1 | IO_L28N_2 | AE14 | 2 |
The DCMs of the FPGA can be used to synthesize arbitrary clock frequencies from any on-board clock network, differential clock input pair or single-ended clock input. For further reference, please read Xilinx DS485:Digital Clock Manager (DCM) Module and the DCM chapter in Xilinx UG331: Spartan-3 Generation FPGA User Guide.
The IFCLK line synchronizes the communication between the EZ-USB FX2LP USB FX2 microcontroller and the FPGA as detailed in the table below .
signal | FPGA pin | FPGA ball | FPGA bank |
---|---|---|---|
IFCLK | IO_L31N_1 | P25 | 1 |
The module has a main SMD clock oscillator providing a clock source for the FPGA as detailed in the table below.
signal | FPGA pin | FPGA ball | FPGA bank |
MAINCLK | IO_L27N_2 | AA14 | 2 |
Standard frequency is 100 MHz. Should you wish or need another main clock oscillator frequency, please contact Trenz Electronic. The lower the main clock frequency, the lower the module power consumption. Moreover, as the main clock is preferably used as DDR SDRAM clock, a lower clock frequency makes easier for the development tools to meet the timing requirements (particularly for DDR SDRAM).