SPRUJ17H March 2022 – October 2024 AM2631 , AM2631-Q1 , AM2632 , AM2632-Q1 , AM2634 , AM2634-Q1
Clock Generator PLL (Phase-Locked Loop) circuits are used in the device to multiply a lower-frequency reference clock to the required operating frequency of the respective subsystem(s). The reference clock can either be external crystal driver provided through ‘XTAL_XI’ pad or external reference clock provided through ‘EXT_REFCLK0’ pad. This selection can be provided using the TOP_RCM.PLL_REF_CLK_SRC_SEL register
The low-jitter ADPLLLJ module is use as the Device CORE and PER PLLs. A high level block diagram of the ADPLLLJ is shown in Figure 6-23.
The ADPLLLJ has the following input/output clocks
The ADPLLLJ can be programmed to be locked at any frequency given by the following equation:
Where:
fDPLL is the lock frequency.
PLL input values and status ouptuts are routed to TOP_RCM MMRs