lpcware

PLL Block diagram is not in the LPC82x datasheet or manual

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by larsen on Tue Nov 04 14:53:12 MST 2014
It was not before reading the tool http://www.lpcware.com/content/nxpfile/lpc8xx-clock-and-pll-configuration-tool that the significance of the MSEL and PSEL became clear.

It appears that the frequency conversion functionality of the PLL is not described in the datasheet or manual for LPC82x. In the above tool there is a diagram showing the functions inside the PLL. This is very useful and essential information in order to understand that
FCCO = FCLKIN * (MSEL+1) * (1< < PSEL)*2
FPLLOUT = FCCO /(2*(1< < PSEL)) = FCLKIN *(MSEL+1)


Am I right that this information (both diagram and equations) is missing from the datasheet and manual?
If yes, is this the right place to suggest an update of the documentation?

ps: left shift operator wrecks havoc in the formatting, that's why there are to many spaces in 1< <PSEL

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