topic Re: LPC54102 at max cpu clock (150MHz) in LPC Microcontrollers

LPC54102 at max cpu clock (150MHz)

grosdode — Fri, 17 May 2024 11:35:50 GMT

I try to use the LPC54102 at the maximum speed of 150MHz or at least above 100MHz, but can't get it to work. As a minimum example I tried this:

open MCUXpresso IDE v11.9.0 [Build 2144] [2024-01-05]
Create a new project
- File --> new --> Create a new C/C++ project ...
- Choose lpcxpresso54102
- everything else as default
open the Clock tool and change the PLL to 120MHz in the Clocks Diagram
Update Code
Build
Debug as MCUXpresso IDE LinkServer (inc. CMIS-DAP) probes
press Run (Resume / F8)
- --> crash
open the Clock tool and change the PLL to 96MHz in the Clocks Diagram
Update Code
Build
Debug as MCUXpresso IDE LinkServer (inc. CMIS-DAP) probes
press Run (Resume / F8)
- everything is fine

The Programm crashes in fsl_clock.c in line 151:

pClkSel[mux] = sel;

when called from clock_config.c with:

CLOCK_AttachClk(kSYS_PLL_OUT_to_MAIN_CLK); /*!< Switch MAIN_CLK to SYS_PLL_OUT */

Re: LPC54102 at max cpu clock (150MHz)

grosdode — Fri, 17 May 2024 11:42:30 GMT

More pictures and exported project (5 was the limit)

Re: LPC54102 at max cpu clock (150MHz)

Pablo_Ramos — Fri, 17 May 2024 22:35:20 GMT

Hi @grosdode
We are investigating your problem, but we would need more information about the marking code of the chip, please send us a photo of the chip.
Thanks.

Re: LPC54102 at max cpu clock (150MHz)

grosdode — Tue, 21 May 2024 05:16:42 GMT

Picture is attached

Re: LPC54102 at max cpu clock (150MHz)

Pablo_Ramos — Tue, 21 May 2024 21:30:03 GMT

Hi again @grosdode ,

I noticed that there is a typo in the LPC541xx documentation. An apology for the inconvenience.

There is an errata about the maximum operating system clock in ES_LPC5410X, where is stated that the maximum operating system clock on the LPC5410x device (rev 1B) is limited to 96 MHz.

Errata sheet LPC5410x (nxp.com)

An also in SDK examples (for example hello world) there is also a note that apply for the rev 1C (which you have) where is mentioned that rev 1C is limited to 100Mz.

So please operate your application under these limits.

Hope it helps you!

Re: LPC54102 at max cpu clock (150MHz)

grosdode — Wed, 22 May 2024 06:56:22 GMT

Hi Pablo,

thank you for the information, but why is this only mentioned in some example code an not in the errata? I even have a rev. 1D Controller here (custom board) at my desk and it is also not working above 100MHz, can you confirm that no controller version can operate above 100MHz? Does NXP just continue to lie in the datasheet? Because this IC is advertised everywhere with a speed up to 150MHz.

Re: LPC54102 at max cpu clock (150MHz)

grosdode — Thu, 23 May 2024 06:21:30 GMT

I upgraded one Evaluation board to the Rev. 1D same problem.

Re: LPC54102 at max cpu clock (150MHz)

Pablo_Ramos — Mon, 03 Jun 2024 19:00:52 GMT

Hi, @grosdode
An apology for the confusion I notice that there is a new version where this issue is fixed. Rev C can run PLL up to 150MHz.

Please use the SDK version 2.6.1, there is a new function that let you to init the PLL to 150MHz, also it solves the note (or SW errata) about the Rev C, you just need to change the function BOARD_InitBootClocks(); to now use BOARD_BootClockPLL150M();

This should work also for Rev D.

Rev B is still limited to 96MHz

Hope it helps you.