lpcware

LPC1769 MCPWM Problem

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by Ulisses on Mon Dec 19 11:49:15 MST 2011
There is a problem in LPC1769 MCPWM module.

The System Frequency is 120 MHz and PCCLK = CCLK for the MCPWM.
It was setup for CENTER ALIGNED and ACMODE.

For switching frequency higher than 5 kHz and modulation index higher than 0.8 or lower than 0.2, it seems to stop working every 4-5 ms for about 2ms.

Example:
SystemFrequency = 120000000
PCCLK_MC = 1
LPC_MCPWM->LIM(0,1,2) = 12000
LPC_MCPWM->MAT(0,1,2) = 11500 or 500
LPC_MCPWM->CENTER(0,1,2) = 1
LPC_MCPWM->POLA(0,1,2) = 0
LPC_MCPWM->DTE(0,1,2) = 0
LPC_MCPWM->DISUP(0,1,2) = 0
INVBDC = 0
ACMODE = 1
DCMODE = 0

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