yekta ayduk

Power up problem :LTC3589 PMIC - i.mx536

Discussion created by yekta ayduk on Apr 12, 2012
Latest reply on Jun 6, 2012 by yekta ayduk
Hi,
I'm using LTC3589 for powering freescale imx536 processor.
My assumption was  that without accessing using I2C_SDA and I2C_SCLK ,
using the default values in the  LxDTVx and BxDTVx ,
and using R1 and R2 resistor values I can power up the system .

But during the measurements I have observed the following problem:

Altough Power_ON is continously high following signals
have only the the intended  values for 14 msecs within one second period.
--------------------------------------------------------------
LTC_WAKE ,
LDO2_1V3 ,
LDO4_2V8 ,
SW1_1V1  ,
SW2_1V3  ,
SW3_2V5  ,
VDD_ANA_PLL

Following signals are continously high (at expected values)
-----------------------------------------------------------
LDO1_1V3,
LDO3_2V8,
SW4_3V3

My Board configuraion is as follows :
For power on sequencing ,I have connected the enables and regulator outputs as follows.

By forcing the POWER_ON pin to high  the WAKE signal will be high.

WAKE= ENable-2    => SW2_1V3  will be up

SW2_1V3 =Enable-3 => SW3_2V5  will be up

Sw3_2V5 =VDD_REG of imx53  imx53 internal regulators will be up VDD_ANA_PLL=1.8V
will be generated

VDD_ANA_PLL=En_LDO2=En_LDO34 =>SW1_1V1 , LDO3_2V8 ,LDO4_2V8,LDO2_1V3  will be up

VDD_ANA_PLL=Enable of TPS54218(for 1V8 DDR2 voltage generation)

DDR2_1V8=Enable-4 => SW4_3V3 will be up

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