AnsweredAssumed Answered

Not getting sine wave when TX-LDO is operating at 3V(external tvdd)

Question asked by gokul krishna on Jul 9, 2018
Latest reply on Aug 3, 2018 by IvanRuiz

We are observing no change in wave-forms when the TXLDO_CONTROL_REG is changed. The TXLDO is configured as follows:

PH_REG_CLEAR_BIT(PMU_TXLDO_CONTROL_REG, TXLDO_ENABLE);
PH_REG_CLEAR_BIT(PMU_TXLDO_CONTROL_REG, TXLDO_LOW_POWER_EN);
PH_REG_CLEAR_BIT(PMU_TXLDO_CONTROL_REG,TXLDO_ENABLE_LP2);
PH_REG_SET_BIT(PMU_TXLDO_CONTROL_REG, TXLDO_LIMITER_EN);
PH_REG_SET_BIT(PMU_TXLDO_CONTROL_REG, TXLDO_OVERCURRENT_EN);
PH_REG_SET(PMU_INTERRUPT_SET_ENABLE_REG,PMU_INTERRUPT_SET_ENABLE_REG_TXLDO_OVERCURRENT_IRQ_SET_ENABLE_MASK);
PH_REG_SET_FIELD(PMU_TXLDO_CONTROL_REG, TXLDO_SELECT,E_TVDD_3M0_V);//3volt
PH_REG_SET_BIT(PMU_TXLDO_CONTROL_REG, TXLDO_ENABLE);

PH_REG_SET_FIELD(PMU_TXLDO_CONTROL_REG, TXLDO_SELECT_ANT,0x03);// TXLDO_DET_OUT  range of 100mA

 

No NFC cards are able to detect with the current wave-form.

pn7462au #TXLDO pn7462 low power pn7462au fw & sw examples nfc.

Outcomes