How do i turn on the boost mode on the S2-LP ?

[AndyR1]

Hi,

SMPS voltage is settable as in page 74 of the datasheet PM_CONF0, you should configure SMPS_LVL_MODE in PM_CONF1 too :

void EnableBoostMode( void )
{
    uint8_t tmp;
    
    S2LPSpiReadRegisters(PM_CONF1_ADDR, 1, &tmp);
    tmp &= (~SMPS_LVL_MODE_REGMASK);
    tmp |= SMPS_LVL_MODE_REGMASK;    /*< SMPS_LVL_MODE for Rx and Tx or just Tx >*/
    *(uint8_t*)&g_xStatus = S2LPSpiWriteRegisters(PM_CONF1_ADDR, 1, &tmp);
    
    S2LPSpiReadRegisters(PM_CONF0_ADDR, 1, &tmp);
    tmp &= (~SET_SMPS_LVL_REGMASK);
    tmp |= SET_SMPS_LVL_1_8V;    /*< Maximum value >*/
    *(uint8_t*)&g_xStatus = S2LPSpiWriteRegisters(PM_CONF0_ADDR, 1, &tmp);
}

Andy.

[Massimiliano Di Rugggiero]

Hi,

in my FK433V2 evaluation board I can't reach 16 dBm.

I set:

• SMPS_LVL to 1800 mV in PM_CONF0
• SMPS_LVL_MODE set to 1 in PM_CONF1, i.e. max supply only during Tx
• PA_LEVEL_7 set to 1 in PA_POWER8

I this condition I measure 12,9 dBm in CW with the spectrum analyzer.

If I set SMPS_LVL to 1500 mV the measured power is 11,6 dBm.

Is there a limitation of the FK433V2 evaluation board?

Thank You

Massimiliano