2024-09-15 03:21 AM
Hi,
I have several questions regarding current consumption numbers as they appear in the Datasheet of the STM32WLE5.
in Table 28 / Table 29 the current consumption of LORA RX/TX modes is mentioned.
I have several questions:
1. is it possible to use a TCXO on board and not supply its VDD=1.8V from PB0_VDD_TCXO pin , supply it from an external on board LDO instead?
2. if i chose to supply the TCXO VDD from PB0_VDD_TCXO pin - does the current consumption numbers ,that appear in table 28/Table 29 , include this current consumption ? if not - what is the delta current for this in each power state (RF RX , RF TX , RF not used) ?
3. is the internal on chip regulator that supply the PB0_VDD_TCXO - an LDO or SMPS ?
Thank you,
Viola
2024-09-17 11:59 PM
Hi ,
Any update regarding those issues?
Thank you,
Viola
2024-09-20 08:39 AM
Hello @viola
1- Yes, you can. The TCXO supply can be provided by the STM32WL on PB0/VDDTCXO or independently to save one GPIO. Keep in mind that the HSEBYPPWR bit 23 of RCC clock control register (RCC_CR) is set and cleared by software to control the function on package pin
PB0-VDDTCXO. 0: PB0 selected; 1: VDDTCXO selected.
In addition, the voltage to apply depends on TCXO selected. Also, in that case, you’ll have a static power consumption, even when 32MHz is not needed.
2- No, table 28/29 are based on a XO oscillator. Add 1.5mA (when 32MHz runs) if TCXO is used.
3- This is an LDO, with a programmable voltage.
Best Regards.
STTwo-32
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2024-09-22 08:47 PM
Hi ,
you mentioned I need to add 1.5mA due to the TCXO consumption.
1. Do you assume that the external TCXO requires 1.5mA and thats the reason you mention 1.5mA ?
or , 1.5mA is the additional current required by the STM32 VDD and its in addition to the current required by the exteranl TCXO VDD ?
2. what is the static additional current ,that you mentioned , required by the STM32 VDD when not using the 32Mhz ?
Thank You very much!
Viola
2024-09-24 11:51 PM
Hi ,
Any update regarding those issues?
Thank you,
Viola