F103RB vs F105RB

As mentioned before I am a big fan of STM32F105RB as the smallest MCU that I use unless package size is an issue. I have other preferences for LQFP48 and TSSOP20. What puzle me is a comparison between STM32F103RB and STM32F105RB on functionality and prices from AliExpress. I suspect that the reason for the low price on F105RB is because they are ditching old 32Kb Versions since the New Versions have 64Kb (Just guessing)? But, the price difference is only 0.1 USD on ST’s own sites as well. You have a similar game between STM32F103CB and STM32F303CB.

MCU 32 bit ARM M3 32 bit ARM M3
Frequency 72 Mhz 72 Mhz
FLASH 128Kb Flash 128Kb
SRAM 20Kb SRAM 32/64Kb (1)
Package LFPQ64 LFPQ64
PSU 2 – 3.6V 2 – 3.6V
PVD Yes Yes
x-tal 4 – 16 Mhz 3-25Mhz
Internal x-tal 8 Mhz 8 Mhz
Power Sleep, Stop, Standby Sleep, Stop, Standby
ADC 2 x 12 bit, 16 channels 2 x 12 bit, 16 channels
DAC 2 x 12 bit
DMA 7 channels 12 channels
5V Tolerant IO Yes Yes
SWD Yes Yes
Timers 7 10
I2C 2 2
UART 3 5
SPI 2 3
I2S 2 (On SPI)
CAN 1 2
USB 1 1
CRC Yes Yes
Unique ID Yes Yes
Price Ca 2.5 USD Ca 1.6 USD

(1) Current datasheet state 64Kb SRAM, while older datasheet state 32Kb SRAM.

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