TMS320F28035: BQ32002 and 32.768kHz crystal resonator

Wen-Gou Lin

Prodigy 220 points

Part Number: TMS320F28035
Other Parts Discussed in Thread: BQ32002

Below is my circuit (F28035 use I2C pin to communicate to BQ32002), where C36 is a supercapacitor.

After power-on, I can watch 3.3V in VCC pin of BQ32002. But, there is no any signal between OSCI and OSCO pin.

Why does the crystal resonator Y2 not work?

Is my circuit correct?

Any suggestion for me?

over 6 years ago

0 Kevin Allen18 over 6 years ago

TI__Mastermind 45606 points

Hi Wen-Gou,

I am going to move your question to the BQ32002 team's forum as they will be better able to assist you.

Best,

Kevin

0 Lane Boyd over 6 years ago in reply to Kevin Allen18

TI__Genius 16845 points

Hi Wen-Gou,

Does the XTAL meet the specifications of datasheet table 6.3?

Please be aware that the typical ~pF load capacitance of a scope probe is enough capacitance to stop the oscillation of a crystal oscillator circuit. If you probe the OSCO pin, make sure to use a low capacitance probe.

Kind regards,
Lane

C2000™︎ microcontrollers

C2000 microcontrollers forum

TMS320F28035: BQ32002 and 32.768kHz crystal resonator