BQ40Z50: Clock Rising time higher than 1000ns

David David1

Part Number: BQ40Z50

Hi ,

per described in chapter 7.33 Timing requirement:SMBus, tR clokc rise time max < 1000ns, tF fall time <300ns, but i measure it tR of SCLK(47k frequency), it 's always higher than 2us, see it in attachment, then i remove all capacitor and diode connected to SCLK, it's still higher than 2us, do you know why? is it allowed for tR higher than 2us?

Note:tF <=300ns

over 5 years ago

0 David David1 over 5 years ago

Prodigy 130 points

hi,

there is another question on SMBD, the low level can't be pulldown close to zero, the pullup resistor is 2.1k OHM, and two 100 ohm resistors are serial to BQ40Z50(the same as recommended design), why doesn't it pulldown to zero voltage? is there any negative impact?how to improve it?

thanks.