How does Qualcomm Quick Charge sense the presence on another compatible device. Isit looking for voltahe on certain USB pins?
Qualcomm Quick Charge detecting compatible devices
Started by ●June 25, 2022
Reply by ●June 25, 20222022-06-25
On Saturday, 25 June 2022 at 22:41:38 UTC+2, Pamela wrote:> How does Qualcomm Quick Charge sense the presence on another compatible > device. > > Isit looking for voltahe on certain USB pins?quick charge devices detect higher charging voltage and accept higher voltage since current is limited by diameter of the wire/s in the charging cable and by internal circuit board.
Reply by ●June 25, 20222022-06-25
In article <XnsAEC1DC911997C37B93@88.198.57.247>, Pamela <pamela.private.mailbox@gmail.com> wrote:>How does Qualcomm Quick Charge sense the presence on another compatible >device. > >Isit looking for voltahe on certain USB pins?Basically, yes. There's a whole negotiation process which takes place between the device, and the dedicated charging port. Take a look at the data sheet for the On Semiconductor NCP4371 for some of the details.
Reply by ●June 25, 20222022-06-25
søndag den 26. juni 2022 kl. 00.07.44 UTC+2 skrev Dave Platt:> In article <XnsAEC1DC9...@88.198.57.247>, > Pamela <pamela.priv...@gmail.com> wrote: > >How does Qualcomm Quick Charge sense the presence on another compatible > >device. > > > >Isit looking for voltahe on certain USB pins? > Basically, yes. There's a whole negotiation process which takes place > between the device, and the dedicated charging port. Take a look at > the data sheet for the On Semiconductor NCP4371 for some of the > details.and QC4 now also supports USB-PD over USB-C I assume in preperation for the EU mandate that phones/tablets etc. must charge via USB-C, and support USB-PD if the higher power is needed
Reply by ●June 26, 20222022-06-26
On 23:07 25 Jun 2022, Dave Platt said:> In article <XnsAEC1DC911997C37B93@88.198.57.247>, > Pamela <pamela.private.mailbox@gmail.com> wrote: >> >>How does Qualcomm Quick Charge sense the presence on another compatible >>device. >> >>Is it looking for voltage on certain USB pins? > > Basically, yes. There's a whole negotiation process which takes place > between the device, and the dedicated charging port. Take a look at > the data sheet for the On Semiconductor NCP4371 for some of the > details.I found it here. https://www.onsemi.com/pdf/datasheet/ncp4371-d.pdf It looks rather complicated to me but it seems there's some suprisingly elaborate signalling involved. Figure 20 seems to suggest that 2 if not 3 leads get utilised for signalling.
