Catalog

1. Type C Interface design

2.  Power circuit

 3. burn

1. Type C Interface design

because CH549G I won't support it USB3.0, So just use 12pin Of Type-C Interface . about CH549G Of PD function , I really don't understand , The routine also calls the Library , It seems to be realized by software CC communication , I was going to try Sink Mode will VBUS Adjust to above 5V Look at the effect , On the hardware , If you are free, see if the software can be implemented .

VBUS It's voltage detection , Don't pick up Pin4,CC1 and CC2 Separate with resistance , need PD Connect verification .

2.  Power circuit

CH549G Support 3.3V and 5V, namely VDD foot （Pin15） Can connect 3.3V and 5V, and V33 foot （Pin16） Is constant 3.3V, If VDD Pick up 5V, be V33 Use the inside LDO Output 3.3V, There should be one outside 0.1uF The capacitance of . This power supply can only be used internally USB Use , Cannot be used for external power . That's it. 2 In this case ：

        When VDD Pick up 5V when , No external is required 3.3V,

        When VDD Pick up 3.3V when , External 3.3V Supply voltage to V33 foot .

consider PD Output above 5V The situation of , use 0 Ohm resistance separation VBUS To 5V.

Select by jumper 5V or 3.3V：1 and 3 Short circuit of feet indicates 5V;3 and 5、2 and 4 Short circuit means 3.3V. If jumpers are needed in actual projects 5V or 3.3V, In fact, only 1-3 and 3-5 Short circuit method , And will be 2-4 Always short circuited , namely V33 foot （Pin16） Always from the outside 3.3V Just supply power .

 CH549 The power part of the terminal is shown in the figure below ,C5 and C6 As close as possible CH549.

 3. burn

CH549 Support 2 A burning method ： A serial port 0 and USB,2 Both ways of burning need P51（ namely DP foot , By default ） Pull it up and power it on .