i2cやcecは電源OFF時でもHi-zになるように実装しよう
チップ内部でGND接続されていたりすると、結果的にLowドライブになってしまい、バス権を取ってしまいます。
満たすべきDC特性、AC特性は以下です。
■ DC
VOH:2.5V 2.7V 3.3V
VOL:- 0.2V 0.6V
1: CEC pin connected to 3.3V via 27Kohm resistor. VDD=3.3V.
2: CEC pin connected to 3.3V via 3Kohm resistor. VDD=3.3V.
3: CEC pin connected to ground via 150Kohm resistor. VDD=3.3V.
■ AC
tr:- 50uS 250uS
tf - 3uS 50uS
1: CEC pin connected to 3.3V via 27Kohm resistor and external 1500pF capacitor to ground. VDD=3.3V.
2: CEC pin connected to 3.3V via 3Kohm resistor and external 7200pF capacitor to ground. VDD=3.3V.
3: CEC pin connected to external 150pF capacitor to ground. VDD=3.3V.
参照：
http://www.chrontel.com/media/Datasheets/CH7322B%20Datasheet%20Rev1.6.pdf
満たすべきDC特性、AC特性は以下です。
■ DC
VOH:2.5V 2.7V 3.3V
VOL:- 0.2V 0.6V
1: CEC pin connected to 3.3V via 27Kohm resistor. VDD=3.3V.
2: CEC pin connected to 3.3V via 3Kohm resistor. VDD=3.3V.
3: CEC pin connected to ground via 150Kohm resistor. VDD=3.3V.
■ AC
tr:- 50uS 250uS
tf - 3uS 50uS
1: CEC pin connected to 3.3V via 27Kohm resistor and external 1500pF capacitor to ground. VDD=3.3V.
2: CEC pin connected to 3.3V via 3Kohm resistor and external 7200pF capacitor to ground. VDD=3.3V.
3: CEC pin connected to external 150pF capacitor to ground. VDD=3.3V.
参照：
http://www.chrontel.com/media/Datasheets/CH7322B%20Datasheet%20Rev1.6.pdf
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