Unexpected high voltage seen on VBus.

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peya_3972321
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我的设计参考了这个:https://www.cypress.com/documentation/reference-designs/ccg3pa-car-charger-reference-design-using-so...

当我插入Type-C设备时,CYPD3175总是在sln_pd_event_handler函数里报告这个错误:APP_EVT_UNEXPECTED_VOLTAGE_ON_VBUS

但是实际测量的VBus电压只有5.17V,和CY4532一样,是很正常的电压。

原理图里的R30和Q5只需要选择其中一个即可,两种接法我都尝试了。

当我使用R30时,依然会报这个错误,但是设备可以得到正常的5V供电,只是PD无法正常通信,没办法申请更高的电压。

当我使用Q5时,在Type-C口无法得到电压,不过测量VBus是有5V电压的。

串口每100ms输出一次电压电流信息,app_evt_t信息是实时输出的。

在这块板子上进行插入设备和拔出设备的详细日志如下:

Power: 0W 0mW U: 117mV I: 0mA

Power: 0W 0mW U: 117mV I: 0mA

0x21: Type-C AttachWait state entered.

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 0mW U: 5117mV I: 0mA

0x00: Unexpected high voltage seen on VBus.

Power: 0W 0mW U: 5117mV I: 0mA

Power: 0W 204mW U: 5117mV I: 40mA

Power: 0W 204mW U: 5117mV I: 40mA

Power: 0W 204mW U: 5117mV I: 40mA

Power: 0W 0mW U: 5117mV I: 0mA

Power: 0W 204mW U: 5117mV I: 40mA

Power: 0W 204mW U: 5117mV I: 40mA

Power: 0W 0mW U: 5117mV I: 0mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 204mW U: 5117mV I: 40mA

Power: 0W 204mW U: 5117mV I: 40mA

Power: 0W 0mW U: 5117mV I: 0mA

Power: 0W 204mW U: 5117mV I: 40mA

Power: 0W 204mW U: 5117mV I: 40mA

Power: 0W 409mW U: 5117mV I: 80mA

0x22: Type-C transition from AttachWait to Unattached.

Power: 0W 403mW U: 5039mV I: 80mA

Power: 0W 393mW U: 4921mV I: 80mA

Power: 0W 384mW U: 4804mV I: 80mA

Power: 0W 374mW U: 4687mV I: 80mA

Power: 0W 365mW U: 4570mV I: 80mA

Power: 0W 359mW U: 4492mV I: 80mA

Power: 0W 350mW U: 4375mV I: 80mA

Power: 0W 343mW U: 4296mV I: 80mA

Power: 0W 337mW U: 4218mV I: 80mA

Power: 0W 331mW U: 4140mV I: 80mA

Power: 0W 324mW U: 4062mV I: 80mA

CY4532设备上正确的日志如下:

Power: 0W 0mW U: 39mV I: 0mA

Power: 0W 0mW U: 39mV I: 0mA

0x21: Type-C AttachWait state entered.

Power: 0W 0mW U: 273mV I: 0mA

Power: 0W 0mW U: 234mV I: 0mA

0x23: Type-C attach event.

0x02: Type-C connect detected.

0x0C: New PD message received.

0x04: Cable (EMCA) discovery successful.

0x28: Sink device connected.

0x0C: New PD message received.

Power: 0W 0mW U: 5117mV I: 0mA

0x16: Contract negotiation completed.

PDO: 15W  5V  3000mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 358mW U: 5117mV I: 70mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 358mW U: 5117mV I: 70mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

0x03: Type-C disconnect(detach) detected.

Power: 0W 0mW U: 0mV I: 0mA

Power: 0W 0mW U: 39mV I: 0mA

Power: 0W 0mW U: 39mV I: 0mA

如何解决这个“Unexpected high voltage seen on VBus.”呢?

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1 Solution
ShifangZ_26
Moderator
Moderator
Moderator
10 likes given 250 sign-ins 1000 replies posted

Hi ,

您这设计的问题是:在Type-C口没有插入之前在VBUS上已经检测到5V的电压。这是与Type-C Safe0V的理论不符合的。根据您提供的电路设计,您需要将硬件修改:将VBUS_C_MON于VBUS断开,VBUS与Type_C_VBUS断开,然后接VBUS_C_MON与Type_C_VBUS即可。

pastedImage_0.png

Best Regards,

Lisa

View solution in original post

4 Replies
ShifangZ_26
Moderator
Moderator
Moderator
10 likes given 250 sign-ins 1000 replies posted

Hi ,

您这设计的问题是:在Type-C口没有插入之前在VBUS上已经检测到5V的电压。这是与Type-C Safe0V的理论不符合的。根据您提供的电路设计,您需要将硬件修改:将VBUS_C_MON于VBUS断开,VBUS与Type_C_VBUS断开,然后接VBUS_C_MON与Type_C_VBUS即可。

pastedImage_0.png

Best Regards,

Lisa

谢谢你的回答,很有帮助,我会按照这个建议进行修改。

我还有一个疑问,在CY4532上,我可以通过连接J3的2-3来复现这个设计错误,但是CY4532可以正常工作,我不明白。

按10ms记录的日志如下,可以看到 Type-C AttachWait 以后,立即检测到了比较高的4417mV,然后很快就降到了195mV,不会报高电压错误:

Power: 0W 0mW U: 273mV I: 0mA

Power: 0W 0mW U: 273mV I: 0mA

0x21: Type-C AttachWait state entered.

Power: 0W 0mW U: 4414mV I: 0mA

Power: 0W 0mW U: 234mV I: 0mA

Power: 0W 0mW U: 195mV I: 0mA

Power: 0W 0mW U: 195mV I: 0mA

Power: 0W 0mW U: 195mV I: 0mA

Power: 0W 0mW U: 195mV I: 0mA

Power: 0W 0mW U: 195mV I: 0mA

Power: 0W 0mW U: 195mV I: 0mA

Power: 0W 0mW U: 195mV I: 0mA

Power: 0W 0mW U: 195mV I: 0mA

Power: 0W 0mW U: 195mV I: 0mA

Power: 0W 0mW U: 195mV I: 0mA

Power: 0W 0mW U: 195mV I: 0mA

Power: 0W 0mW U: 195mV I: 0mA

0x23: Type-C attach event.

0x02: Type-C connect detected.

Power: 0W 0mW U: 5117mV I: 0mA

Power: 0W 0mW U: 5117mV I: 0mA

Power: 0W 0mW U: 5117mV I: 0mA

Power: 0W 0mW U: 5117mV I: 0mA

Power: 0W 0mW U: 5117mV I: 0mA

Power: 0W 204mW U: 5117mV I: 40mA

Power: 0W 409mW U: 5117mV I: 80mA

0x28: Sink device connected.

0x0C: New PD message received.

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

0x16: Contract negotiation completed.

Power: 0W 409mW U: 5117mV I: 80mA

PDO: 15W  5V  3000mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

Power: 0W 409mW U: 5117mV I: 80mA

0x03: Type-C disconnect(detach) detected.

Power: 0W 0mW U: 4726mV I: 0mA

Power: 0W 0mW U: 3164mV I: 0mA

Power: 0W 0mW U: 2226mV I: 0mA

Power: 0W 0mW U: 1601mV I: 0mA

Power: 0W 0mW U: 1171mV I: 0mA

Power: 0W 0mW U: 859mV I: 0mA

Power: 0W 0mW U: 585mV I: 0mA

Power: 0W 0mW U: 429mV I: 0mA

Power: 0W 0mW U: 429mV I: 0mA

Power: 0W 0mW U: 429mV I: 0mA

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Hi

您设计的固件使用的是CY4532的固件吗?固件的设计是可以调节。您可以使用Cypress最新的固件,来达到不修改硬件便达到这个效果。但是这样是不推荐的。因为如果您设计的是POWER SOURCE,在没有任何Type-C设备插入之前给VBUS,是不符合规范的。

SDK: https://www.cypress.com/documentation/software-and-drivers/ez-pd-ccgx-power-software-development-kit

Best Regards,

Lisa

0 Likes

好的,我会按照正确的规范进行设计,感谢您的回答。

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