PSoC1 USB D+ pullup

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cross mob
stsm_296211
Level 2
Level 2
10 replies posted 5 replies posted 5 questions asked

I'm using the CY8C24894-24LTXI on a board mainly as a simple USB interface to the outside world (which can be both windows or embedded hosts). The PSoC1 is always a device. I recently have enumeration problems that pop up. In looking closer at the PSoC1 side, the D+ pullup measures much higher than the spec 1.5K, closer to 2k. This appears to add to the startup issues. There's not much in the Developer's USB wizard that I can see would bias the D+ pullup value.

Has anyone seen this issue, or any tips on what we might be doing on startup that would effect the D+ pullup? This is not a new board (like over 10 years), so nothing has changed in years.

Thanks - Steve

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SampathS_11
Moderator
Moderator
Moderator
250 sign-ins 250 solutions authored 5 questions asked

Hello Steve,

Kindly adhere to the spec 1.5K. Moving away from this spec will result in a different logic level which may not be recognized by the host.

Best regards,

Sampath Selvaraj

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SampathS_11
Moderator
Moderator
Moderator
250 sign-ins 250 solutions authored 5 questions asked

Hello Steve,

Kindly adhere to the spec 1.5K. Moving away from this spec will result in a different logic level which may not be recognized by the host.

Best regards,

Sampath Selvaraj

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