MAX3221E: Hardware review_MAX3221ECPWR

Manjunath G14

Expert 2075 points

Part Number: MAX3221E

Hello TI Team,

Please find the attached Schematic of "MAX3221ECPWR" RS232 Transceiver and review the same.

Thanks

0 Eric Hackett over 4 years ago

Manjunath,

Thanks for bringing this to E2E.

With a 3.3V VCC supply, all capacitors for the charge pumps are the correct value (0.1uF).
The bypass capacitor on VCC is also the correct value at 0.1uF.
The EN pin grounded means ROUT will always be fully enabled. I just want to verify that this is the intention.
With FORCEOFF and FORCEON both pulled up, the device will be have normal operation with auto-power down disabled. If this is the intended configuration then these pull-ups are correct.
It's okay to leave INVALID floating, just know that if RIN goes unpowered then the user won't have any indication of this.

Please let me know if you have any other questions.

Regards,

0 Manjunath G14 over 4 years ago in reply to Eric Hackett

Expert 2075 points

Hi Eric,

Thanks for the Quick review comments.

My responses are inlined below

With a 3.3V VCC supply, all capacitors for the charge pumps are the correct value (0.1uF).
- Manjunath : Okay
The bypass capacitor on VCC is also the correct value at 0.1uF.
- Manjunath : Okay
The EN pin grounded means ROUT will always be fully enabled. I just want to verify that this is the intention.
- Manjunath : Yes, This is intentionally done to keep it on.
With FORCEOFF and FORCEON both pulled up, the device will be have normal operation with auto-power down disabled. If this is the intended configuration then these pull-ups are correct.
- Manjunath : Yes this is intenionally done
It's okay to leave INVALID floating, just know that if RIN goes unpowered then the user won't have any indication of this.
Manjunath: Yes, updated now.

Thanks for the Support.

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