DS110DF111: Invert Output Polarity Question

Jack Zhang

Part Number: DS110DF111

Hello, the DS110DF111 datasheet states that "The DS110DF111 can invert the polarity of the data signals by means of a register write. Writing a 1 to bit 7 of register 0x1f inverts the polarity of the output signal for the selected channel. This can provide additional flexibility in system design and board layout." Does the register write invert both OUTA and OUTB? I require this function in my application involving SFP+ and Ethernet controller. If not, is there a way to perform this? Thank you.

5 months ago

+1 Lucas Wolter 5 months ago

TI__Genius 16680 points

Hi Jack,

Writing channel register 0x1F[7]=1 will only apply to the channel selected. Global register 0xFF should be used to select a target channel for register reads and writes. I suggest reading section 2.3 "Register Types" in the programming guide as this explains how to use register 0xFF to select a target channel.

Best,

Lucas

0 Jack Zhang 5 months ago in reply to Lucas Wolter

Intellectual 480 points

Ok, thanks for guidance. To make sure I am clear, in order to invert the polarity of the OUTA signals, I should write 0x04 to register 0xFF and then write channel register 0x1F[7]=1 (hex 0xD5) and similarly, for OUTB, I should write 0x05 to register 0xFF and then write channel register 0x1F[7]=1 (hex 0xD5), correct?

0 Lucas Wolter 5 months ago in reply to Jack Zhang

TI__Genius 16680 points

Hi Jack,

Yes, that's correct.

Best,

Lucas

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DS110DF111: Invert Output Polarity Question