LMK61PD0A2: Reference Pro Schematic and Output Power

Dylan g

Part Number: LMK61PD0A2

Is there an available schematic for the reference pro board? I want to see the circuitry schematic on the LMK61PDOA2, so I can get an idea of the voltage rails on the LVPECL signals

Also, what is the estimated output power for the LVPECL clock running at 100MHz? Using a scope I can see a 1.35Vpp sine wave (I don't have access to a power meter at the moment)

over 3 years ago

+1 Noel Fung over 3 years ago

TI__Guru* 92090 points

Hi Dylan,

The Altium design file is available in here: https://www.ti.com/lit/zip/snar037

In cases you don't have Altium, below are the power supply and LMK circuitry.

This is the 100MHz LVPECL clock from Ref PRO.

0 Dylan g over 3 years ago in reply to Noel Fung

Prodigy 170 points

Thank you Noel

Your scope capture appears to be showing a 0.8Vpp wave, however when I use a single ended output (OUTP) on my ref pro I see a 1.35Vpp wave (LVDS and HCSL show 600mV and 1.2V peak-to-peak voltage, respectively)

Do you know why that might be?

0 Noel Fung over 3 years ago in reply to Dylan g

TI__Guru* 92090 points

Hi Dylan,

Did you setup your probe to be 50Ω instead of the default of 1MΩ?

0 Dylan g over 3 years ago in reply to Noel Fung

Prodigy 170 points

I was using a 1x BNC to SMA cable for that, can't remember exactly what my impedance was

Plugged it into a spectrum analyzer though and got an output power of ~5.5dBm, which is the measurement I was looking for

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LMK61PD0A2: Reference Pro Schematic and Output Power