How much heat is needed to break CO2 down to CO?

I have found that because the oxygen is double bonded to carbon, it takes about $\mathrm{1500\ ^\circ C}$ to break it down from $\ce{CO2}$ to $\ce{C}$ and $\ce{O}$. But, I am curious, would it take less heat energy to break $\ce{CO2}$ down to $\ce{CO}$ and $\ce{O}$?

Heating CO2 at atmospheric pressure:

At 1000K it is still essentially all CO2.

At 2000K: 98% CO2, 1.4% CO, 0.7% O2

At 3000K: 44% CO2, 36% CO, 16% O2, 4% O

At 5000K: 50% CO, 50% O

only at even higher temperature does significant atomic C appear (9% at 6000K).

See Thermal decomposition of carbon dioxide in an argon plasma jet for more information.