The Nevro Senza Spinal Cord Stimulation (SCS) system ("HF10") operates at 10 kHz, faster than conventional SCS systems, resulting in significantly more power delivered to the tissues. Using a SCS heat phantom and bioheat multi-physics model, we characterized tissue temperature increases by HF10 stimulation. We also analyzed Senza Implanted Pulse Generator (IPG) output waveform including voltage compliance and bandwidth limits with increasing load impedance. A custom high-bandwidth stimulator provided pulses and sinusoidal stimulation for control experiments. Heating of spinal tissues by Senza 10 kHz SCS increased quickly with stimulation level and load impedance, while dampened by IPG pulse bandwidth and compliance limits. Finally, we show Senza IPGs battery life is determined by power deposition to the lead.