  Resonator-based optical frequency comb generation is an enabling technology
for a myriad of applications ranging from communications to precision
spectroscopy. These frequency combs can be generated in nonlinear resonators
driven using either continuous-wave (CW) light, which requires alignment of the
pump frequency with the cavity resonance, or pulsed light, which also mandates
that the pulse repetition rate and cavity free spectral range (FSR) are
carefully matched. Advancements in nanophotonics have ignited interest in
chip-scale optical frequency combs. However, realizing pulse-driven on-chip
Kerr combs remains challenging, as microresonator cavities have limited tuning
range in their FSR and resonance frequency. Here, we take steps to overcome
this limitation and demonstrate broadband frequency comb generation using a
$\chi^{(3)}$ resonator synchronously pumped by a tunable femtosecond pulse
generator with on-chip amplitude and phase modulators. Notably, employing
pulsed pumping overcomes limitations in Kerr comb generation typically seen in
crystalline resonators from stimulated Raman scattering.
