Many experimental efforts have been devoted to searching for dark photon dark matter. However, the currently known production mechanisms face various difficulties, including a limited dark photon mass range. It is therefore of interest to explore alternative sources of dark photons with broader mass ranges. We propose a new production mechanism via tachyonic instability- the exponential growth of dark photons resulting from an axion-like particle’s coherent oscillation. We demonstrate viable cosmological histories for dark photon dark matter with masses down to 10^-6 eV. We also discuss the collider and direct detection signatures of the Peccei-Quinn charged fermions and dark photons respectively.