Abstract Spiking Neural Network (SNN) is a type of biologically-inspired neural networks that perform information processing based on discrete-time spikes, different from traditional Artificial Neural Network (ANN). Hardware implementation of SNNs is necessary for achieving high-performance and low-power. We present the Darwin Neural Processing Unit (NPU), a highly-configurable neuromorphic hardware co-processor based on SNN implemented with digital logic, supporting a configurable number of neurons, synapses and synaptic delays. The Darwin NPU was fabricated by standard 180 nm CMOS technology with area size of 5 × 5 mm2 and 70 MHz clock frequency at the worst case. It consumes 0.84 mW/MHz with 1.8 V power supply for typical applications. Two prototype applications are used to demonstrate the performance and efficiency of the Darwin NPU.