In this paper, a pixel level pulse-frequency-modulation (PFM) ADC was designed for the wide-dynamic-range short infrared focal plane array (IRFPA). When the conventional PFM ADC uses DI to detect weak signal, the injection efficiency will decrease, which result in the loss of the dynamic range. In the designed PFM ADC, the CTIA is used to maintain high efficiency when detecting weak signal. Two levels of gain and self-selected gain technology are used to extend the dynamic range without increasing the power consumption. Self-selected gain technology enables each pixel to choose the gain according to the photocurrent automatically. The circuit was designed and simulated with 0.18μm CMOS process model. The dynamic range is up to 101.5dB, and the power consumption of each pixel is only 10.54μW. A 32×32 pixel level digital readout circuit with the pixel pitch of 50μm was designed based on the proposed PFM ADC.