In this paper, a Pixelated Residual Gas Ionization Profile Monitor (RGIPM) has been proposed for the 320 kV High-Voltage Platform at the Institute of Modern Physics, Chinese Academy of Sciences. Beam profile monitoring in both the horizontal and vertical directions is realized in one-meter length. A compact microchannel plate (MCP) detector with an array of the Topmetal-II${}^{-}$ pixel ASIC as the anode is proposed for the device. The spatial resolution of the detector is expected to be comparable to the intrinsic pixel size of the anode. Compensation electric and magnetic fields have been integrated into the RGIPM to minimize the influence of the measurement fields on the transportation of low energy ion beams. This paper presents the test results of a prototype of the MCP detector and the study on the electric and magnetic fields.