In this article, a low-power, radiation-hard front-end circuit for monolithic pixel sensors, designed to meet the requirements of low noise and low pixel-to-pixel variability, the key features to achieve high detection efficiencies, is presented. The sensor features a small collection electrode to achieve a small capacitance (<5 fF) and allows full CMOS in-pixel circuitry. The circuit is implemented in the 180-nm CMOS imaging technology from the TowerJazz foundry and integrated into the MALTA2 chip, which is part of a development that targets the specifications of the outer pixel layer of the ATLAS Inner Tracker upgrade at the LHC. One of the main challenges for monolithic sensors is a radiation hardness up to 10 15 1-MeV <inline-formula> <tex-math notation="LaTeX">\text {n}_{\text {eq}}/\text {cm}^{{2}} </tex-math></inline-formula> non-ionizing energy loss (NIEL) and 80 Mrad total ionizing dose (TID) required for this application. Tests up to <inline-formula> <tex-math notation="LaTeX">{3} \cdot {10}^{15} </tex-math></inline-formula> 1-MeV <inline-formula> <tex-math notation="LaTeX">\text {n}_{\text {eq}}/\text {cm}^{{2}} </tex-math></inline-formula> and 100 Mrad were performed on the MALTA2 sensor and front-end circuit, which still show good performance even after these levels of irradiation, promising for even more demanding applications such as the future experiments at the high-luminosity large hadron collider (HL-LHC).