Abstract: In order to meet the needs of low-cost, high integration space instruments for space power systems, a space-based instrument C8051F040 chip power controller was designed. The major difference between the controller and the traditional design approach is the use of highly integrated lithium-ion battery controller chip (bq77PL900) as an integrated controller chip instead of analog circuits. By employing the bq77PL900, the size of power controller is reduced and the energy of the power controller used is decreased, and the anti-jamming ability of the system is enhanced. To improve the reliability of the system, the system uses the online EEPROM re-injection technology, which can be used to discover the knocked data. This experiment proves that this design not only greatly simple and reliable, but also enhance the efficiency of the system by 5%. This design can wildly used in low-cost space instruments and small satellites.