In neuroscience research the development of the brain and the treatment of diseases like certain forms of epilepsy is analysed with genetic mouse disease models. For the special case of the recording from neonatal mice a custom designed integrated circuit is presented. Neonatal mice are only two to three centimetres large and have a weight of only a few gram. Thus, the recording circuitry has to be very small and light weight. The integrated circuit implements 16 low-area, low-power analogue differential preamplifiers with a bandpass characteristic (0.5 Hz to 10 kHz). A multiplexed structure of 8:1 multiplexer, post amplifier and 10 bit successive approximation register (SAR) analogue-to-digital converter (ADC) digitizes the signals with high resolution. The digital data is transmitted via a Serial Peripheral Interface (SPI). The integrated circuit has been implemented in a 130 nm CMOS technology and has been successfully applied in in-vivo measurements with an adult mouse.