  The Topmetal-M is a large area pixel sensor (18 mm * 23 mm) prototype
fabricated in a new 130 nm high-resistivity CMOS process in 2019. It contains
400 rows * 512 columns square pixels with the pitch of 40 {\mu}m. In
Topmetal-M, a novel charge collection method combing the Monolithic Active
Pixel Sensor (MAPS) and the Topmetal sensor has been proposed for the first
time. Both the ionized charge deposited by the particle in the sensor and along
the track over the sensor can be collected. The in-pixel circuit mainly
consists of a low-noise charge sensitive amplifier to establish the signal for
the energy reconstruction, and a discriminator with a Time-to-Amplitude
Converter (TAC) for the Time of Arrival (TOA) measurement. With this mechanism,
the trajectory, particle hit position, energy and arrival time of the particle
can be measured. The analog signal from each pixel is accessible through
time-shared multiplexing over the entire pixel array. This paper will discuss
the design and preliminary test results of the Topmetal-M sensor.
