Research interests

 Main research directions include

(1) Theories and Methods for Intelligent Sensing and Computing

(2) Bio-inspired electronics

(3) Front-end electronics for photon and particle detectors

(4) Radiation-hardened electronics for the instrumentation in radiation environments 

Research and development experiences

 The research group of Professor Gao Wu has been engaged in the research on the design of mixed-signal integrated circuits and radiation-hardened-by-design methodologies of CMOS ASIC/SoC. In the past five years, the team has successively carried out more than 20 projects sponsored by national funds and company cooperation support. The innovative work includes the topologies and design methodologies of front-end readout ASICs for photon and particle radiation sensors, high-precision picosecond time-to-digital converter, pixel readout ASIC for hybrid detectors, neuromorphic hardware accelerators. More than 20 types of ASIC/SoC chips in deep micrometer CMOS technologies have been developed. The chips are applied for the readout electronics of detectors including PMT, SIPM, CZT, Si PIN, APD and SDD and for computer systems for space applications.

Scientific and technological achievements

A 64-channel analog front-end readout ASIC matching CZT pixel detector is developed, as shown in Figure 1. After testing, the equivalent noise charge (ENC) of single readout channel is 66e - + 14e - / PF. The channel inconsistency error is less than 3% and the power consumption is 6 mW / channel. Under irradiation of Am-241 source, the energy spectrum resolution is less than 4.6% (2.7keV, FHWM) @ 59.5keV. The above performance meets the requirements of engineering applications.

Since 2017, a low-noise photon-counting front-end readout ASIC matching Si PIN detector has been developed, as shown in Figure 2. After testing, the input range is 2 ~ 15fC. The power consumption is only 1.25 mW/channel. The best ENC is 60 e- + 4 e- / PF. It can be applied to the readout of Si-PIN detector with large detector capacitance (20 pF). The lower limit of detection energy is 5 keV. The ASIC product has been applied to an electronic personal dosimeter.

“Key techniques and applications of front-end readout electronics chips for photon and particle detector " won the special prize of science and technology in universities of Shaanxi Province in 2021. 

Experimental platform and instrumentation

 At present, four laboratories shown in Figure 3 have been established in the mixed-signal integrated circuits. The labs include an EDA design room of mixed-signal integrated circuits, an electrical testing room, a bare-chip testing room (clean room) and a microcircuit assembly and processing room. The researchers can independently carry out design, packaging, and measurement of mixed-signal chips.

The hardware and software platforms include advanced computing server with EDA software, a high-bandwidth oscilloscope (40GHz),a high-precision oscilloscope (12 bit), a signal generator (40GHz), a logic analyzer, a spectrum analyzer, a LCR tester,network analyzer, a semi-automatic probe, wire-bonding machine, microcircuit processing platform, etc.