| As a green,high speed and high precision additive manufacturing technology,3D?Three Dimesion?printing plays a significant role in textile,ceramics,electronics and medical.As the execution unit of 3D printing,3D printhead is the core of printing systems.The conventional 3D printhead driver has a problem that its driving capability decays as temperature rises.As a result,the printhead suffers a severe performance degration for the dissatisfaction with 3D printhead's current threshold.Thereby it's necessary to realize the temperature adaption of3D printhead driver to improve 3D printhead's performance.Based on the operational principle of 3D printhead,it's analyzed how printhead's performance and lifetime are influenced by the relative relation between its current threshold and driving current.On this basis,a temperature adaptive driver is developed in this thesis,consisting of output stage module,temperature detection module and reference voltage module.The ouput stage module can be divided into main and subsidiary power transistors.The temperature detection module monitors main power transistors'temperature to generate temperature detection voltage Vtemp,which is compared with Vrefef from the reference voltage module.When main power transistors'temperature is higher than the predefined temperature threshold T1,the driver automatically enables the branch of subsidiary power transistors and compensates output stage's current capability,keeping the driving current higher than printhead's current threshold.The layout of the driving circuit has been accomplished and validated with 1?m 40V technology.The post layout simulation results state that the driving current is higher than printhead's current threshold as temperature rises from 0?to 100?with an average driving current around 45.61mA.With the quiescent current under 100?A,the offset of the driving current is less than 2.26%,while its standard deviation is reduced to 1.13%.In conclusion,the driver's temperature adaption is realized. |
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