用于Flash型FPGA的电流读出电路

Current Readout Circuit for Flash-Based FPGA

为了提高Flash型FPGA中的Flash开关单元在编程后驱动能力的一致性,基于0.11μm2P8M Flash工艺,设计了一款用于读取Flash开关单元驱动电流的读出电路。该驱动电流的读出电路采用与压控电流源进行多点比较的方式,能够实现对Flash开关单元驱动电流的精确测量,保证了Flash开关单元在编程后阈值电压分布的一致性,为Flash型FPGA的优越的可编程性提供了高精度的延迟参数,将Flash开关单元驱动电流的差异控制在5%之内,满足了Flash型FPGA对Flash开关单元的技术要求。仿真结果表明,在电流为20~40μA的范围内,该驱动电流的读出电路有很高的精度和线性度,读取误差小于1μA。

In order to improve the consistency of driving abilities of Flash switch units in Flash-based FPGA after programming,a readout circuit for reading the drive current of Flash switch unit is designed based on 0.11μm 2P8M Flash process.The readout circuit of the drive current adopts the method of multi-point comparison with a voltage controlled current source,which can realize the accurate measurement of the drive current of Flash switch unit,ensure the consistency of threshold voltage distributions of Flash switch units after programming,and provide high precision delay parameters for the superior programmability of Flash-based FPGA.The differences of drive currents of Flash switch units are controlled within 5%,which meet the technical requirements of Flash-based FPGA for Flash switch units.The simulation results show that the readout circuit has high accuracy and linearity in the current range of 20-40μA,and the reading error is less than 1μA.