lhlbluesky_lhl
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i have designed a bandgap in 0.18um 0.33V process, which is the classic structure (an opamp, two bjt of 1:8, a pmos pair, and a resistor), VREF=VEB+VT*ln8/R1*R2, but the tc is 45ppm for the simulation. i used some methods to improve the tc, such as exp compensation, different type of resistors (different tc, one is positive, one is negative), and so on, but it only improves a little. in some papers, i see the compensated bandgap can have a tc of 5ppm or below, but how to achive this in actual case? or how to do curvature compensation for bandgap in real project design?
thanks all in advance.
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