| 摘要 |
PROBLEM TO BE SOLVED: To provide a signal clipping circuit that clips an input signal to a level corresponding to an adjusted power supply voltage. SOLUTION: The clipping circuit 20 has a current mirror formation having a reference transistor(TR) 30 and a mirror transistor (TR) 32. The drain of the mirror TR 32 receives an input signal (BDATA) and the source of the mirror TR 32 provides an output signal (CLPBDATA). The reference TR 30 receives a bias current IBIAS. The mirror TR 32 reflects the bias current IBIAS to limit pull-up drive of the mirror TR 32 in the case of pulling up the output signal (CLPBDATA). A disclosed embodiment for clipping circuits 20, 20',20" has a current source 29 to produce the DC bias current IBIAS and has a charge pump 34 to produce a transiting bias current (IPUMP).
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