公开(公告)号：EP3011756A1

公开(公告)日：2016-04-27

申请号：EP14813271.5

申请日：2014-06-18

申请人： Texas Instruments Incorporated

发明人： ELWART, David H. ,  VINAY, Vikas Suma ,  GRAVES, Christopher M. ,  HAROUN, Baher S.

IPC分类号： H04R3/00 ,  H02H9/04

CPC分类号： H03F1/305 ,  H02H9/045 ,  H03F1/523 ,  H03F3/187 ,  H03F3/68 ,  H03F2200/441 ,  H03F2200/444 ,  H03F2200/555 ,  H03K17/6874 ,  H03K2217/0018

摘要： In described examples, a charge pump (2) is powered by a first reference voltage (VDD) and produces a control voltage signal (VCP) on a control conductor (3). A ground switch circuit (15) includes a depletion mode transistor (MP 1) having a well region (4-1), a source coupled to an output conductor (6- 1), a gate coupled to receive the control voltage signal (VCP), and a drain coupled to a second reference voltage (GND). A protection circuit (17- 1) includes first and second depletion mode protection transistors (MP3- 1, MP4- 1), which have respective gates coupled to the control voltage signal (VCP) and have respective sources coupled to each other. The first depletion mode protection transistor (MP3- 1) has a drain coupled to the well region (4-1), and the second depletion mode protection transistor (MP4- 1) has a drain coupled to an output signal (VQUTI) on the output conductor (6- 1).