公开(公告)号：US09742398B2

公开(公告)日：2017-08-22

申请号：US14994560

申请日：2016-01-13

Applicant: Texas Instruments Incorporated

Inventor： Ramesh Chandrasekaran ,  Cetin Kaya

IPC: H03K17/687

CPC classification number: H03K17/6871 ,  G01R31/00 ,  H03K17/145 ,  H03K2217/0027

Abstract: Current sensing through a power semiconductor device with reduced sensitivity to temperature and process variations. An example arrangement includes a power switch coupled between a voltage input and an output voltage terminal supplying current to a load; a first isolation switch coupled between the voltage input and a first node; a comparator amplifier having a pair of differential inputs coupled to the first node and a second node outputting a voltage in response to the difference at the differential inputs; and a first current source coupled between a positive supply voltage and the first node to output a first current responsive to the voltage output from the comparator amplifier; wherein the first current is proportional to the current through the power switch and a ratio of the on resistance of the power switch and the on resistance of the first isolation switch. Methods and additional arrangements are also disclosed.

公开(公告)号：US20170201251A1

公开(公告)日：2017-07-13

申请号：US14994560

申请日：2016-01-13

Applicant: Texas Instruments Incorporated

Inventor： Ramesh Chandrasekaran ,  Cetin Kaya

IPC: H03K17/687

CPC classification number: H03K17/6871 ,  G01R31/00 ,  H03K17/145 ,  H03K2217/0027

Abstract: Current sensing through a power semiconductor device with reduced sensitivity to temperature and process variations. An example arrangement includes a power switch coupled between a voltage input and an output voltage terminal supplying current to a load; a first isolation switch coupled between the voltage input and a first node; a comparator amplifier having a pair of differential inputs coupled to the first node and a second node outputting a voltage in response to the difference at the differential inputs; and a first current source coupled between a positive supply voltage and the first node to output a first current responsive to the voltage output from the comparator amplifier; wherein the first current is proportional to the current through the power switch and a ratio of the on resistance of the power switch and the on resistance of the first isolation switch. Methods and additional arrangements are also disclosed.