US 6,982,559 B2 | ||
Accurate and efficient sensing circuit and method for bi-directional signals | ||
John P. Taylor, San Diego, Calif. (US) | ||
Assigned to Kyocera Wireless Corp., San Diego, Calif. (US) | ||
Filed on Jan. 14, 2004, as Appl. No. 10/757,902. | ||
Prior Publication US 2005/0151543 A1, Jul. 14, 2005 | ||
Int. Cl. G01R 27/02 (2006.01); H04B 1/04 (2006.01) |
U.S. Cl. 324—609 | 20 Claims |
14. A mobile communication device comprising:
a transceiver for transmitting and receiving an RF signal;
a mobile power source coupled to the transceiver for supplying power to the transceiver;
a resistive element coupled in series between the mobile communication device and one of the mobile power source and ground;
a sampling unit switchably coupled to the resistive element, the sampling unit configured to sample a voltage across the resistive
element during a sampling mode; and
a charge transfer unit switchably coupling a first input of an amplifier to the sampling unit, the first input switchably
coupled to a first terminal of the sampling unit when the current flows through the resistive element in a first direction,
the first input switchably coupled to a second terminal of the sampling unit when the current flows through the resistive
element in a second direction opposite the first direction, the charge transfer unit and the amplifier operable to convert
the voltage to a ground-referenced output voltage during a charge transfer mode.
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