Circuit and method for performing arithmetic operations on current signals
First Claim
Patent Images
1. Circuit comprising an input means configured to selectively receive a current from a plurality of currents;
- a first current mirror with mirror ratio m;
a second current mirror;
a third current mirror;
a cross-multiplexer;
a differential capacitive transimpedance amplifier havinga first capacitance and a first switching element connected in parallel to a negative input port and a first output port of the differential capacitive transimpedance amplifier anda second capacitance and second switching element connected in parallel to a positive input port and a second output port of the differential capacitive transimpedance amplifier;
the input means being connected to an input port of the first current mirror;
an output port of the first current mirror being connected to input ports of the second and third current mirror;
an output port of the second current mirror being connected to a first input port of the cross-multiplexer;
an output port of the third current mirror being connected to a second input port of the cross-multiplexer;
a first output port of the cross-multiplexer being connected to the negative input port of the differential capacitive transimpedance amplifier and a second output port of the cross-multiplexer being connected to the positive input port of the differential capacitive transimpedance amplifier;
the cross-multiplexer being configuredeither to establish a first current path between its first input port and its first output port and a second current path between its second input port and its second output port in direct modeor to establish a first current path between its first input port and its second output port and a second current path between its second input port and its first output port in reverse mode.
2 Assignments
0 Petitions
Accused Products
Abstract
A circuit for performing arithmetic operations includes a differential capacitive transimpedance amplifier (CTIA) and a cross-multiplexer. The cross multiplexer forwards the current to be integrated out of a plurality of current sources either to the positive input port of the differential CTIA for positive integration in direct mode or to the negative input port of the differential CTIA for negative integration in reverse mode.
6 Citations
10 Claims
-
1. Circuit comprising an input means configured to selectively receive a current from a plurality of currents;
- a first current mirror with mirror ratio m;
a second current mirror;
a third current mirror;
a cross-multiplexer;
a differential capacitive transimpedance amplifier havinga first capacitance and a first switching element connected in parallel to a negative input port and a first output port of the differential capacitive transimpedance amplifier and a second capacitance and second switching element connected in parallel to a positive input port and a second output port of the differential capacitive transimpedance amplifier; the input means being connected to an input port of the first current mirror; an output port of the first current mirror being connected to input ports of the second and third current mirror; an output port of the second current mirror being connected to a first input port of the cross-multiplexer;
an output port of the third current mirror being connected to a second input port of the cross-multiplexer;a first output port of the cross-multiplexer being connected to the negative input port of the differential capacitive transimpedance amplifier and a second output port of the cross-multiplexer being connected to the positive input port of the differential capacitive transimpedance amplifier; the cross-multiplexer being configured either to establish a first current path between its first input port and its first output port and a second current path between its second input port and its second output port in direct mode or to establish a first current path between its first input port and its second output port and a second current path between its second input port and its first output port in reverse mode. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
- a first current mirror with mirror ratio m;
Specification