Patent Number: 6,294,947

Title: Asymmetrical current steering output driver with compact dimensions

Abstract: A current output circuit with two output nodes connectable to a load and providing a plurality of discretely selectable current output magnitudes is provided. The circuit consists of a current driver attached across the output nodes supplying a particular current and one or more bypass resistors connected in parallel with the output nodes that can be switched between a non-conducting state and a resistive conducting state. When a load is connected across said output nodes, the particular magnitude of current sourced through the load can be selected by switching the state of the bypass resistors. The magnitude of the bypass resistors is preselected to provide several discretely selectable states of output current of substantial equal steps. The current driver can be combined with a current switch to increase the number of output states. Several current drivers with current switches may be provided and the bypass resistors integrated into the current switch itself.

Inventors: Gabara; Thaddeus John (Murray Hill, NJ)

Assignee: Agere Systems Guradian Corp.

International Classification: H03K 19/003 (20060101); H03K 17/693 (20060101); H03K 19/0175 (20060101); H03K 17/687 (20060101); H03K 017/62 ()

Expiration Date: 09/25/2018