Texas Instruments Incorporated Deutschland, Gmbh

Jürgen Metzger

Rodney T Burt

Viola Schaffer

An integrated voltage controlled current source device is provided, that extends the high accuracy, low drift output current over a large current range, and provides more headroom and better power efficiency than the standard shunt resistor and INA (instrumentation amplifier) current source arrangement. The device has a control voltage input, a load current output and a current set terminal for a connection of a current set resistor. It contains a selected leg biasing set voltage, corresponding to a control voltage applied to the control voltage input of a regulating driver amplifier providing a regulated voltage to be applied across the current set resistor, thereby causing a reference current to flow through the current set resistor and selected leg(s) of a current mirror. Furthermore, the device contains a dynamically matched current mirror that mirrors the reference current to the load output current. The algorithm for selecting the current mirror legs may be a pseudo-random or a defined pattern.

Voltage controlled current source device

An integrated circuit driver structure, comprising an amplifier, a current mirror block and an external current set resistor, is provided that is digitally configurable to operate in a current output mode or in a voltage output mode with its output level controlled by an external voltage. The current mirror block comprises multiple current sources, all having the same gate bias supplied by the output of amplifier. At any time, at least one current source is connected to supply the reference current to resistor, while all other current sources are connected to mirror the reference current to the load current output towards the load. A current gain ratio is based on the number of current sources connected to supply resistor and the number connected to mirror the reference current.

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Pliezhausen, Germany

Jürgen Metzger