Programmable voltage generator

Programmable voltage generator comprising:

• a differential amplifier having a positive input terminal, a negative input terminal and an output terminal;
• a reference voltage, tied to said positive input;
• a feedback node tied to said negative input terminal;
• a feedback resistor tied at one end to said feedback node and tied at the other end to a common ground;
• a programmable resistive element tied at one end to said feedback node and tied at the other end to said output terminal;
• a control means;
• said programmable resistive element comprising:
• a plurality of resistors linked in series, a resistor node between each adjacent pair of resistors;
• said series of resistors tied at one end to said feedback node, and at the other end to the output terminal;
• a plurality of switches, each switch directly connected at a first conduction terminal to said output terminal and at a second conduction terminal to an individual one of said resistor nodes;
• said plurality of switches controlled by said control means, such that switches not selected by said control means remain open, while a selected switch closes a circuit between it's respective resistor node and said output terminal;
• and
• an additional switch interposed between the output terminal and a first one of the plurality of resistors, the additional switch being controlled by the control means as one of the plurality of switches said control means configured to vary a total resistance between the output terminal and the common ground by selectively closing one of the plurality of switches.

Programmable voltage generator comprising:

• a negative feedback element;
• a programmable resistive divider;
• control means,
• said feedback element having a first and a second input terminal, and an output terminal, said first input terminal receiving a reference quantity,
• said programmable resistive divider having a feedback node connected to said second input terminal and comprising a feedback resistor interposed between a line at reference potential and said feedback node and a programmable resistor interposed between said feedback node and said output terminal,
• said programmable resistor comprising a plurality of resistive elements and a plurality of controlled switch elements, said resistive elements disposed reciprocally in series between said output terminal and said feedback node and defining between them a plurality of intermediate nodes;
• said controlled switch elements interposed between said output terminal and a respective intermediate node,
• said control means suitable for selectively controlling the closure of said controlled switch elements;
• and
• a dummy switch disposed in series with said feedback resistor.

Programmable voltage generator comprising:

• a differential amplifier having a positive input terminal, a negative input terminal and an output terminal;
• a reference voltage, tied to said positive input;
• a feedback node tied to said negative input terminal;
• a feedback resistor tied at one end to said feedback node and tied at the other end to a common ground;
• a programmable resistive element tied at one end to said feedback node and tied at the other end to said output terminal;
• a control means;
• said programmable resistive element comprising:
• a plurality of resistors linked in series, a resistor node between each adjacent pair of resistors;
• said series of resistors tied at one end to said feedback node, and at the other end to the output terminal;
• a plurality of switches, each switch directly connected at a first conduction terminal to said output terminal and at a second conduction terminal to an individual one of said resistor nodes;
• said plurality of switches controlled by said control means, such that switches not selected by said control means remain open, while a selected switch closes a circuit between it's respective resistor node and said output terminal;
• said control means configured to vary a total resistance between the output terminal and the common ground by selectively closing one of the plurality of switches wherein each of said plurality of switches has the same resistive value;
• and a dummy switch, in series with said feedback resistor, of a resistive value to compensate for the resistive value of one of said plurality of switches.

A Programmable voltage generator comprising:

• a negative feedback element;
• a programmable resistive divider;
• and
• control means,
• said feedback element having a first and a second input terminal, and an output terminal coupled to an output node, said first input terminal receiving a reference quantity,
• said programmable resistive divider having a feedback node connected to said second input terminal and comprising a feedback resistor interposed between a line at reference potential and said feedback node and a programmable resistor interposed between said feedback node and said output node,
• said programmable resistor comprising a plurality of resistive elements and a plurality of controlled switch elements, said resistive elements disposed reciprocally in series between said output node and said feedback node and defining between them a plurality of intermediate nodes;
• each of said controlled switch elements directly connected between said output node and a respective intermediate node,
• said programmable resistive divider further comprising a circuit network disposed between said feedback node and one of said resistive elements, said circuit network comprising a plurality of branches connected together in parallel, each branch including a parallel resistor and a parallel switch which are disposed in series with each other, and
• said control means suitable for varying a total resistance between the output node and the line at reference potential by selectively controlling the closure of one of said controlled switch elements.