Abstract: A method of varying the gain of an amplifier and an amplifier array are provided. The amplifier array includes two or more amplifier stages (201, 202) connected in parallel with each amplifier stage having a gain control means. Input signal means (203, 204) are provided for each amplifier stage with the input signals of the amplifier stages being of different amplitude. Means for enabling and disabling an amplifier stage (216) are provided and means for summing the outputs of the enabled amplifier stages obtain an output signal (212).

Abstract: Described is a system for trimming the value of an electronic component. The system comprises: at least one trimming component, each trimming component having an associated switch for selectively connecting that trimming component to the electronic component in response to a corresponding bit in a control vector. A comparator is included for generating an output bit having a first value if a net value of the electronic component and any connected trimming components differs from a desired value. A controller connected to the switches and the comparator generates the control vector in dependence on the output of comparator, the controller comprising a shift register for sequentially receiving successive output bits from the comparator; wherein the control vector comprises the contents of the shift register and wherein a bit of said first value in control vector effects switching of the corresponding switch.

Abstract: A method of varying the gain of an amplifier and an amplifier array are provided. The amplifier array includes two or more amplifier stages (201, 202) connected in parallel with each amplifier stage having a gain control means. Input signal means (203, 204) are provided for each amplifier stage with the input signals of the amplifier stages being of different amplitude. Means for enabling and disabling an amplifier stage (216) are provided and means for summing the outputs of the enabled amplifier stages obtain an output signal (212).

Abstract: Described is a system for trimming the value of an electronic component. The system comprises: at least one trimming component, each trimming component having an associated switch for selectively connecting that trimming component to the electronic component in response to a corresponding bit in a control vector. A comparator is included for generating an output bit having a first value if a net value of the electronic component and any connected trimming components differs from a desired value. A controller connected to the switches and the comparator generates the control vector in dependence on the output of comparator, the controller comprising a shift register for sequentially receiving successive output bits from the comparator; wherein the control vector comprises the contents of the shift register and wherein a bit of said first value in control vector effects switching of the corresponding switch.