Function generator for providing pulse width modulation

Claim 2

Control apparatus for providing a train of pulses, the width of the pulses to vary in dependence upon a control signal, the dependence to represent a particular function within a particular range for the control signal, the apparatus having a pulse generator for providing a pulse train and having a variable signal input terminal, the improvement comprising: input means for the pulse generator and connected between a source for the control signal and said terminal and including plural components including a network of interconnected resistances; and a switching circuit connected to be responsive to the output of the pulse generator and providing switching operation in the input means for controlling effective resistance in the input means in direct response as well as in response to the complement of the train of switching pulses to obtain a variation of the transfer function of the input means.

Claim 3

Control apparatus as in claim 1, the control apparatus including a resistance network connected for effective resistance control by the switching means in dependence upon the train of switching pulses, and an integrator connected to receive the control signal as input via the network, the integrator output controlling the pulse generator.

Claim 4

Control apparatus for providing a train of pulses, the width of the pulses to vary in dependence upon a control signal, the dependence to represent a particular function within a particular range for the control signal, the apparatus having a pulse generator for providing a pulse train and having a variable signal input terminal, the improvement comprising: input means for the pulse generator and connected between a source for the control signal and said terminal and including plural components including a network of interconnected resistances; the input means including a first resistor, and two series connected resistors connected across the first resistor; and a switching circuit including electronic switching means connected to be responsive to the output of the pulse generator further connected to effectively short circuit one of the series connected resistors for obtainIng variation of the transfer function of the input means.

Claim 5

Control apparatus for providing a train of pulses, the width of the pulses to vary in dependence upon a control signal, the dependence to represent a particular function within a particular range for the control signal, the apparatus having a pulse generator for providing a pulse train and having a variable signal input terminal, the improvement comprising: input means for the pulse generator and connected between a source for the control signal and said terminal and including plural components including a network of interconnected resistances; the input means including a first resistor, and two series connected resistors connected across the first resistor; and a switching circuit including electronic switching means connected to be responsive to the output of the pulse generator further connected to effectively short circuit one of the series connected resistors for obtainIng variation of the transfer function of the input means.

Claim 6

Apparatus as in claim 3, the control signal being applied to the first resistor at one end, to be modified by the resistances of the resistors, the modified signal effective in the pulse generator.

Claim 7

Apparatus as in claim 3, a biasing voltage being applied to the first resistor, the control signal being fed to additional resistors connected to the three resistors to obtain a combined input effective on the pulse generator.

Claim 8

Control apparatus as in claim 1, the input means including a plurality of first interconnected resistors, connected to receive the control signal, and a plurality of second resistors, connected to receive a biasing signal, the switching means including first means connected for controlling effective resistance of the first interconnected resistors, further including second means connected for controlling effective resistance of the second interconnected resistors, third means for connecting one of the first and second means to be responsive to the pulses of the train, and the other one to be responsive to complementary pulses of the train; and means for connecting the first and second resistors to obtain an input for the pulse generator.

Claim 9

Control apparatus as in claim 6, the input being applied directly to an integrator providing an output as input to the pulse generator, operating for pulse width control to obtain zero input for the integrator.

Claim 10

Control apparatus as in claim 7, the pulse generator including a comparator and a sawtooth generator, the comparator receiving the combined integrator output and sawtooth generator output.

Claim 11

Control apparatus for providing a train of pulses, the width of the pulses to vary in dependence upon a control signal, the dependence to represent a particular function within a particular range for the control signal, the apparatus having a pulse generator for providing a pulse train and having a variable signal input terminal, the improvement comprising: the pulse generator having an output terminal; input means for the pulse generator and connected between a source for the control signal and said input terminal and including plural components including interconnected resistances; and a switching circuit connected to be responsive to the output of the pulse generator and providing switching operation in the input means for variation of the transfer function of the input means; the switching circuit including an inverter connected to the output terminal, a first field effect transistor having its gate connected to the inverter output, a second field effect transistor having its gate connected to the output terminal, the field effect transistors being alternatingly rendered conductive and connected to provide complementary switching operations in the input means.

Claim 12

Control apparatus for providing a train of pulses, the width of the pulses to vary in dependence upon a control signal, the dependence to represent a particular function within a particular range for the control signal, the apparatus having a pulse generator for providing a pulse train and having a variable signal input terminal, the improvement comprising: the pulse generator having an output terminal; input means for the pulse generator and connected between a source for the control signal and said input terminal and including plural components including interconnected resistances; and a switching circuit connected to be responsive to the output of the pulse generator and providing switching operation in the input means for variation of the transfer function of the input means; the switching circuit including an inverter connected to the output terminal, a first field effect transistor having its gate connected to the inverter output, a second field effect transistor having its gate connected to the output terminal, the field effect transistors being alternatingly rendered conductive and connected to provide complementary switching operations in the input means.

Claim 13

Control apparatus as in claim 9, the input network including two resistances, the transistors providing effective resistance control respectively through short circuiting of the resistances.

Claim 14

Apparatus connected to a controller that processes an error signal in accordance with a transfer function determined by at least one parameter, the controller including resistances that determine the parameter, there being a switch connected to the resistances to provide intermittent switching action for effective resistance and parameter control, the switch provided to respond to a train of pulses, the apparatus comprising: a voltage controlled pulse generator having output connected to the switch for providing thereto pulses having width depending upon voltage control; a resistive input network connected to receive a control voltage, further connected to receive the width modulated switching pulses in feedback configuration, for controlling effective resistance of the network in dependence upon the width of these pulses; and circuit means connecting the network to the generator to provide the voltage control thereto as modified by the controlled reSistance of the network for obtaining pulse width modulation to be effective as variable duration switching signals for the switch as controlling effective resistance of the resistances as connected to the controller.

Claim 15

Apparatus connected to a controller that processes an error signal in accordance with a transfer function determined by at least one parameter, the controller including resistances that determine the parameter, there being a switch connected to the resistances to provide intermittent switching action for effective resistance and parameter control, the switch provided to respond to a train of pulses, the apparatus comprising: a voltage controlled pulse generator having output connected to the switch for providing thereto pulses having width depending upon voltage control; a resistive input network connected to receive a control voltage, further connected to receive the width modulated switching pulses in feedback configuration, for controlling effective resistance of the network in dependence upon the width of these pulses; and circuit means connecting the network to the generator to provide the voltage control thereto as modified by the controlled reSistance of the network for obtaining pulse width modulation to be effective as variable duration switching signals for the switch as controlling effective resistance of the resistances as connected to the controller.

Claim 16

Apparatus as in claim 11, the input network including a biasing source, the circuit means including an integrator, the connection between generator output and network providing reset action feedback control for function generation.

Claim 17

Apparatus as in claim 11, the connection including double connection means for controlling the network separately in dependence upon the pulses and the inverted pulses.