US 4,866,587 A · Electronic ringing signal generator

Abstract

A switching power amplifier circuit has the functions of a power inverter and a switching amplifier embodied into one integral circuit. Two high frequency switching inverter circuits are connected back to back sharing the same inverter power transformer. One switching inverter circuit processes power from an input rail to an output capacitor while the other switching inverter circuit processes power from the output capacitor to the input rail. The output capacitor voltage is regulated with respect to a signal input in order to obtain the desired output signal waveform. A blocking capacitor in the output absorbs the DC component of the output capacitor voltage and allows a pure AC ringing signal to be applied to the load. In an application as a ringing generator circuit the signal input is supplied by a ringing signal oscillator circuit.

Claims21

Dependent claims

An electronic ringing signal generator comprising:

an input for accepting a DC voltage source;
an output for coupling to a ringing signal load;
a first switching circuit concerned to the input;
a second switching circuit connected to the output;
the first and second switching circuits coupled to a bidirectional power coupling circuit;
a reference signal input for accepting an AC reference signal;
a first control circuit for regulating power flow from the input to the output by controlling the first switching circuit to connect the input to the bidirectional power coupling circuit when an AC voltage at the output is less than the AC reference signal;
and
a second control circuit for regulating power flow from the output to the input by controlling the second switching circuit to connect the output to the bidirectional power coupling circuit when an AC voltage at the output is greater than the AC reference signal.

6 more elements

An electronic ringing signal generator comprising:

a power switching amplifier, including;
an input and an output, the output including means for accepting a ringing signal load, a capacitor in parallel with the means for accepting and a DC block capacitor in series with the means for accepting,
a transformer having a first winding and a second winding,
a first power switch coupling the input to the first winding,
a first diode connected at least in parallel with the first power switch,
a first current sensing resistor in series with the first power switch,
a second power switch coupling the output to the second winding,
a second diode connected at least in parallel with the second power switch,
a second current sensing resistor in series with the second power switch;
and
a feedback circuit including;
a voltage sensing circuit connected in parallel with a series connection of the DC blocking capacitor and the means for accepting a ringing signal load,
an AC reference source having an AC reference signal input and a DC reference signal input,
a first peak current control circuit, including;
a first error amplifier having non-inverting and inverting input terminals, the non-inverting input terminal being coupled to an output of the AC reference source and the inverting input terminal being coupled to the voltage sensing circuit, a current sensing input coupled to the first current sensing resistor and a drive output coupled to a drive terminal of the first power switch;
and
a second peak current control circuit, including;
a second error amplifier having non-inverting and inverting input terminals, the inverting input terminal being coupled to an output of the AC reference source and the noninverting input terminal being coupled to the voltage sensing circuit, a current sensing input coupled to the second current sensing resistor and a drive output coupled to a drive terminal of the second power switch.

15 more elements

A ringing signal generator, comprising:

an input for accepting a power signal;
an output for supplying a ringing signal;
a voltage sensing circuit for sensing a voltage at the output, and an AC reference signal input;
a first switching circuit operative for processing power from the input to the output, and including;
a first regulation circuit for regulating power flow from the input to the output and having an error amplifier positively responsive to the AC reference signal input and negatively responsive to the voltage sensing circuit;
and
a second switching circuit operative for processing power from the output to the input and including;
a second regulation circuit for regulating power flow from the output to the input and having an error amplifier negatively responsive to the AC reference signal input and positively responsive to the voltage sensing circuit.

5 more elements

A power switching amplifier comprising:

an input for accepting a DC voltage source;
an output for coupling to a power signal load;
a first switching circuit connected to the input;
a second switching circuit connected to the output;
the first and second switching circuits coupled to a bidirectional power coupling circuit;
a signal input for accepting a signal to be amplified;
a first control circuit for regulating power flow from the input to the output by controlling the first switching circuit to connect the input to the bidirectional power coupling circuit when a voltage at the output is less than an amplitude of the signal to be amplified;
and
a second control circuit for regulating power flow from the output to the input by controlling the second switching circuit to connect the output to the bidirectional power coupling circuit when a voltage at the output is greater than an amplitude of the signal to be amplified.

6 more elements

A power switching amplifier, comprising:

an input and an output, the output including means for accepting a load, a storage capacitor in parallel with the means for accepting and a DC blocking capacitor in series with the means for accepting,
a transformer having a first winding and a second winding,
a first power switch coupling the input to the first winding,
a first diode connected at least in parallel with the first power switch,
a first current sensing resistor in series with the first power switch,
a second power switch coupling the output to the second winding,
a second diode connected at least in parallel with the second power switch,
a second current sensing resistor in series with the second power switch;
and
a feedback circuit including:
a voltage sensing circuit connected in parallel with a series connection of the DC blocking capacitor and the means for accepting a load,
a signal input for accepting a signal to be amplified,
a first peak current control circuit, including;
a first error amplifier having non-inverting and inverting input terminals, the non-inverting input terminal being coupled to the signal input and the inverting input terminal being coupled to the voltage sensing circuit, a current sensing input coupled to the first current sensing resistor and a drive output coupled to a drive terminal of the first power switch;
and
a second peak current control circuit, including;
a second error amplifier having non-inverting and inverting input terminals, the inverting input terminal being coupled to the signal input and the non-inverting input terminal being coupled to the voltage sensing circuit, a current sensing input coupled to the second current sensing resistor and a drive output coupled to a drive terminal of the second power switch.

14 more elements

Dependencies are inferred from the claim text.

Electronic ringing signal generator

Life of this patent

Electronic ringing signal generator

Life of this patent

Abstract

Claims21