Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
301 words
A circuit for removing unwanted temporal portions of a voltage varying signal on the occurrence of a reset signal and for differentiating a resultant corrected signal with respect to a reference voltage, said circuit being characterised by: switch means (SW) responsive to said reset signal applied to a first input, said switch means, in operation, being responsive to said reset signal to divert a second input of the switch means (SW) to a second output from a first output and thence to return said second input to said first output; input capacitor means (C1) for receiving said input signal; first operational amplifier means (U1-B) having positive and negative inputs and an output connected to said second input of said switch means (SW), the positive input being connected to receive a voltage representative of the current through said input capacitor means (C1); storage capacitor means (C5) having one side connected to a reference voltage and having its other side in electrical connection to the negative input of the first operational amplifier means (U1-B) and said first output of the switch means (SW); inverting amplifier means (U2) connected to receive said second output of the switch means (SW); and second operational amplifier means (U1-A) for receiving said corrected signal from the inverting amplifier means (U2) and having a negative input which is connected through a first resistor (R3) and through the inverting amplifier means (U2) to said second output of the switch means, said negative input also being in electrical connection through said first resistor (R3) with said input capacitor means (C1) and with said positive input of said first operational amplifier means (U1-B), a positive input connected to a reference voltage, and providing a differentiated corrected signal at its output which is connected via a feedback resistor (R4) to said negative input.
Claim 2
Dependent Claim
301 words
A circuit for removing unwanted temporal portions of a voltage varying signal on the occurrence of a reset signal and for differentiating a resultant corrected signal with respect to a reference voltage, said circuit being characterised by: switch means (SW) responsive to said reset signal applied to a first input, said switch means, in operation, being responsive to said reset signal to divert a second input of the switch means (SW) to a second output from a first output and thence to return said second input to said first output; input capacitor means (C1) for receiving said input signal; first operational amplifier means (U1-B) having positive and negative inputs and an output connected to said second input of said switch means (SW), the positive input being connected to receive a voltage representative of the current through said input capacitor means (C1); storage capacitor means (C5) having one side connected to a reference voltage and having its other side in electrical connection to the negative input of the first operational amplifier means (U1-B) and said first output of the switch means (SW); inverting amplifier means (U2) connected to receive said second output of the switch means (SW); and second operational amplifier means (U1-A) for receiving said corrected signal from the inverting amplifier means (U2) and having a negative input which is connected through a first resistor (R3) and through the inverting amplifier means (U2) to said second output of the switch means, said negative input also being in electrical connection through said first resistor (R3) with said input capacitor means (C1) and with said positive input of said first operational amplifier means (U1-B), a positive input connected to a reference voltage, and providing a differentiated corrected signal at its output which is connected via a feedback resistor (R4) to said negative input.
Claim 3
Dependent Claim
97 words
A circuit as claimed in claim 1 characterised in that the negative input of said second operational amplifier means (U1-A) is also connected to a reference voltage through the first resistor (R3) and a filter capacitor (C2) which is connected between a second resistor (R2) and said first resistor, the negative input of said second operational amplifier means being in electrical connection through both said first and second resistors (R2,R3) to said input capacitor means (C1), to the output of said inverting amplifier means (U2) and to said positive input of said first operational amplifier means (U1-B).
Claim 4
Dependent Claim
43 words
A circuit as claimed in claim 1 or 2 characterised in that the negative input of said second operational amplifier means (U1-A) is in electrical connection with its output via said feedback resistor (R4) and a compensating capacitor (C3) connected in parallel therewith.
Claim 5
Dependent Claim
58 words
A circuit as claimed in claim 2 or 3 characterised in that a third resistor (R1) is connected between said second resistor (R2) and said input capacitor means (C1), said input capacitor means being connected through said third resistor (R1) with said inverting amplifier means (U2) and with said positive input of the first operational amplifier means (U1-B).
Claim 6
Dependent Claim
21 words
A circuit as claimed in any preceding claim characterised in that said reset signal is generated from a tri-phase servo signal.
Claim 7
Dependent Claim
30 words
A circuit as claimed in claim 5 characterised in that said reset signal is generated from the same tri- phase servo signal which is used to generate said input signal.
Claim 8
Dependent Claim
36 words
A circuit as claimed in any preceding claim characterised in that a storage resistor (R5) is connected in series between said storage capacitor means (C5) and said negative input of said first operational amplifier means (U1-B).
Claim 9
Dependent Claim
51 words
A circuit as claimed in claim 7 characterised in that one side of the storage resistor (R5) is connected to said first output of the switch means (SW) and said negative input of the first operational amplifier means (U1-B) and the other side is connected to said storage capacitor means (C5).