Abstract: A telecommunication filter arrangement comprising two similar filter cells (T1, S1a, S1b, R1a, R1b; T2, S2a, S2b, R2a, R2b) coupled in cascade to provide a POTS/ADSL splitter. The filter arrangement further comprises at third filter cell (C3, R3, S3) coupled in-between the two other filter cells and comprising a cell capacitor (C3) series coupled with the parallel connection of a cell coil (S3) and a cell resistor (R3). A 3rd order filter is so provided and the filter arrangement behaves as known 5th order filter but with a fixed “switchable insertion loss circuit”. This filter arrangement is thereby cheap, simple and has a small size with respect to the known filter arrangements, while providing good performances.

Abstract: An operational amplifier arrangement having a non-linear amplifier and a linear amplifier, both having a pair of input terminals one of which is coupled to an arrangement input terminal, and both having an output terminal that is coupled to an arrangement output terminal. The output terminal of the non-linear amplifier is further coupled to the output terminal of the linear amplifier via a series impedance. The output terminal of the linear amplifier is coupled to the arrangement output terminal via a terminating impedance. The arrangement includes an active back termination arrangement coupled between the arrangement output terminal and either one of the pair of input terminals of the linear amplifier. Preferably, the linear amplifier is receiving a supply voltage that exceeds the supply voltage received by the non-linear amplifier.

Abstract: A line driver having a non-linear amplifier that is arranged to provide a first output signal, which is an amplified input signal. The line driver also includes an analog linear amplifier providing a second output signal based on the difference between the input signal and the first output signal, placed in parallel with the non-linear amplifier. The line driver also includes a device to combine the first output signal and the second output signal to provide a total output signal to an output line.

Abstract: An operational amplifier arrangement is disclosed which comprises a non-linear amplifier and a linear amplifier, both having a pair of input terminals one of which is coupled to an arrangement input terminal, and both having an output terminal which is coupled to an arrangement output terminal, whereby the output terminal of said non-linear amplifier is further coupled to the output terminal of said linear amplifier via a series impedance, whereby the output terminal of said linear amplifier is coupled to the arrangement output terminal via a terminating impedance, and whereby the arrangement further includes an active back termination arrangement coupled between the arrangement output terminal and either one of said pair of input terminals of said linear amplifier. In a preferred embodiment said linear amplifier is operating between a power supply which exceeds the supply voltage of the power supply of said non-linear amplifier. Differential embodiments of this basic configuration are also described.

Abstract: Modem systems comprising Asymmetric Digital Subscriber Line modems (1,21) or ADSL modems (1,21) coupled via bidirectional lines (40) are insufficiently flexible. By providing the modems (1,21) with tunable analog filters (4,23), the upstream/downstream bandwidths can be adapted, in response to request signals. In case of said tunable analog filter being a tunable high pass filter (4) located in a first network modem (1), more bandwidth for the downstream can be introduced. In case of said request signal originating from a generator (31) in a second terminal modem (21), the terminal can request more bandwidth for the downstream, for example for video on demand. In case of said tunable analog filter being a tunable low pass filter (23) in said first modem (21), less bandwidth for the upstream can be introduced, thereby creating more bandwidth for the downstream. Said tunable analog filter (4,23) comprises a filter element like a capacity which is (de)activatable via a switch like a relais or a transistor.

Abstract: The present invention is related to a Line driver for amplifying an input signal, said line driver comprising: a first input terminal (11) for receiving said input signal, a non-linear amplifier (3) connected to said input terminal (11) and arranged to provide a first output signal at a first output terminal (13), a digital to analogue converter (15) arranged to transform said input signal to an analogue input signal, an analogue linear amplifier (5) comprising a second (6) and a third input terminal (8) and a second output terminal (10), set up as a comparator between a first correction signal provided at said second input terminal (6) and a second correction signal provided at said third input terminal (8) and arranged to provide a second output signal at said second output terminal (10), combining means arranged to combine said first output signal and said second output signal to provide a total output signal to an output line (7), a first operational amplifier (12) configured to sense the current of said

Abstract: The present invention is related to a Line driver for amplifying an input signal, said line driver comprising: a first input terminal (11) for receiving said input signal, a non-linear amplifier (3) connected to said input terminal (11) and arranged to provide a first output signal at a first output terminal (13), a digital to analogue converter (15) arranged to transform said input signal to an analogue input signal, an analogue linear amplifier (5) comprising a second (6) and a third input terminal (8) and a second output terminal (10), set up as a comparator between a first correction signal provided at said second input terminal (6) and a second correction signal provided at said third input terminal (8) and arranged to provide a second output signal at said second output terminal (10), combining means arranged to combine said first output signal and said second output signal to provide a total output signal to an output line (7), a first operational amplifier (12) configured to sense the current of said