Filter device comprising switched-capacitance integrating networks

A filter device including a first group of switched-capacitance integrating networks for simulating an analog high-pass ladder filter comprising a first and a second input terminal, a first and a second output terminal, a plurality of series-connected capacitors . . . , C.sub.2k-1, C.sub.2k+1, C.sub.2k+3, . . . interconnecting the first input terminal to the first output terminal, a plurality of admittances . . . Y.sub.2k, Y.sub.2k+2, . . . each having one end electrically connected to electrically-connected electrodes of a respective pair of said capacitors and having the other end electrically-connected to the second input and output terminals, said admittances comprising series-connected capacitors, inductors C.sub.2k, L.sub.2k ;

• C.sub.2k+2, L.sub.2k+2 ;
• respectively
• said first group comprising a plurality of pairs of switched-capacitance integrating networks RB.sub.2k-2, RA.sub.2k-2 ;
• RA.sub.2k, RB.sub.2k ;
• RB.sub.2k+2, RA.sub.2k+2 ;
• each network having three inputs and one output;
• the first input of the network RA.sub.2k being connected to the output of the network RB.sub.2k-2, the second input to the output of the network RB.sub.2k+2, and the third input to the output of the network RB.sub.2k ;
• the first input of the network RB.sub.2k being connected to the output of the network RB.sub.2k-2, the second input to the output of the network RA.sub.2k and the third input to the output of the network RB.sub.2k+2 ;
• the network RA.sub.2k having the following transfer functions:
• ##EQU51## between the first input and the output;
• ##EQU52## between the second input and the output;
• and ##EQU53## between the third input and the output;
• the network RB.sub.2k having the following transfer functions:
• ##EQU54## between the first input and the output;
• ##EQU55## between the second input and the output;
• and ##EQU56## between the third input and the output;
• where:
• ##EQU57## s is the LAPLACE operator, and R is an arbitrary constant having the units of resistance.