SAN JOSE, California, March 30, 1999---Engineers at Mixed Signal Integration have developed a new series of switched capacitor filter ICs that operate at center/corner frequencies of 3 MHz and beyond with a choice of six different filter responses. The Selectable High Frequency Filter ICs have six pole Butterworth, Elliptic or Bessel responses or six pole full octave, one third octave or one sixth octave bandpass responses.

The high frequency operation of the MSHFS1-6 series opens up a new range of applications previously unavailable to lower performance parts. In communications systems for example, these filters extend beyond typical baseband applications to roles in the IF section. The frequency range of the MSHFS1-6 is popular in wireless alarm systems and wireless telephones. This same range allows them to function as luminance filters for video demodulation. Also, these high order filter ICs have much steeper roll-off and greater stop-band rejection than passive component approaches or low order op-amp based solutions.

The MSHFS1, MSHFS2 and MSHFS5 operate at corner frequencies up to 3 MHz while drawing typical supply currents of 24 mA. The MSHFS3, MSHFS4 and MSHFS6 work up to 1 MHz with only 4 mA typical supply current. The MSHFS1, MSHFS3, MSHFS5 and MSHFS6 combine all six filter responses into an 8 pin DIP. They have a single input, unity gain and a fixed clock to corner ratio. The MSHFS1 and MSHFS3 have a 6.25:1 clock to corner ratio. The MSHFS5 and MSHFS6 have a 12.5:1 clock to corner ratio. The MSHFS2 and MSHFS4 are 16 pin versions that include all 6 responses, a four input multiplexor, externally selectable gain setting pin, power down function and a clock to corner ratio select. The gain can be 0, 10 or 20 dB. The clock to corner ratio can be either 12.5:1 or 6.25:1.

The devices use a switched capacitor filter design that reduces the need for external components. Only decoupling capacitors and an external CMOS level clock are required. The MSHFS1-6 take a single +5V supply.

The MSHFS1P is available in an 8 pin plastic DIP package for $5.45 in 1000 piece quantities. The MSHFS2P is available in a 16 pin plastic DIP package for $5.80 in 1000 piece quantities. The MSHFS3P, MSHFS5P and MSHFS6P come in an 8 pin plastic DIP. The MSHFS4P is in a 16 pin plastic DIP. The MSHFS1-6 are also available in SO packages.

MIXED SIGNAL INTEGRATION is an integrated circuit company specializing in analog and mixed signal standard products and custom ASICs in CMOS technologies. For more information, contact MSI at 2157F O'Toole Ave., San Jose, California 95131. Telephone: 408-434-6305. Fax: 408-434-6417. E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.. Web Site: