Features: ·Easy to use
·Clock to center frequencyratio accuracyg0.6%
·Filter cutoff frequency stabilitydirectlydependent on external clock quality
·Low sensitivityto external component variation
·Separate highpass (or notch or allpass), bandpass, lowpass outputs
·fO c Q range up to 200 kHz
·Operation up to 30 kHz
·20-pin 0.3× wide Dual-In-Line package
·20-pin Surface Mount (SO) wide-body packageApplicationThe MF10 is a general-purpose dual second-order state variable filter whose center frequency is proportional to the frequency of the square wave applied to the clock input (fCLK). By connecting pin 12 to the appropriate DC voltage, the filter center frequency fO can be made equal to either fCLK/100 or fCLK/50. fO can be very accurately set (within g6%) by using a crystal clock oscillator, or can be easily varied over a wide frequency range by adjusting the clock frequency. If desired, the fCLK/fO ratio can be altered by external resistors as inFigures 9, 10, 11, 13, 14 and15 . The filter Q and gain are determined by external resistors. All of the five second-order filter types can be built using either section of the MF10. These are illustrated inFigures 1 hrough5 along with their transfer functions and some related equations.Figure 6 shows the effect of Q on the shapes of these curves. When filter orders greater than two are desired, two or more MF10 sections can be cascaded.
Pinout
SpecificationsIf Military/Aerospace specified devices are required, please contact the National Semiconductor Sales office/Distributors for availability and specifications.
Supply Voltage (Va b Vb)...........14V
Voltage at Any Pin ............V++0.3V
......V--0.3V
Input Current at Any Pin (Note 2)......5 mA
Package Input Current (Note 2)......20 mA
Power Dissipation (Note 3) .......500 mW
Storage Temperature...........150°C
ESD Susceptability (Note 11) .......2000V
Soldering Information
N Package: 10 sec. ............260°C
J Package: 10 sec. ............300°C
SO Package: Vapor Phase (60 Sec.) ...215°C
Infrared (15 Sec.).............220°C
See AN-450 "Surface Mounting Methods and Their Effect on Product Reliability"(Appendix D) for other methods of
soldering surface mount devices.
| Temperature Min |
0 deg C |
| Temperature Max |
70 deg C |
| FilterType |
Universal |
| Filter Order Max |
4 |
| Max PLL Freq |
0.03 MHz |
| View Using Catalog |
DescriptionThe MF10 consists of 2 independent and extremely easy to use, general purpose CMOS active filter building blocks. Each block, together with an external clock and 3 to 4 resistors, can produce various 2nd order functions. Each building block has 3 output pins. One of the outputs can be configured to perform either an allpass, highpass or a notch function; the remaining 2 output pins perform lowpass and bandpass functions. The center frequency of the lowpass and bandpass 2nd order functions can be either directly dependent on the clock frequency, or they can depend on both clock frequency and external resistor ratios. The center frequency of the notch and allpass functions is directly dependent on the clock frequency, while the highpass center frequency depends on both resistor ratio and clock. Up to 4th order functions can be performed by cascading the two 2nd order building blocks of the MF10; higher than 4th order functions can be obtained by cascading MF10 packages. Any of the classical filter configurations (such as Butterworth, Bessel, Cauer and Chebyshev) can be formed. For pin-compatible device with improved performance refer to LMF100 datasheet.
MF10 Data Sheet
