MK1422

For applications in portable computers, see the MK14223, which is specified to operate at 3.3V. It is possible to drive the MK1422 with a 3.3V, 14.318MHz clock by a.c. coupling using a 0.01F capacitor connected in series to the X1 pin. But the operating VDD on pin 2 must be 5V±10%. This technique is also effective if the input clock doesn't meet the VIH and VIL specifications on page 3.

The MK1422 is the ideal way to generate clocks for sound in portable computers. It provides clocks for Analog Devices' or Crystal Semiconductor's stereo codecs, and Yamaha's OPL3L, OPL3LS, and OPL4. The MK1422 uses either a 14.318 MHz crystal, or a 14.318 MHz bus clock input to synthesize the clocks required to drive the codec, and the 33.868 MHz required for the FM or wavetable music synthesizer. It includes a power down pin to save power without using a FET. In an 8 pin SOIC, the MK1422 can save component count, board space, and cost over surface mount crystals, and increase reliability by eliminating three mechanical devices from the board.

MicroClock offers many other parts with stereo codec support. MicroClock invented sound clocks,and has the widest product offering and greatest production experience on these devices. The MK1422 is pin compatible with MicroClock's popular MK1420 when the 14.318MHz clock output is not used. See the MK14223 for 3.3V.