
Integrated Circuit Systems
Description
The MK2771-12 is a low cost, low jitter, high performance VCXO and clock synthesizer designed for set-top boxes. The on-chip Voltage Controlled Crystal Oscillator accepts a 0 to 3V input voltage to cause the output clocks to vary by ±100 ppm. Using MicroClock’s patented VCXO and analog Phase-Locked Loop (PLL) techniques, the device uses an inexpensive 13.5 MHz crystal input to produce multiple output clocks including a selectable processor clock, selectable UART and audio clocks, a fixed 11.0592 MHz, and two low skew copies of the 27 MHz. All clocks are frequency locked to the 27.00 MHz output (and to each other) with zero ppm error, so any output
can be used as the VCXO output.
FEATUREs
• Packaged in 20 pin SOIC
• Pin for pin and functional upgrade to MK2771-02
• Uses an inexpensive 13.5 MHz crystal
• On-chip patented VCXO with pull range of 200 ppm
• VCXO tuning voltage of 0 to 3 V
• Processor frequency of 16.67 MHz, 20 MHz, 32 MHz, 40 MHz, or 50 MHz
• Zero ppm synthesis error in all clocks (all exactly track 27MHz VCXO) - patented
• 25 mA output drive capability at TTL levels
• Advanced, low power, sub-micron CMOS process
• 5 V operating voltage