MK2771-15 VCXO and Set-Top Clock Source Description Features The MK2771-15 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 ICS/MicroClock’s patented VCXO and analog Phase-Locked Loop (PLL) techniques, the device uses an inexpensive 13.5 MHz pullable crystal input to produce multiple output clocks including two selectable processor clocks, a selectable audio clock, two communications clocks, and three fixed clocks. All clocks are frequency locked to the 27.00MHz output (and to each other) with zero ppm error, so any output can be used as the VCXO output. • Packaged in 28 pin SSOP (QSOP) • Ideal for systems using Oak’s MPEG decoders • On-chip patented VCXO with pull range of 200ppm • VCXO tuning voltage of 0 to 3 V • Processor frequencies include 33.3, 40, 50, 66.6, 81, and 100 MHz • Audio clocks of 8.192 MHz, 11.2896 MHz, 12.288 MHz and 18.432 MHz • Zero ppm synthesis error in all clocks (all exactly track 27 MHz VCXO) • Uses an inexpensive 13.5 MHz pullable crystal • Full CMOS output swings with 25 mA output drive capability at TTL levels • Advanced, low power, sub-micron CMOS process • 5 V operating voltage with 3.3 V capable I/O Block Diagram VDD PCS2:0 ACS1:0 GND VDDIO 3 Output Buffers 2 Output Buffer Clock Synthesis Circuitry SC Output Buffers VIN 13.5 MHz pullable crystal X1 X2 Voltage Controlled Crystal Oscillator 2 Processor Clocks Audio Clock 2 Comm. Clocks Output Buffer 54.00 MHz ÷2 Output Buffer 27.000 MHz ÷2 Output Buffer 13.500 MHz 1 Revision 122899 Printed 11/16/00 Integrated Circuit Systems, Inc.• 525 Race Street • San Jose • CA • 95126 •(408) 295-9800tel• www.icst.com MDS 2771-15 E MK2771-15 VCXO and Set-Top Clock Source Processor Clock Select Table (MHz) Pin Assignment PCS0 X2 X1 VDD VDD VIN VDDIO VDD SC GND PCLK1 PCLK2 PCS1 ACLK 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28 27 26 25 24 23 22 21 20 19 18 17 16 15 ACS1 ACS0 54M 27M GND CCLK1 VDD VDD PCS2 GND GND CCLK2 13.5M DC Name PCS0 X2 X1 VDD VIN VDDIO SC GND PCLK1 PCLK2 PCS1 ACLK DC 13.5M CCLK2 PCS2 VDD CCLK1 27M 54M ACS0 ACS1 PCS1 0 0 1 1 0 0 1 1 PCS0 0 1 0 1 0 1 0 1 Audio Clock Table ACS1 ACS0 ACLK (MHz) 0 0 8.192 0 1 11.2896 1 0 12.288 1 1 18.432 PCLK1 27.500 33.333 33.326 50.000 32.400 40.000 TEST TEST PCLK2 Off 66.666 83.314 100.000 81.000 33.333 TEST TEST Comm Clock Table (MHz) SC 0 M 1 CCLK1 18.432 11.0592 11.0592 CCLK2 24.576 18.432 24.576 0 = connect directly to ground, 1 = connect directly to VDDIO, M = leave floating or unconnected Pin Descriptions Number 1 2 3 4, 5, 8 6 7 9 10, 18, 19, 24 11 12 13 14 15 16 17 20 21, 22 23 25 26 27 28 PCS2 0 0 0 0 1 1 1 1 Type I XO XI P I P TI P O O I O O O I P O O O I I Description Processor Clock Select 0. Selects PCLKs on pins 11 and 12. See table above. Int. pull-up. Crystal connection. Connect to a pullable 13.5 MHz crystal. Crystal connection. Connect to a pullable 13.5 MHz crystal. Connect to +5V. Voltage Input to VCXO. Zero to 3V signal which controls the frequency of the VCXO. Connect to +3.3V or +5V. Amplitude of inputs must, and outputs will, match this. Communications clock select pin. Biased to M level if floating. Connect to ground. Processor Clock output number 1. Determined by status of PCS2:0 Processor Clock output number 2. Determined by status of PCS2:0 Processor Clock Select 1. Selects PCLKs on pins 11 and 12. See table above. Int. pull-up. Audio Clock Output. Determined by status of ACS1, ACS0 per table above. Don't Connect anything to this pin. 13.50 MHz VCXO clock output. Communications Clock Output 2 determined by status of SC per table above. Processor Clock Select 2. Selects PCLKs on pins 11 and 12. See table above. Int. pull-up. Connect to +5V. Communications Clock Output 1 determined by status of SC per table above. 27.00 MHz VCXO clock output. 54.00 MHz VCXO clock output. Audio Clock Select 0. Selects ACLK on pin 14. See table above. Internal pull-up. Audio Clock Select 1. Selects ACLK on pin 14. See table above. Internal pull-up. Key: I = Input; TI = Tri-level input; O = output; P = power supply connection; XI, XO = crystal connections 2 Revision 122899 Printed 11/16/00 Integrated Circuit Systems, Inc.• 525 Race Street • San Jose • CA • 95126 •(408) 295-9800tel• www.icst.com MDS 2771-15 E MK2771-15 VCXO and Set-Top Clock Source Electrical Specifications Parameter Conditions Minimum Typical Maximum Units 7 VDDIO+0.5 70 260 150 V V °C °C °C 5.25 5.25 V V V V V V V V V V V mA mA pF ppm V ABSOLUTE MAXIMUM RATINGS (note 1) Supply voltage, VDD Inputs and Clock Outputs Ambient Operating Temperature Soldering Temperature Storage temperature Referenced to GND Referenced to GND -0.5 0 Max of 10 seconds -65 DC CHARACTERISTICS (VDD, VDDIO = 5.0V unless noted) Operating Voltage, VDD Operating Voltage, VDDIO Input High Voltage, VIH, X1 pin only Input Low Voltage, VIL, X1 pin only Input High Voltage, VIH (except SC & PCS2) Input Low Voltage, VIL (except SC & PCS2) Input High Voltage, VIH, SC & PCS2 only Input Low Voltage, VIL, SC & PCS2 only Output High Voltage, VOH Output Low Voltage, VOL Output High Voltage, VOH, CMOS level Operating Supply Current, IDD+IDDIO (3.3V) Short Circuit Current Input Capacitance Frequency synthesis error VIN, VCXO control voltage 4.75 3.15 3.5 for all inputs/outputs 2.5 2.5 1.5 2 0.8 VDDIO-0.5 0.5 IOH=-25mA IOL=25mA IOH=-8mA No Load, note 2 Each output Except X1, X2 All clocks 2.4 0.4 VDDIO-0.4 46+27 ±100 7 0 0 3 AC CHARACTERISTICS (VDD, VDDIO = 5.0V unless noted) Input Frequency 13.500000 MHz Output Clock Rise Time 0.8 to 2.0V, no load 1.5 ns Output Clock Fall Time 2.0 to 0.8V, no load 1.5 ns Output Clock Duty Cycle At VDDIO/2 40 50 60 % Maximum Absolute Jitter, short term 300 ps VCXO Pullability Note 3 -100 100 ppm Notes: 1. Stresses beyond those listed under Absolute Maximum Ratings could cause permanent damage to the device. Prolonged exposure to levels above the operating limits but below the Absolute Maximums may affect device reliability. 2. With PCLK at 100 MHz. 3. With a pullable crystal that conforms to ICS’ specifications External Components The MK2771-15 requires a minimum number of external components for proper operation. Decoupling capacitors of 0.01µF should be connected between VDD (or VDDIO) and GND on pins 5 and 24, 7 and 10, 22 and 19, and 21 and 18, as close to the MK2771-15 as possible. VDD on pin 8 can be connected directly to the VDD on pin 21. A series termination resistor of 33 Ω may be used for each clock output.The 13.500 MHz crystal must be connected as close to the chip as possible. The crystal should be a parallel mode, pullable, with load capacitance of 14 pF. Consult ICS/MicroClock for recommended suppliers. See MAN05 for recommended layout of the chip and external components. 3 Revision 122899 Printed 11/16/00 Integrated Circuit Systems, Inc.• 525 Race Street • San Jose • CA • 95126 •(408) 295-9800tel• www.icst.com MDS 2771-15 E MK2771-15 VCXO and Set-Top Clock Source Pullable Crystal Specifications Frequency Correlation (load) Capacitance CO/C1 ESR Operating Temperature Initial Accuracey Temperature plus Aging Stability 13.500000 MHz 14 pF 240 max 35 Ω max 0 to 70 °C ±20 ppm ±50 ppm Package Outline and Package Dimensions (For current dimensional specifications, see JEDEC Publication No. 95.) 28 pin SSOP E1 E D A1 c e b A Symbol A A1 b c D e E E1 L Inches Min Max 0.053 0.069 0.004 0.010 0.008 0.012 0.007 0.010 0.386 0.394 .025 BSC 0.228 0.244 0.150 0.157 0.016 0.050 Millimeters Min Max 1.35 1.75 0.102 0.254 0.203 0.305 0.191 0.254 9.804 10.008 0.635 BSC 5.791 6.198 3.810 3.988 0.406 1.270 L Ordering Information Part/Order Number MK2771-15R MK2771-15RTR Marking MK2771-15R MK2771-15R Shipping packaging tubes tape and reel Package Temperature 28 pin SSOP (QSOP) 0-70 °C 28 pin SSOP (QSOP) 0-70 °C While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems (ICS) assumes no responsibility for either its use or for the infringement of any patents or other rights of third parties, which would result from its use. No other circuits, patents, or licenses are implied. This product is intended for use in normal commercial applications. Any other applications such as those requiring extended temperature range, high reliability, or other extraordinary environmental requirements are not recommended without additional processing by ICS. ICS reserves the right to change any circuitry or specifications without notice. ICS does not authorize or warrant any ICS product for use in life support devices or critical medical instruments. 4 Revision 122899 Printed 11/16/00 Integrated Circuit Systems, Inc.• 525 Race Street • San Jose • CA • 95126 •(408) 295-9800tel• www.icst.com MDS 2771-15 E