MK3721 Low Cost 3.3 Volt VCXO I C R O C LOC K Description Features The MK3721 is ICS/MicroClock’s lowest cost, low jitter, high performance 3.3 volt VCXO designed to replace expensive VCXO modules. The on-chip Voltage Controlled Crystal Oscillator accepts a 0 to 3.3 V input voltage to cause the output clocks to vary by ±100 ppm. Using ICS/MicroClock’s patented VCXO techniques, the device uses an inexpensive external pullable crystal in the range of 16.2 - 28 MHz to produce a VCXO output clock at that same frequency. • Packaged in 8 pin SOIC • 3.3 V operating voltage • 16.2 MHz to 28 MHz operation • Uses an inexpensive external crystal • On-chip VCXO (patented) with pull range of 200 ppm (minimum) • VCXO tuning voltage of 0 to 3.3 V • 12 mA output drive capability at TTL levels • Advanced, low power, sub-micron CMOS process • For frequencies between 8 MHz to 16 MHz, use the MK3711A. For frequencies between 1 MHz and 8 MHz, use the MK3713. For higher than 28 MHz, use the MK3732-05 ICS/MicroClock manufactures the largest variety of Set-Top Box and multimedia clock synthesizers for all applications. If more clock outputs are needed, see the MK3732 or MK377x family of parts. Consult ICS/MicroClock to eliminate VCXOs, crystals and oscillators from your board. Block Diagram VIN X1 16.2 -28 MHz pullable crystal X2 MDS 3721 B Output Buffer Voltage Controlled Crystal Oscillator 1 16.2 - 28 MHz Clock (REFOUT) Revision 082800 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose •CA • 95126• (408)295-9800tel • www.icst.com MK3721 Low Cost 3.3 Volt VCXO I C R O C LOC K Pin Assignment MK3721 X1 1 8 X2 VDD 2 7 DC VIN 3 6 REFOUT (VCXO) GND 4 5 DC 8 pin (150 mil) SOIC Pin Descriptions Number Name Description 1 X1 Crystal connection. Connect to a pullable 16.2 - 28 MHz crystal. 2 VDD VDD. Connect to + 3.3 V. 3 VIN Voltage input to VCXO. Zero to 3.3 V analog input which controls the frequency of the VCXO. 4 GND Connect to ground. 5 DC Don't Connect anything to this pin. 6 REFOUT VCXO CMOS level clock output matches the nominal frequency of the crystal. 7 DC Don't Connect anything to this pin. 8 X2 Crystal connection. Connect to a pullable 16.2 - 28 MHz crystal. Crystal Specifications Correlation (load) capacitance Initial accuracy Drift over temperature and aging C0/C1 ratio ESR MDS 3721 B 14 pF ±20 ppm maximum ±50 ppm maximum 240 maximum 35 Ω maximum 2 Revision 082800 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose •CA • 95126• (408)295-9800tel • www.icst.com MK3721 Low Cost 3.3 Volt VCXO I C R O C LOC K Electrical Specifications Parameter Conditions Minimum Typical Maximum Units 7 VDD+0.5 70 260 150 V V °C °C °C 3.45 V V V V mA mA 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 = 3.3 V unless noted) Operating Voltage, VDD Output High Voltage, VOH Output Low Voltage, VOL Output High Voltage, VOH, CMOS level Operating Supply Current, IDD Short Circuit Current VIN, VCXO control voltage IOH=-12mA IOL=12mA IOH=-4mA No Load 3.15 2.4 0.4 VDD-0.4 4 ±50 0 3.3 16.2 28 ±30 1.5 1.5 60 AC CHARACTERISTICS (VDD = 3.3 V unless noted) Input Crystal Frequency Input Crystal Accuracy Output Clock Rise Time Output Clock Fall Time Output Clock Duty Cycle Maximum Absolute Jitter, short term Output frequency pullability, note 2 Notes: 0.8 to 2.0V 2.0 to 0.8V At VDD/2 40 0V ≤ VIN ≤ 3.3 V ±100 50 ±55 MHz ppm ns ns % ps ppm 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 a ICS/MicroClock approved pullable crystal. External Components The MK3721 requires a minimum number of external components for proper operation. A decoupling capacitor of 0.01µF should be connected between VDD and GND on pins 2 and 4, as close to the MK3721 as possible. A series termination resistor of 33 Ω may be used for the clock output. The input crystal must be connected as close to the chip as possible. The input crystal should be a parallel mode, pullable, AT cut, with 14 pF load capacitance. See previous page for crystal specifications. Consult ICS for recommended suppliers. IMPORTANT - read application note MAN05 before laying out the PCB. MDS 3721 B 3 Revision 082800 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose •CA • 95126• (408)295-9800tel • www.icst.com MK3721 Low Cost 3.3 Volt VCXO I C R O C LOC K Package Outline and Package Dimensions (For current dimensional specifications, see JEDEC Publication No. 95.) 8 pin SOIC E H INDEX AREA D A A1 C e B Symbol A A1 B C D E e H h L Inches Min Max 0.0532 0.0688 0.0040 0.0098 0.0130 0.0200 0.0075 0.0098 0.1890 0.1968 0.1497 0.1574 .050 BSC 0.2284 0.2440 0.0099 0.0195 0.0160 0.0500 Millimeters Min Max 1.35 1.75 0.10 0.24 0.33 0.51 0.19 0.24 4.80 5.00 3.80 4.00 1.27 BSC 5.80 6.20 0.25 0.50 0.41 1.27 L Ordering Information Part/Order Number MK3721S MK3721STR Marking MK3721S MK3721S Shipping packaging tubes tape and reel Package 8 pin SOIC 8 pin SOIC Temperature 0-70 °C 0-70 °C While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems Incorporated (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. MDS 3721 B 4 Revision 082800 Integrated Circuit Systems, Inc. • 525 Race Street • San Jose •CA • 95126• (408)295-9800tel • www.icst.com