INTRODUCTION Oscillators are an important component of radio frequency (RF) and digital devices. Today, product design engineers often do not find themselves designing oscillators because the oscillator circuitry is provided on the device. However, the circuitry is not complete. Selection of the CRYSTAL and external capacitors have been left to the product design engineer. If the incorrect CRYSTAL and external capacitors are selected, it can lead to a product that does not operate properly, fails prematurely, or will not operate over the intended temperature range. For product success it is important that the designer understand how an oscillator operates in order to select the correct CRYSTAL.
General Description The ICS844256D is a CRYSTAL-to-LVDS Clock Synthesizer/Fanout Buffer designed for SONET and Gigabit Ethernet applications. The output frequency can be set using the frequency select pins and a 25MHz CRYSTAL for Ethernet frequencies, or a 19.44MHz CRYSTAL for SONET. The low phase noise characteristics of the ICS844256D make it an ideal clock for these demanding applications.
Features • Six differential LVDS output pairs • CRYSTAL oscillator interface • Output frequency range: 62.5MHz - 625MHz • CRYSTAL input frequency range:15.625MHz - 25.5MHz • RMS phase jitter @ 125MHz, using a 25MHz CRYSTAL (1.875MHz – 20MHz): 0.43ps (typical) • Full 3.3V or mixed 3.3V core, 2.5V output supply mode • 0°C to 70°C ambient operating temperature • Available in lead-free (RoHS 6) package
GENERAL DESCRIPTION The ICS844256 is a CRYSTAL-to-LVDS Clock Synthesizer/Fanout Buffer designed for SONET and Gigabit Ethernet applications and is a member of the HiperClockS™ family of High Performance Clock Solutions from IDT. The output frequency can be set using the frequency select pins and a 25MHz CRYSTAL for Ethernet frequencies, or a 19.44MHz CRYSTAL for SONET. The low phase noise characteristics of the ICS844256 make it an ideal clock for these demanding applications.
FEATURES • Six LVDS outputs • CRYSTAL oscillator interface • Output frequency range: 62.5MHz to 622.08MHz • CRYSTAL input frequency range: 15.625MHz to 25.5MHz • RMS phase jitter at 125MHz, using a 25MHz CRYSTAL (1.875MHz to 20MHz): 0.48ps (typical) • Full 3.3V or 3.3V core, 2.5V output supply mode • 0°C to 70°C ambient operating temperature • Available in both standard (RoHS 5) and lead-free (RoHS 6) packages
General Description The Supertex HV508 is a 45V liquid CRYSTAL shutter driver in an SO- 8 surface mount package. It consist of two outputs that provide square waves of opposite phase. The liquid CRYSTAL shutter is connected between the two outputs. Its equivalent load can be approximated as a resistor in parallel with a capacitor. Minimum resistance is 1.0MΩ and maximum capacitance is 0.1µF.
Features ❏ HVCMOS TECHNOLOGY for high performance ❏ Logic-selectable output voltage ❏ 100nF drive capability ❏ Up to 90VP-P ❏ 25µs response time
These surface mount CRYSTAL units are ideally suited for clock signal generating sources for CPUs for power trains and safety control devices requiring extremely high reliability as an electronic part used in a car. This CRYSTAL unit can meet requirement starting from a low frequency 5MHz.
■ Features ● This CRYSTAL unit exhibit stabilized startup characteristic even under extremely severe environmental conditions. ● This CRYSTAL unit is provided with superior environmental performance including heat resistance, vibration resistance, impact resistance, etc. ● Products that are lead-free. These can meet the requirements of re-flow profiling using lead-free solder.
HC49-4H CRYSTALs share the same base outline as the industry standard HC49 CRYSTAL. The CRYSTAL uses at AT-cut strip CRYSTAL with an hermetically sealed can. HC49-4H CRYSTALs provide a low cost source of system clock frequency.
• Low-cost, industry-standard CRYSTAL unit
• AT-Cut strip CRYSTAL with hermetically sealed can
The HC49LD series is a miniature AT or BT cut strip resonator CRYSTAL housed in low profile for surface mounting. The parts present a proven metal package TECHNOLOGY with a precision molded base and universal contact configuration.
The MC12061 is for use with an external CRYSTAL to form a CRYSTAL controlled oscillator. In addition to the fundamental series mode CRYSTAL, two bypass capacitors are required (plus usual power supply pin bypass capacitors). Translators are provided internally for MECL and TTL outputs.
• Frequency Range = 2.0 to 20 MHz • Temperature Range = 0 to + 70°C • Single Supply Operation: +5.0 Vdc or –5.2 Vdc • Three Outputs Available: 1. Complementary Sine Wave (600 mVpp typ) 2. Complementary MECL 3. Single Ended TTL