VT73227 VCXO (Voltage-Controlled Crystal Oscillator) 27 MHz 3.3V Applications •= Set-top boxes •= Oscillator replacement •= Telecom switching •= MPEG Video clock source General Description The Vaishali VT73227 is a single-chip, low-jitter Voltage-Controlled-Crystal-Oscillator. The device accepts a 27 MHz, 20 pF (pull range of 200 ppm) crystal input, and produces a low jitter output at the same frequency. A 0 to 3.0V control signal is used to fine tune the output clock frequency in the ±100ppm range. Features •= 3.3V operating voltage •= Uses inexpensive pullable crystal •= 12mA drive capability at TTL levels •= On-chip oscillator with 200 ppm pull range (±100 ppm) •= 8 pin SOIC package Figure 1. Functional Block Diagram VDD1 VDD2 Load Cap Control VIN X2 Output Buffer 27 MHz Pullable Crystal Load Caps CLK1 Oscillator X1 GND2 GND1 2001-04-02 Page 1 MDST-0006-03 Vaishali Semiconductor 1300 White Oaks Road, Ste. 200 Campbell CA 95008 Ph. 408.377.6060 Fax 408.377.6063 VT73227 Figure 2. Pin Configuration VT73227 X1 1 8 X2 VDD1 2 7 GND1 VIN 3 6 VDD2 GND2 4 5 CLK 8 pin (150 mil) SOIC Table 1. Pin Description Name Pin # Type Description X1 1 Xi Crystal connection. Connect to a 27 MHz pullable crystal VDD1 2 P Core VDD. Connect to 3.3V VIN 3 I Voltage input to VCXO. Zero to 3.3V signal controls the frequency of the VCXO. GND2 4 P Connect to ground. CLK 5 O Clock output VDD2 6 P Pad driver VDD . Connect to 3.3V GND1 7 P Connect to ground. X2 8 Xi Crystal connection. Connect to a 27 MHz pullable crystal. Legend: I = Input O = Output P = Power supply connection Xi = Crystal connections. Table 2. Absolute Maximum Ratings Parameter Conditions Supply voltage, VDD Referenced to GND Inputs and Clock Outputs Referenced to GND Soldering Temperature Max of 10 seconds Storage temperature Min Typ -0.5 -65 Max Units 7 V VDD+0.5 V 260 °C 150 °C Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. These ratings are stress specifications only and correct functional operation of the device at these or any other conditions above those listed in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect product reliability. Table 3. Operating Conditions Parameter Conditions Min Operating Voltage, VDD 3.15 Input High Voltage, VIH, X1 pin only 2.5 Input Low Voltage, VIL, X1 pin only Operating Temperature 0 Input crystal accuracy VCXO control voltage, VIN 2001-04-02 0 Page 2 Typ 3.3 Max 3.45 Units V V 0.4 V 70 °C ±30 ppm 3.3 V MDST-0006-03 Vaishali Semiconductor 1300 White Oaks Road, Ste. 200 Campbell CA 95008 Ph. 408.377.6060 Fax 408.377.6063 VT73227 Table 4. DC Electrical Characteristics TA = 0°C to +70°C, VDD = 3.15 V to 3.45 V Parameter Condition (1) Min Typ Max 2.4 Units Output High Voltage, VOH IOH=-12mA V Output Low Voltage, VOL IOL=12mA Operating Supply Current, IDD No Load 25 mA Short Circuit Current Each output ±85 mA 7 pF 0.4 Input Capacitance V Note: 1. Typical values are at VDD = 3.3V and 25°C Table 5. AC Electrical Characteristics TA = 0°C to +70°C, VDD = 3.15 V to 3.45 V Symbol Parameter Condition Min Typ Max Units fosc Input Crystal Frequency 27 MHz tr Output Clock Rise Time 0.8 to 2.0V 1.5 ns tf Output Clock Fall Time 2.0 to 0.8V 1.5 ns tod Output Clock Duty Cycle At VDD/2 60 % tjit (pk – pk) Maximum Absolute Jitter 150 ps 40 (Peak to Peak) Output pullability 0V <VIN <3.3V ±100 ppm Note: 1. Typical values are at VDD = 3.3V and 25°C Table 6 Pullable Crystal Specifications Parameter Symbol Value Correlation (Load) Capacitance CL 20pF Capacitance Ratio CO/C1 240 max ESR 50 Ω max Initial Accuracy ±30ppm Temperature and Aging Stability ±50ppm Ordering Information VT73227 Part Number VT73227-S1 VT73227-S1X VT73227-/D 2001-04-02 Marking VT73227-S1 VT73227-S1 - Shipping/Packaging Tubes Tape & Reel Die Page 3 No. of Pins 8 8 Package SOIC SOIC Temperature o o 0 C to +70 C o o 0 C to +70 C o o 0 C to +70 C MDST-0006-03 Vaishali Semiconductor 1300 White Oaks Road, Ste. 200 Campbell CA 95008 Ph. 408.377.6060 Fax 408.377.6063