DESCRIPTIO APPLICATIO S. U Typical Distribution of Frequency Error, T A = 25 C TYPICAL APPLICATIO. LTC6905-XXX Series

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1 FEATRES No External Components to Set Frequency Frequency Error: ±.% Typical Fast Start-p Time: µs Typical ±ppm/ C Temperature Stability Includes Output Enable Includes Frequency Divide by, or Rise Time:.ns, C L = pf Timing Jitter: <.8% Typical Duty Cycle: % ±.% I S = 8mA Typical (f OSC = MHz, C L = pf) CMOS Output Drives 6Ω Load Single Supply.7V to.v Low Profile (mm) ThinSOT TM Package APPLICATIO S Data Clocks for High Reliability Applications High Vibration, High Acceleration Environments Replacement for Fixed Crystal and Ceramic Oscillators, LTC and LT are registered trademarks of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by.s. Patents, including 66, 687. DESCRIPTIO LTC69-XXX Series Fixed Frequency SOT- Oscillator The LTC 69-XXX series are precision, fixed frequency silicon oscillators designed to minimize board space while maximizing accuracy and ease of use. Programmed at the factory to a fixed frequency, the LTC69-XXX series of parts need no external trim components. An internal three-state divider allows for division of the master clock by, or, providing frequencies (for each device). The LTC69-XXX series operate with a single.7v to.v power supply and provide a rail-to-rail, % duty cycle, square wave output. The OE pin will disable the output when brought low and synchronously enable the output when brought high, avoiding pulse slivers. The four products of the LTC69-XXX family are: LTC69-: f OSC = MHz, 66.7MHz,.MHz LTC69-: f OSC = MHz, MHz, MHz LTC69-96: f OSC = 96MHz, 8MHz, MHz LTC69-8: f OSC = 8MHz, MHz, MHz The LTC69-XXX series of parts provides a factory trim option to modify the divider ratios from,, to 8, 6,. A second trim option allows for additional master clock frequencies. For the alternate divider ratios and unlisted frequencies, contact LTC marketing. TYPICAL APPLICATIO Typical Distribution of Frequency Error, T A = C Basic Connection V S =.µf V + OT LTC69- OE 69x TA f OSC = MHz OPEN NITS... % FREQENCY ERROR 69x TA 69xfa

2 LTC69-XXX Series ABSOLTE AXI RATI GS (Note ) W W W Supply Voltage (V + ) to.... to 6V to.... to (V + +.) OE to.... to (V + +.) Output Short-Circuit Duration (Note 6)... Indefinite Operating Temperature Range (Note 8) LTC69C... C to 8 C LTC69I... C to 8 C LTC69H... C to C Specified Temperature Range (Note 8) LTC69C... C to 7 C LTC69I... C to 8 C LTC69H... C to C Storage Temperature Range... 6 C to C Lead Temperature (Soldering, sec)... C W PACKAGE/ORDER I FOR ATIO V + OE ORDER PART NMBER LTC69CS- LTC69IS- LTC69HS- LTC69CS- LTC69IS- LTC69HS- LTC69CS-96 LTC69IS-96 LTC69HS-96 LTC69CS-8 LTC69IS-8 LTC69HS-8 TOP VIEW S PACKAGE -LEAD PLASTIC SOT- T JMAX = C, θ JA = C/W OT S PART MARKING* LTBPM LTBPM LTBPM LTBPK LTBPK LTBPK LTBPJ LTBPJ LTBPJ LTBPH LTBPH LTBPH Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: *The temperature grade is identified by a label on the shipping container. ELECTRICAL CHARACTERISTICS The denotes the specifications which apply over the full specified temperature range, otherwise specifications are at T A = C or as noted. OE = = V +, V + =.7V to.6v, R L = k, C L = pf, unless otherwise noted. All voltages are with respect to. SYMBOL PARAMETER CONDITIONS MIN TYP MAX NITS f Frequency Accuracy (Notes, 7) LTC69C-XXX T A = C, V + = ±. ±. % C < T A < 7 C ±. % LTC69I-XXX C < T A < 8 C ±.8 % C < T A < 8 C ±.9 % LTC69H-XXX C < T A < C ±. % C < T A < C ±.9 % V + = V ±. % f/ T Freq Drift Over Temp (Note ) ± ppm/ C f/ V Freq Drift Over Supply (Notes, 7) V + =.7V to.6v. %/V Timing Jitter (Note ).8 % Long-Term Stability of Output Frequency ppm/ khr 69xfa

3 ELECTRICAL CHARACTERISTICS LTC69-XXX Series The denotes the specifications which apply over the full specified temperature range, otherwise specifications are at T A = C or as noted. OE = = V +, V + =.7V to.6v, R L = k, C L = pf, unless otherwise noted. All voltages are with respect to. SYMBOL PARAMETER CONDITIONS MIN TYP MAX NITS Duty Cycle = V 7.. % V + Operating Supply Range.7. V I S Power Supply Current = V + ( ), V + =.6V LTC69- ma LTC69-8 ma LTC ma LTC ma = ( ), V + =.6V LTC69-8 ma LTC69-7 ma LTC ma LTC ma V IH High Level or OE Pins Input Voltage V +. V V IL Low Level or OE Pins Input Voltage. V I Input Current (Note ) = V + V + =.V µa = V V + =.V µa I OE OE Input Current (Note ) OE = V + V + =.V µa OE = V V + =.V µa V OH High Level Output Voltage (Note ) V + =.V I OH = ma.. V I OH = ma.. V V + =.7V I OH = ma..6 V I OH = ma.. V V OL Low Level Output Voltage (Note ) V + =.V I OL = ma.. V I OL = ma.. V V + =.7V I OL = ma.. V I OL = ma.. V t r, t f OT Rise/Fall Time (Note ). ns Note : Absolute Maximum Ratings are those values beyond which the life of the device may be impaired. Note : Frequency accuracy is tested with = V + ( ). Other divide ratios are guaranteed by design. Note : Jitter is the ratio of the peak-to-peak distribution of the period to the mean of the period. This specification is based on characterization and is not % tested. Note : To conform with the Logic IC Standard convention, current out of a pin is arbitrarily given as a negative value. Note : Output rise and fall times are measured between the % and 9% power supply levels. Note 6: A heat sink may be required to keep the junction temperature below the absolute maximum when the output is shorted indefinitely. Note 7: The LTC69 is optimized for the performance with a power supply voltage. Refer to Typical Performance Characteristics curves in this data sheet for additional information regarding the LTC69 voltage coefficient, especially between.v and.v. Please consult LTC Marketing for parts optimized for V operation. Note 8: The LTC69C-XXX is guaranteed functional over the operating temperature range and is guaranteed to meet specified performance from C to 7 C. The LTC69C-XXX is designed, characterized and expected to meet specified performance from C to 8 C but is not tested or QA sampled at these temperatures. The LTC69I-XXX is guaranteed to meet specified performance from C to 8 C. 69xfa

4 LTC69-XXX Series TYPICAL PERFOR A CE CHARACTERISTICS W SPPLY CRRENT (ma) Supply Current vs Frequency.V.7V FREQENCY (MHz) FREQENCY ERROR (%)..... O.. Frequency Error vs Supply Voltage LTC69-.. SPPLY VOLTAGE (V) LTC69- LTC69-96 LTC x G 69x G9 OTPT RESISTANCE (Ω) R OT vs V + JITTER (%) Jitter vs Frequency PERCENTAGE ERROR (%) Frequency vs Temperature.... SPPLY VOLTAGE (V) FREQENCY (MHz). 6 8 TEMPERATRE ( C) 69x G 69x G 69x G8 LTC69-8 Output Operating at MHz, V S = LTC69- Output Operating at MHz, V S =.7V/.7V/ ns/ 69x G6.ns/ 69x G7 69xfa

5 PI F CTIO S V + (Pin ): Voltage Supply (.7V V +.V). This supply must be kept free from noise and ripple. It should be bypassed directly to the (Pin ) with a.µf capacitor or higher. (Pin ): Ground. Should be tied to a ground plane for best performance. OE (Pin ): Output Enable. Pull to V+ or leave floating to enable the output driver (Pin ). Pull low to disable the output. The output is disabled asynchronously. Pulling OE pin low will immediately disable the output. Pulling the OE pin high will bring the output high on the next low to high transition of the clock. This eliminates pulse slivers. (Pin ): Divider-Setting Input. This three-state input selects among three divider settings. Pin should be tied LTC69-XXX Series to V + for the setting, the highest frequency range. Floating Pin divides the master oscillator by. Pin should be tied to for the setting, the lowest frequency range. To detect a floating pin, the LTC69 attempts to pull the pin toward midsupply. This is realized with two internal current sources, one tied to V + and Pin and the other one tied to ground and Pin. Therefore, driving the pin high requires sourcing approximately µa. Likewise, driving low requires sinking µa. When Pin is floated, it should be bypassed by a nf capacitor to ground or it should be surrounded by a ground shield to prevent excessive coupling from other PCB traces. OT (Pin ): Oscillator Output. This pin can drive kω and/or pf loads. For heavier loads, refer to the Applications Information section. BLOCK DIAGRA W V + + V RES = V ±% (V + V SET ) OE PROGRAMMABLE IDER (N =, OR ) f OSC = f MO N OT + V BIAS + R SET I RES GAIN = I RES MASTER OSCILLATOR f MO IDER SELECT THREE-STATE INPT DETECT V + µa µa 69x BD Table. LTC69-XXX Frequency Settings SETTING LTC69- LTC69- LTC69-96 LTC69-8 V+.MHz MHz 96MHz 8MHz OPEN 66.66MHz MHz 8MHz MHz.MHz MHz MHz MHz 69xfa

6 LTC69-XXX Series APPLICATIO S I FOR ATIO START-P TIME 6 W The start-up and settling time to within % of the final frequency is typically µs. MAXIMM OTPT LOAD The LTC69 output (Pin ) can drive a capacitive load (C LOAD ) of pf or more. Performance driving a C LOAD greater than pf depends on the oscillator s frequency (f OSC ) and output resistance (R OT ). The output rise time or fall time due to R OT and C LOAD is equal to. R OT C LOAD (from % to 9% of the rise or fall transition). If the total output rise time plus fall time is arbitrarily specified to be equal to or less than % of the oscillator s period (/ f OSC ), then the maximum output C LOAD in picofarads (pf) should be equal to or less than [/(R OT f OSC )] (R OT in ohms and f OSC in MHz). Example: An LTC69- is operating with a power supply and is set for a f OSC = MHz. R OT with V + = is 7Ω (using the R OT vs V + graph in the Typical Performance Characteristics). The maximum output C LOAD should be equal to or less than [/(7 )] =.6pF. The lowest resistive load Pin can drive can be calculated using the minimum high level output voltage in the Electrical Characteristics. With a V + equal to.v and ma output current, the minimum high level output voltage is.v and the lowest resistive load Pin can drive is.k (.V/mA). With a V + equal to.7v and ma output current, the minimum high level output voltage is.v and the lowest resistive load Pin can drive is 6Ω (.V/mA). FREQENCY ACCRACY AND POWER SPPLY NOISE The frequency accuracy of the LTC69 may be affected when its power supply generates noise with frequency contents equal to f MO /6 or its multiples. f MO is the highest frequency for an LTC69-XXX which is with = V + ( ). This is also the frequency indicated in the part number (i.e., LTC69-, f MO = MHz). f MO /6 is the master oscillator control loop frequency. For example, if the LTC69-8 with a master oscillator frequency of 8MHz is powered by a switching regulator, then the oscillator frequency may show an additional error if the switching frequency is.mhz (8MHz/6). The magnitude of this effect is heavily dependent on supply bypass and routing. JITTER AND POWER SPPLY NOISE If the LTC69 is powered by a supply that has frequency content equal to the output frequency then the output jitter may increase. In addition, power supply ripple in excess of mv at any frequency may increase jitter. Higher divide ratios will result in lower percentage jitter. For example, jitter percentage of the LTC69-8 operating at MHz is lower than for the same part operating at 8MHz. Please consult the Jitter vs Frequency graph showing jitter at various divider ratios. LTC69 SGGESTED CRITICAL COMPONENT LAYOT In order to provide the specified performance, it is required that the supply bypass capacitor be placed as close as possible to the LTC69. The following additional rules should be followed for best performance: ) The bypass capacitor must be placed as close as possible to the LTC69, and no vias should be placed between the capacitor and the LTC69. The bypass capacitor must be on the same side of the circuit board as the LTC69. ) If a ground plane is used, the connection of the LTC69 to the ground plane should be as close as possible to the LTC69 pin and should be composed of multiple, high current capacity vias. C LTC69 69x F Figure. LTC69 Suggested Critical Component Layout 69xfa

7 LTC69-XXX Series PACKAGE DESCRIPTIO S Package -Lead Plastic TSOT- (Reference LTC DWG # -8-6).6 MAX.9 REF.9 BSC (NOTE ). REF.8 MAX.6 REF. MIN.8 BSC..7 (NOTE ) PIN ONE RECOMMENDED SOLDER PAD LAYOT PER IPC CALCLATOR.9 BSC.. TYP PLCS (NOTE ).8.9. BSC DATM A. MAX.... REF.9..9 BSC NOTE: (NOTE ) S TSOT-. DIMENSIONS ARE IN MILLIMETERS. DRAWING NOT TO SCALE. DIMENSIONS ARE INCLSIVE OF PLATING. DIMENSIONS ARE EXCLSIVE OF MOLD FLASH AND METAL BRR. MOLD FLASH SHALL NOT EXCEED.mm 6. JEDEC PACKAGE REFERENCE IS MO-9 Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. 69xfa 7

8 LTC69-XXX Series TYPICAL APPLICATIO S Driving a Ω Cable with the LTC69.µF V + OT LTC69-XXX 9Ω Ω CABLE V OT Ω OE 69x TA Driving the Pin Without Three-State Buffers A B.µF V + OT LTC69-XXX A k OE 69x TA B k RELATED PARTS PART NMBER DESCRIPTION COMMENTS LTC799 khz to MHz ThinSOT Oscillator Single Output, High Frequency Operation LTC69 khz to MHz ThinSOT Oscillator Single Output Lower Power LTC69 Multiphase Oscillator with Spread Spectrum Modulation -, - or -Phase Outputs LTC69/LTC69 khz to 68MHz Serial Port Programmable Oscillator -Wire or I C TM Programmable LTC69 7MHz to 7MHz Resistor Set ThinSOT Oscillator Single Resistor Sets Frequency LTC696 Micropower, khz to MHz Resistor Set ThinSOT Oscillator ltralow Power, Resistor Sets Frequency 8 LT/LT REV A PRINTED IN SA Linear Technology Corporation 6 McCarthy Blvd., Milpitas, CA 9-77 (8) -9 FAX: (8) -7 LINEAR TECHNOLOGY CORPORATION 69xfa