LTC6909 Linear Dimensions Semiconductor, LTC6909 Datasheet
LTC6909
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LTC6909 Summary of contents
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... OUT where The LTC6909 can be used in applications requiring only one or two output phases. Alternatively, the LTC6908 family of parts provides the same two output signals but in a smaller SOT-23 or 2mm × 3mm DFN package. The LTC6908-1 provides complimentary (180° ...
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... LTC6909C ............................................ –40°C to 85°C LTC6909I.............................................. –40°C to 85°C LTC6909H .......................................... –40°C to 125°C Specifi ed Temperature Range (Note 3) LTC6909C ................................................ 0°C to 70°C LTC6909I.............................................. –40°C to 85°C LTC6909H .......................................... –40°C to 125°C Junction Temperature ........................................... 150°C Storage Temperature Range .................. –65°C to 150°C Lead Temperature (Soldering, 10 sec) .................. 300° ...
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... V = 2.7V Note 3: The LTC6909C is guaranteed to meet specifi ed performance from 0°C to 70°C. The LTC6909C is designed, characterized and expected to meet specifi ed performance from –40°C to 85°C but is not tested or QA sampled at these temperatures. The LTC6909I is guaranteed to meet specifi ed performance from –40°C to 85°C. The LTC6909H is guaranteed to meet specifi ...
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... LTC6909 www.DataSheet4U.com ELECTRICAL CHARACTERISTICS Note the internal master oscillator frequency. The output MASTER frequency is f /PH. The PH value is determined by the connections MASTER of the PH0, PH1 and PH2 pins as described in the Applications Information section. Note 5: Frequency accuracy is defi ned as the deviation from the f equation 20MHz • ...
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... SUPPLY VOLTAGE (V) 6909 G07 SET C = 5pF LOAD 500mV/DIV + V = 2.7V, DIV = 5V, DIV = 2.7V, DIV = 8 100k 1M 10M R (Ω) SET 6909 G10 50ns/DIV 6909 G12 LTC6909 Output Rise/Fall Time vs Supply Voltage 4 5pF LOAD T = 25°C 4 LOAD 3.5 3.0 RISE TIME 2.5 2.0 FALL TIME 1.5 1.0 0.5 0 2.7 3.2 3.7 4.2 5 SUPPLY VOLTAGE (V) 6909 G08 Output Operating at 3 ...
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... Tying one of the OUT active outputs to the MOD pin turns the modulation off. To detect a fl oating MOD pin, the LTC6909 attempts to pull the pin to the midsupply point. This is realized with two internal current sources, one tied to V and the other one tied to GND and MOD. Therefore, driv- ing the MOD pin high requires sourcing approximately 2μ ...
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... V – POLE SET I MASTER LPF R SET I REF MDAC PSEUDORANDOM CODE GENERATOR WHEN A CLOCK SIGNAL IS PRESENT AT THE MOD PIN INPUT, THE MODULATION IS DISABLED LTC6909 + PH0 PH1 PH2 20MHz • 10k/R SET DRIVER DRIVER OUT DRIVER OUTPUT PHASING DRIVER ...
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... Output Frequency and Confi gurations resistor. When SET The output frequency of the LTC6909 is set by the R current is resistor value and the connections of the PH0, PH1 and MASTER – 10%) PH2 logic input pins. The following formula defi nes the ...
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... ADJACENT OUTPUTS ARE PHASE SHIFTED BY 120° MASTER /4 ADJACENT OUTPUTS ARE PHASE SHIFTED BY 90° MASTER /5 ADJACENT OUTPUTS ARE PHASE SHIFTED BY 72° MASTER /6 ADJACENT OUTPUTS ARE PHASE SHIFTED BY 60° MASTER Figure 2a. Output Waveforms for Different PH Settings LTC6909 6909 F02a 6909f 9 ...
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... LTC6909 www.DataSheet4U.com OPERATION MASTER OSCILLATOR PH2 - PH1 - PH0 = 110 OUTPUT MASTER OUT1 OUT2 OUT3 OUT4 OUT5 OUT6 OUT7 OUT8 Hi-Z PH2 - PH1 - PH0 = 111 OUTPUT MASTER OUT1 OUT2 OUT3 OUT4 OUT5 OUT6 OUT7 OUT8 10 /7 ADJACENT OUTPUTS ARE PHASE SHIFTED BY 51.43° ...
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... OPERATION Spread Spectrum Frequency Modulation The LTC6909 can operate with spread spectrum frequency modulation (SSFM). In this mode, the oscillator’s frequency is modulated by a pseudorandom noise (PRN) signal to spread the oscillator’s energy over a wide frequency band. This spreading decreases the peak electromagnetic radiation levels and improves electromanetic compatibility (EMC) performance ...
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... V I CONTROL f = 10k • (20MHz/1.13V) • I MASTER Figure 4. Current Controlled Oscillator Figure 5 shows the LTC6909 confi gured age source is connected in series with an external 10k resistor. The master oscillator frequency, f vary with V , that is the voltage source connected CONTROL + between V and the SET pin ...
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... Depending on the switching regulator’s inductor design and triangle wave frequency, it may even result in an audible noise. The LTC6909 uses a pseudorandom noise-like signal oscilloscope, it looks essentially noise-like of even amplitude. The signal is broadband and any mixing issues are eliminated ...
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... The LTC6909’s accuracy is affected as described above + by supply ripple on the V A pin only. The V sentially insensitive to supply ripple. The V the power for the analog section of the LTC6909 and its current is largely constant for a given R + value. The V D pin supplies the digital section including ...
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... Powering up and down complex multiphase switching regulator circuits is always chaotic and can have serious system consequences not done carefully. In addition to the LTC6909’s muting of the outputs to ensure fi rst cycle accuracy, the PH0-PH1-PH2 codes 000 (all outputs are SET DIRECT, LOW IMPEDANCE ...
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... There are several parts available that combine a comparator with a reference to fulfi ll this function. The + V 0.1μF Figure 8. Adding a UVLO Feature to the LTC6909. In This Example, the LTC6909 Is in 4-Phase Mode + for a V > ≈2.5V (PHx = 011) and the Outputs Are All High Impedance for V 16 LTC6909 does not have its own internal UVLO ...
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... PGOOD PGOOD MPGM RUN 10μF 25V COMP ×2 INTV CC DRV CC 392k SGND *C OPTIONAL TO REDUCE ANY LC RINGING. IN NOT NEEDED FOR LOW INDUCTANCE PLANE CONNECTION LTC6909 V = 0.6V OUT CLOCK SYNC 0° PHASE N = NUMBER OF PHASES TRACK/SS CONTROL V PLLIN TRACK/ OUT 220pF V FB 22μF MARG0 6 ...
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... V 0.1μF 100kHz 15 LPB SINE WAVE 14 OUTPUT NC 16.2k 13 INVB 12 20k 16. 6909 TA04 14 OUTPUT PHASES (OUTPUTS SHIFTED BY 25.71 DEGREES) LTC6909 + V D OUT1 GND OUT2 + V A OUT3 SET OUT4 R SET PH0 OUT5 PH1 OUT6 PH2 OUT7 MOD OUT8 500mV/DIV 2μs/DIV ...
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... TYP 0.53 0.152 (.021 .006) (.043) DETAIL “A” MAX SEATING PLANE 0.17 – 0.27 (.007 – .011) TYP LTC6909 4.039 0.102 (.159 .004) (NOTE 3) 0.280 0.076 (.011 .003) 16151413121110 9 REF 3.00 0.102 (.118 .004) (NOTE ...
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... Dual Output ThinSOT Oscillator, Resistor Set LTC6930-XXX Fixed Frequency Oscillator, 32.768kHz to 8.192MHz ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● Providing an 8-Phase Synchronizing Clock to LTM Modules LTC6909 + D OUT1 OUT2 + A OUT3 OUT4 OUT5 OUT6 ...