SP8855 Mitel, SP8855 Datasheet
SP8855
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SP8855 Summary of contents
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... Supersedes version in January 1996 Professional Products IC Hanbook, HB2480-3.0 The SP8855E is one of a family of parallel load synthesisers containing all the elements apart from the loop amplifier to fabricate a PLL synthesis loop. Other devices in the series are the SP8852E which is a fully programmable device requiring two 16 bit words to set the RF and reference ...
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... SP8855E 2 DETECTOR PHASE ...
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... These pins set the Reference divider ratio R. Open circuit = HI. When this pin is HI the phase detector output is enable. Open circuit = HI. These pins set the charge pump current multiplication factor (see table 1). Open circuit = HI. SP8855E sets the charge pump output current CC and F ...
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... SP8855E ELECTRICAL CHARACTERISTICS Guaranteed over the full temperature and supply voltage range (unless otherwise stated) Temperature T for KG parts -55 C and +100 C, amb MA part -55 C and +125 C Supply Voltage = 4.75V and 5.25V Characteristics Pin Supply current15 input sensitivity 13 division ratio ...
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... GUARANTEED OPERTAING WINDOW -5 -10 -20 -30 100MHz +j0.5 +j0.2 0.2 0 1.1GHz -j0.2 -j0.5 Fig. 4 R.F. input impedance TYPICAL OVERLOAD TYPICAL SENSITIVITY 2.7GHz 1GHz 2GHz INPUT DRIVE REQUIREMENTS Fig. 3 SP8855E +j1 +j2 0.5 1 2.5GHz -j2 -j1 SP8855E OPERATING AREA FOR 'IG' PARTS ONLY 2.8GHz 10GHz 50MHz 5 ...
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... Fig. 5 Typical application diagram Phase Comparator and Charge pump The SP8855E has a digital phase/frequency comparator driving a charge pump with programmable current output. The charge pump current level at the minimum gain setting is approximately equal to the current fed into the R pin 19 and can be increased by programming pins 40 and 41 according to Table times ...
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... REFERENCE DIVIDER PROGRAMMING PIN ALLOCATION COUNTER RF REFERENCE DIVIDER PROGRAMMING PIN ALLOCATION Fig. 6 Programming data format SP8855E PIN PIN BIT A COUNTER 7 ...
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... SP8855E 40k 5k 40k INPUT Fig and reference divider programming bits, F enable, control direction and phase detector gain control inputs C-LOCK DETECT (HIGH WHEN LOCKED 50k 100 Fig. 7c Lock detect decouple R set 19 Vcc CHARGE PUMP CURRENT SOURCES 130 Fig ...
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... SP8855E. All signals such as the programming inputs reference in and the connections to the op-amp are best taken through the pc board adjacent to the SP8855E with through plated holes allowing connections to remote points without fragmenting the earth plane. Programming inputs The input pins are designed to be compatible with TTL or CMOS logic with a switching threshold set at about 2 ...
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... SP8855E If a faster indication is required, comparable with the loop lock up time, the capacitor will need to be 2-3 times smaller than the time constant calculation suggests. The time to respond to an out of lock conditions is 2-3 times less than that required to indicate lock. Charge pump circuit ...
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... To obtain the lowest possible phase noise from the SP8855E it is best to use the highest possible reference input frequency and to divide this down internally to obtain the required frequency at the phase detector ...
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... SP8855E From equation tan 45 + cos 45 = 0.4142 = 3 100kHz 659 From equation (100kHz 3.844 Using these values in equation 10MHz 100 100kHz) 12 Where A is 628319 -9 x 659 x 10 1/2 [A] 2 Substituting for 100kHz ...
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... Mitel. This publication is issued to provide information only and (unless agreed by Mitel in writing) may not be used, applied or reproduced for any purpose nor form part of any order or contract nor to be regarded as a representation relating to the products or services concerned. The products, their specifications, services and other information appearing in this publication are subject to change by Mitel without notice. No warranty or guarantee express or implied is made regarding the capability, performance or suitability of any product or service. Information concerning possible methods of use is provided as a guide only and does not constitute any guarantee that such methods of use will be satisfactory in a specifi ...