LC72121 Sanyo Semiconductor Corporation, LC72121 Datasheet
LC72121
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LC72121 Summary of contents
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... Ordering number : EN5815B Overview The LC72121 and the LC72121M and the LC72121V are high input sensitivity (20 mVrms at 130 MHz) PLL frequency synthesizers for 3 V systems. These ICs are serial data (CCB) compatible with the LC72131, and feature the improved input sensitivity and lower spurious radiation (provided by a redesigned ground system) required in high-performance AM/FM tuners ...
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... Package Dimensions unit: mm 3059-DIP22S [LC72121 21.2 0.95 0.48 1.78 1.7 Pin Assignments LC72121, 72121M, 72121V unit: mm 3112-MFP24S 24 1 SANYO: DIP22S unit: mm 3175A-SSOP24 [LC72121M 0.15 12.6 0.35 1.0 0.8 SANYO: MFP24S [LC72121V 0.15 8.0 SANYO: SSOP24 0.22 0.65 0.43 Top view No. 5815-2/23 ...
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... Block Diagram LC72121, 72121M, 72121V No. 5815-3/23 ...
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... Note: Recommended value for CI for the crystal oscillator element: CI ≤ 120Ω (4.5MHz), CI ≤ 70Ω (7.2MHz) Electrical Characteristics in the Allowable Operating Ranges Parameter Internal feedback resistance Internal pull-down resistance Hysteresis Output high-level voltage LC72121, 72121M, 72121V = SSd SSa SSX ...
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... XIN 1 1 Xtal XOUT 22 24 Local FMIN 16 17 oscillator signal input Local AMIN 15 16 oscillator signal input LC72121, 72121M, 72121V Symbol Conditions BO1 to BO4, IO1, IO2 BO1 to BO4, IO1, IO2 DO ...
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... V) DD • The power on reset circuit operates when power is first applied. • Ground for the crystal oscillator circuit • Ground for the low-pass filter MOS transistor • Ground for the LC72121 digital systems other than those that use SSa SSX • ...
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... IN2 (92 OUT (A2 Normally high Normally low LC72121, 72121M, 72121V Address • Control data input (serial data input) mode • 24 bits of data are input • See the “DI Control Data (serial data input)” section for details on the content of the input data. • ...
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... Structure of the DI Control Data (serial data input) • IN1 mode • IN2 mode LC72121, 72121M, 72121V No. 5815-8/23 ...
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... Determines the IF counter measurement time. IF counter control data GT1 3 CTE 0 GT0, GT1 See the “Structure of the IF Counter” section for details. LC72121, 72121M, 72121V Function (* : don’t care) SNS LSB Set divisor (N) Actual divisor * P0 272 to 65535 Twice the set value 1 ...
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... When the PLL is unlocked, the DO pin goes low and UL in the serial data output is set to 0. • Controls the phase comparator dead zone DZ1 0 Phase comparator control data 8 0 DZ0, DZ1 1 1 Dead zone width: DZA < DZB < DZC < DZD LC72121, 72121M, 72121V Function DOC0 DO pin state 0 0 Open 0 1 Low when the PLL is unlocked 1 0 ...
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... UL IF counter binary • Indicates the value of the IF counter (20-bit binary counter). data 3 C19 MSB of the binary counter C0 LSB of the binary counter C19 to C0 LC72121, 72121M, 72121V Function Normal operation Forced to low Function Related data BO1 Related data IOC1 ...
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... CL: Normally high • CL: Normally low Serial Data Output (Out • CL: Normally high • CL: Normally low Note: The data conversion times (t and n-channel open-drain circuit. LC72121, 72121M, 72121V ≥ 0.75 µ < 0.75 µ ≥ 0.75 µ ...
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... DO Data output time t DO LC72121, 72121M, 72121V When CL is Stopped at the Low Level When CL is Stopped at the High Level Conditions These values differ depending on the value of the pull-up resistor used and the printed circuit board capacitance. Ratings Unit ...
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... For MW with a step size of 9 kHz (DVS = 0, SNS = 0: AMIN low-speed operation selected 1008 kHz (IF +450 kHz) WM VCO = 1458 kHz PLL fref =9 kHz ( 1458 (MW VCO) 9 kHz (fref) = 162 LC72121, 72121M, 72121V Set divisor Actual divisor 272 to 65535 Twice the set value ...
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... Structure of the IF Counter The LC72121 IF counter is a 20-bit binary counter, and takes the IF signal from the IFIN pin as its input. The result of the count can be read out serially, MSB first, from the DO pin. Measurement time GT1 GT0 Measurement time (GT ...
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... IF counting only are subject to incorrect stopping at points where there is no station due to IF buffer leakage. Note that the LC72121 input sensitivity can be controlled with the IFS bit in the serial data. Reduced sensitivity mode (IFS = 0) must be selected when this IC is used in conjunction with that does not provide an SD output and auto-search is implemented using only IF counting ...
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... Figure 1 Unlocked State Detection Timing For example, if fref is 1 kHz (a period of 1 ms) applications must wait at least 2 ms after the divisor N is changed before performing a locked/unlocked check. LC72121, 72121M, 72121V Figure 2 Circuit Structure No. 5815-17/23 ...
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... N. However, in this case also, even more reliable recognition of the locked state can be achieved by performing several checks of the state and requiring that the locked state be detected sequentially. LC72121, 72121M, 72121V Figure 3 Combining with Software Divisor N changed (data input) Wait at least 2 reference frequency periods ...
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... SSa current fluctuations in the time base pin to prevent degradation of the low-pass filter characteristics. Pin States after a Power on Reset LC72121, 72121M, 72121V ) and the ground for the SSd No. 5815-19/23 ...
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... Sample Application Circuit (Using the DIP22S package) LC72121, 72121M, 72121V Since this is a high-impedance circuit susceptible to noise. Therefore, lines in the printed circuit board pattern should be made as short as possible and it should be surrounded by the ground pattern. No. 5815-20/23 ...
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... IF counter buffer output and execute the IF count only if there signal. Auto- search techniques that only use the IF counter are subject to incorrect stopping at points where there is no station due to IF buffer leakage. LC72121, 72121M, 72121V Charge pump Dead zone ON/ON – ...
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... LC72131, which is a 5-V system. This means that since the loop gain is reduced, the loop filter constants, the lock time (SD wait time), and other related parameters must be reevaluated in the end product design. LC72121, 72121M, 72121V and V pins for noise exclusion. These capacitors must be ...
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... SANYO believes information herein is accurate and reliable, but no guarantees are made or implied regarding its use or any infringements of intellectual property rights or other rights of third parties. This catalog provides information as of January, 2003. Specifications and information herein are subject to change without notice. LC72121, 72121M, 72121V PS No. 5815-23/23 ...