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| Ordering number : EN5175A CMOS LSI LC72135M PLL Frequency Synthesizer for Electronic Tuning Overview The LC72135M is a PLL frequency synthesizer LSI for tuners in car stereo and similar applications. Highperformance AM/FM tuners can be easily implemented with this product. Functions * High-speed programmable dividers -- FMIN: 10 to 160 MHz ..........pulse swallower (built-in divide-by-two prescaler) -- AMIN: 2 to 40 MHz ..............pulse swallower 0.5 to 10 MHz ...........direct division * IF counter -- HCTR 0.4 to 12 MHz ...........AM/FM IF counter -- LCTR 100 to 500 k Hz.........AM IF counter * Reference frequencies -- Twelve selectable frequencies (4.5 or 7.2 MHz crystal) 1, 3, 5, 9, 10, 3.125, 6.25, 12.5, 15, 25, 50 and 100 kHz * Phase comparator -- Dead zone control -- Unlock detection circuit -- Deadlock clear circuit * Built-in MOS transistor for forming an active low-pass filter * I/O ports -- Dedicated output ports: 4 -- Input or output ports: 1 -- Input ports (LCTR) : 1 -- Support clock time base output * Serial data I/O -- Support CCB format communication with the system controller. * Operating ranges -- Supply voltage........................4.5 to 5.5 V -- Operating temperature............-40 to +85C * Package -- MFP20 Package Dimensions unit: mm 3036B-MFP20 [LC72135M] SANYO: MFP20 * CCB is a trademark of SANYO ELECTRIC CO., LTD. * CCB is SANYO's original bus format and all the bus addresses are controlled by SANYO. Any and all SANYO products described or contained herein do not have specifications that can handle applications that require extremely high levels of reliability, such as life-support systems, aircraft's control systems, or other applications whose failure can be reasonably expected to result in serious physical and/or material damage. Consult with your SANYO representative nearest you before using any SANYO products described or contained herein in such applications. SANYO assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all SANYO products described or contained herein. SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110-8534 JAPAN 83098HA (OT)/22896HA (OT) No. 5175-1/24 LC72135M Pin Assignment No. 5175-2/24 LC72135M Block Diagram No. 5175-3/24 LC72135M Specifications Absolute Maximum Ratings at Ta = 25C, VSS = 0 V Parameter Maximum supply voltage Symbol VDD max VIN1 max Maximum input voltage VIN2 max VIN3 max VO1 max Maximum output voltage VO2 max VO3 max IO1 max Maximum output current IO2 max IO3 max Allowable power dissipation Operating temperature Storage temperature Pd max Topr Tstg VDD CE, CL, DI, AIN XIN, FMIN, AMIN, HCTR, LCTR/I1 IO2 DO XOUT, PD BO1 to BO4, IO2, AOUT BO1 AOUT, DO BO2 to BO4, IO2 Ta 85C Pins Ratings -0.3 to +7.0 -0.3 to +7.0 -0.3 to VDD + 0.3 -0.3 to +15 -0.3 to +7.0 -0.3 to VDD + 0.3 -0.3 to +15 0 to 3.0 0 to 6.0 0 to 10.0 180 -40 to +85 -55 to +125 Unit V V V V V V V mA mA mA mW C C Allowable Operating Ranges at Ta = -40 to +85C, VSS = 0 V Parameter Supply voltage Symbol VDD VIH1 Input high-level voltage VIH2 VIH3 Input low-level voltage Output voltage VIL VO1 VO2 fIN1 fIN2 Input frequency fIN3 fIN4 fIN5 fIN6 VIN1 VIN2-1 VIN2-2 VIN3 Input amplitude VIN4 VIN5-1 VIN5-2 VIN6-1 VIN6-2 Supported crystals Xtal VDD CE, CL, DI LCTR/I1 IO2 CE, CL, DI, IO2, LCTR/I1 DO BO1 to BO4, IO2, AOUT XIN FMIN AMIN AMIN HCTR LCTR/I1 XIN FMIN FMIN AMIN AMIN HCTR HCTR LCTR/I1 LCTR/I1 XIN, XOUT VIN1 VIN2 VIN3, SNS = 1 VIN4, SNS = 0 VIN5 VIN6 fIN1 f = 10 to 130 MHz f = 130 to 160 MHz fIN3, SNS = 1 fIN4, SNS = 0 fIN5, IFS = 1 fIN5, IFS = 0 fIN6, IFS = 1 fIN6, IFS = 0 * Pins Conditions min 4.5 0.7 VDD 0.7 VDD 0.7 VDD 0 0 0 1 10 2 0.5 0.4 100 400 40 70 40 40 40 70 40 70 4.0 typ max 5.5 6.5 VDD 13 0.3 VDD +6.5 +13 8 160 40 10 12 500 1500 1500 1500 1500 1500 1500 1500 1500 1500 8.0 Unit V V V V V V V MHz MHz MHz MHz MHz kHz mVrms mVrms mVrms mVrms mVrms mVrms mVrms mVrms mVrms MHz Note: * Recommended crystal oscillator CI values: CI 120 (For a 4.5 MHz crystal) CI 70 (For a 7.2 MHz crystal) No. 5175-4/24 LC72135M Electrical Characteristics for the Allowable Operating Ranges at Ta = -40 to +85C, VSS = 0 V Parameter Symbol Rf1 Built-in feedback resistance Rf2 Rf3 Rf4 Rf5 Built-in pull-down resistor Hysteresis Output high-level voltage Rpd1 Rpd2 VHIS VOH1 VOL1 VOL2 VOL3 XIN FMIN AMIN HCTR LCTR/I1 FMIN AMIN CE, CL, DI, IO2, LCTR/I1 PD PD BO1 IO = -1 mA IO = 1 mA IO = 0.5 mA IO = 1 mA IO = 1 mA IO = 5 mA IO = 1 mA VOL4 VOL5 IIH1 IIH2 IIH3 Input high-level current IIH4 IIH5 IIH6 IIH7 IIL1 IIL2 Input low-level current IIL3 IIL4 IIL5 IIL6 IIL7 Output off leakage current High-level three-state off leakage current Low-level three-state off leakage current Input capacitance IOFF1 IOFF2 IOFFH IOFFL CIN IDD1 BO2 to BO4, IO2 IO = 5 mA IO = 8 mA AOUT CE, CL, DI LCTR/I1 IO2 XIN FMIN, AMIN HCTR, LCTR/I1 AIN CE, CL, DI LCTR/I1 IO2 XIN FMIN, AMIN HCTR, LCTR/I1 AIN BO1 to BO4, AOUT, IO2 DO PD PD FMIN VDD Xtal = 7.2 MHz, fIN2 = 130 MHz, VIN2 = 40 mVrms PLL block stopped (PLL INHIBIT), Xtal oscillator operating (Xtal = 7.2 MHz) PLL block stopped Xtal oscillator stopped IO = 1 mA, AIN = 1.3 V VI = 6.5 V VI = VDD, L/I1 = 0 VI = 13 V VI = VDD VI = VDD VI = VDD, L/I1 = 1 VI = 6.5 V VI = 0 V VI = 0 V, L/I1 = 0 VI = 0 V VI = 0 V VI = 0 V VI = 0 V, L/I1 = 1 VI = 0 V VO = 13 V VO = 6.5 V VO = VDD VO = 0 V 0.01 0.01 6 5 10 2.0 4.0 8.0 2.0 4.0 8.0 VDD - 1.0 1.0 0.5 1.0 0.2 1.0 0.2 1.0 1.6 0.5 5.0 5.0 5.0 11 22 44 200 5.0 5.0 5.0 11 22 44 200 5.0 5.0 200 200 Pins Conditions min typ 1.0 500 500 250 250 200 200 0.1 VDD max Unit M k k k k k k V V V V V V V V V V V V A A A A A nA A A A A A A nA A A nA nA pF mA Output low-level voltage DO Current drain IDD2 VDD 0.5 mA IDD3 VDD 10 A No. 5175-5/24 LC72135M Pin Functions Symbol Pin No. Type Functions Circuit configuration XIN XOUT 1 20 Xtal OSC * Crystal resonator connection (4.5/7.2 MHz) FMIN 14 Local oscillator signal input * FMIN is selected when the serial data input DVS bit is set to 1. * The input frequency range is from 10 to 160 MHz. * The input signal passes through the internal divide-bytwo prescaler and is input to the swallow counter. * The divisor can be in the range 272 to 65535. However, since the signal has passed through the divide-by-two prescaler, the actual divisor is twice the set value. AMIN 13 Local oscillator signal input * AMIN is selected when the serial data input DVS bit is set to 0. * When the serial data input SNS bit is set to 1: -- The input frequency range is 2 to 40 MHz. -- The signal is directly input to the swallow counter. -- The divisor can be in the range 272 to 65535, and the divisor used will be the value set. * When the serial data input SNS bit is set to 0: -- The input frequency range is 0.5 to 10 MHz. -- The signal is directly input to a 12-bit programmable divider. -- The divisor can be in the range 4 to 4095, and the divisor used will be the value set. CE 2 Chip enable Set this pin high when inputting (DI) or outputting (DO) serial data. CL 4 Clock * Used as the synchronization clock when inputting (DI) or outputting (DO) serial data. DI 3 Data input * Inputs serial data transferred from the controller to the LC72135M. DO 5 Data output * Outputs serial data transferred from the LC72135M to the controller. The content of the output data is determined by the serial data DOC0 to DOC2. VDD 15 Power supply * The LC72135M power supply pin (VDD = 4.5 to 5.5 V) * The power on reset circuit operates when power is first applied. Continued on next page. No. 5175-6/24 LC72135M Continued from preceding page. Symbol Pin No. Type Functions Circuit configuration VSS 19 Ground * The LC72135M ground -- BO1 BO2 BO3 BO4 6 7 8 9 Output port * Dedicated output pins * The output states are determined by BO1 to BO4 bits in the serial data. Data: 0 = open, 1 = low * All output ports are set to the open state following a power-on reset. * A time base signal (8 Hz) can be output from the BO1 pin. (When the serial data TBC bit is set to 1.) * Care is required when using the BO1 pin, since it has a higher on impedance that the other output ports (pins BO2 to BO4). IO2 12 I/O port * I/O dual-use pins * The direction (input or output) is determined by bit IOC2 in the serial data. Data: 0 = input port, 1 = output port * When specified for use as input ports: The state of the input pin is transmitted to the controller over the DO pin. Input state: low = 0 data value high = 1 data value * When specified for use as output ports: The output states are determined by the IO2 bit in the serial data. Data: 0 = open, 1 = low * The pin function as input pin following a power-on reset. PD 16 Charge pump output * PLL charge pump output When the frequency generated by dividing the local oscillator frequency by N is higher than the reference frequency, a high level is output from the PD pin. Similarly, when that frequency is lower, a low level is output. The PD pin goes to the high-impedance state when the frequencies match. AIN AOUT 17 18 LPF amplifier transistor * The n-channel MOS transistor used for the PLL active low-pass filter. Continued on next page. No. 5157-7/24 LC72135M Continued from preceding page. Symbol Pin No. Type Functions Circuit configuration HCTR 11 IF counter * HCTR is selected when the LCTS bit in the serial data is set to 0. * Accepts an input in the frequency range 0.4 to 12 MHz. * The input signal is directly transmitted to the IF counter. * The result is output starting the MSB of the IF counter using the DO pin. * Four measurement periods are supported: 4, 8, 32, and 64 ms. IF counter LCTR/I1 10 Input port * LCTR is selected when the LCTS bit in the serial data is set to 1. (Set the L/I1 bit in the serial data to 1 when using the IF counter.) * The input frequency range is 100 to 500 kHz. * The signal is directly transmitted to the IF counter. * The result, starting with the MSB of the IF counter, is output serially through the DO pin. * There are four measurement times: 4, 8, 32, and 64 ms. * If the L/I1 bit in the serial data is set to 0, the LCTR/I1 pin functions as an input port and the state of that input pin is transmitted to the controller from the DO pin. * When the input state is low, the data will be 0, and when the state is high, the data will be 1. No. 5175-8/24 LC72135M Serial Data I/O Methods The LC72135M inputs and outputs data using the Sanyo CCB (computer control bus) audio LSI serial bus format. This LSI adopts an 8-bit address format CCB. I/O mode Address B0 B1 B2 B3 A0 A1 A2 A3 Function * Control data input mode (serial data input) * 24 data bits are input. * See the "DI Control Data (serial data input) Structure" item for details on the meaning of the input data. * Control data input mode (serial data input) * 24 data bits are input. * See the "DI Control Data (serial data input) Structure" item for details on the meaning of the input data. Data output mode (serial data output) * The number of bits output is equal to the number of clock cycles. * See the "DO Output Data (Serial Data Output) Structure" item for details on the meaning of the output data. 1 IN1 (82) 0 0 0 1 0 1 0 0 2 IN2 (92) 1 0 0 1 0 1 0 0 3 OUT (A2) 0 1 0 1 0 1 0 0 No. 5127-9/24 LC72135M 1. DI Control Data (Serial Data Input) Structure * IN1 Mode * IN2 Mode No. 5175-10/24 LC72135M 2. DI Control Data Functions No. Control block/data Functions Related data Programmable divider data * Data that sets the programmable divider. P0 to P15 A binary value in which P15 is the MSB. The LSB changes depending on DVS and SNS. (*: don't care) DVS 1 0 0 (1) DVS, SNS SNS * 1 0 LSB P0 P0 P4 Divisor setting (N) 272 to 65535 272 to 65535 4 to 4095 Actual divisor Twice the value of the setting The value of the setting The value of the setting Note: P0 to P3 are ignored when P4 is the LSB. * Selects the signal input pin (AMIN or FMIN) for the programmable divider, switches the input frequency range. (*: don't care) DVS 1 0 SNS * 1 Input pin FMIN AMIN Input frequency range 10 to 160 MHz 2 to 40 MHz 0 0 AMIN 0.5 to 10 MHz Note: See the "Programmable Divider" item for more information. Reference divider data R0 to R3 * Reference frequency (fref) selection data. R3 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 R2 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 R1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 R0 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 Reference frequency (kHz) 100 50 25 25 12.5 6.25 3.125 3.125 10 9 5 1 3 15 PLL INHIBIT + Xtal OSC STOP (2) 1 1 1 1 PLL INHIBIT Note: PLL INHIBIT The programmable divider block and the IF counter block are stopped, the FMIN, AMIN, HCTR and LCTR pins are set to the pull-down state (ground), and the charge pump goes to the high impedance state. XS * Crystal resonator selection XS = 0: 4.5 MHz XS = 1: 7.2 MHz The 7.2 MHz frequency is selected after the power-on reset. * IF counter measurement start data CTE = 1: Counter start CTE = 0: Counter reset * Determines the IF counter measurement period. GT1 0 0 1 1 (3) IF counter selection data LCTS L/I1 GT0 0 1 0 1 Measurement time (ms) 4 8 32 64 Wait time (ms) 3 to 4 3 to 4 7 to 8 7 to 8 IFS IF counter control data CTE GT0, GT1 Note: See the "IF Counter" item for more information. * Data that specifies the IF counter input pin (and mode). LCTS = 0: HCTR, LCTS = 1: LCTR L/I1 = 0: I1 (Input port), L/I1 = 1: LCTR (AM IF counter) LCTS 0 0 1 1 L/I1 0 1 0 1 LCTR/I1 pin I1 (input port) Off (pulled down) I1 (input port) LCTR (AM IF counter) HCTR pin HCTR (FM/AM IF counter) Off (pulled down) Continued on next page. No. 5175-11/24 LC72135M Continued from preceding page. No. (4) Control block/data I/O port specification data IOC2 Output port data BO1 to BO4, IO2 Functions * Specifies the I/O direction for the bidirectional pin IO2. Data: 0 = input mode, 1 = output mode * Data that determines the output from the BO1 to BO4, and IO2 output ports Data: 0 = open, 1 = low * The data = 0 (open) state is selected after the power-on reset. DO pin control data DOC0, DOC1, DOC2 * Data that determines the DO pin output DOC2 0 0 0 0 1 1 1 1 DOC1 0 0 1 1 0 0 1 1 DOC0 0 1 0 1 0 1 0 1 DO pin state Open Low when the unlock state is detected end-UC*1 Open Open The LCTR/I1 pin state*2 The IO2 pin state*3 Open IOC2 Related data (5) The open state is selected after the power-on reset. Note: 1. end-UC: Check for IF counter measurement completion UL0, UL1, CTE, IOC2 (6) x. When end-UC is set and the IF counter is started (i.e., when CTE is changed from zero to one), the DO pin automatically goes to the open state. When the IF counter measurement completes, the DO pin goes low to indicate the measurement completion state. z Depending on serial data I/O (CE: high) the DO pin goes to the open state. 2. Goes to the open state if the LCTR/I1 pin is set to the AM-IF counter function (L/I1 = 1). 3. Goes to the open state if the I/O pin is specified to be an output port. Caution: The state of the DO pin during a data input period (an IN1 or IN2 mode period with CE high) will be open, regardless of the state of the DO control data (DOC0 to DOC2). Also, the DO pin during a data output period (an OUT mode period with CE high) will output the contents of the internal DO serial data in synchronization with the CL pin signal, regardless of the state of the DO control data (DOC0 to DOC2). Unlock detection data UL0, UL1 * Selects the phase error (oE) detection width for checking PLL lock. A phase error in excess of the specified detection width is seen as an unlocked state. UL1 0 (7) 0 1 1 UL0 0 1 0 1 oE detection width Stopped 0 0.55 s 1.11 s Open oE is output directly oE is extended by 1 to 2 ms oE is extended by 1 to 2 ms Detector output DOC0, DOC1, DOC2 Note: In the unlocked state the DO pin goes low and the UL bit in the serial data becomes zero. Phase comparator control data DZ0, DZ1 * Controls the phase comparator dead zone. DZ1 0 (8) 0 1 1 DZ0 0 1 0 1 DZA DZB DZC DZD Dead zone mode Dead zone widths: DZA < DZB < DZC < DZD (9) Clock time base TBC Charge pump control data DLC Setting TBC to one causes an 8 Hz, 40% duty clock time base signal to be output from the BO1 pin. (BO1 data is invalid in this mode.) * Forcibly controls the charge pump output. DLC 0 (10) 1 Normal operation Forced low Charge pump output BO1 Note: If deadlock occurs due to the VCO control voltage (Vtune) going to zero and the VCO oscillator stopping, deadlock can be cleared by forcing the charge pump output to low and setting Vtune to VCC. (This is the deadlock clearing circuit.) Continued on next page. No. 5175-12/24 LC72135M Continued from preceding page. No. Control block/data IF counter control data IFS Functions * This data should be set to 1 during normal operation. * Note that if this value is set to zero the system enters input sensitivity degradation mode, and the sensitivity is reduced to 10 to 30 mV rms. * See the "IF Counter Operation" item for details. * LSI test data TEST0 TEST1 These values must all be set to 0. TEST2 These test data are set to 0 automatically after the power-on reset. (13) DNC Don't care. This data must be set to 0. Related data (11) (12) LSI test data TEST 0 to 2 3. DO Output Data (Serial Data Output) * OUT Mode 4. DO Output Data No. Control block/data I/O port data I2, I1 (1) Functions * Latched from the pin states of the LCTR/I1 input port (L/I1 bit is set to 0) and the IO2 I/O port. These values follow the pin states regardless of the input or output setting. Data is latched when the data output mode is entered. High: 1 I1 LCTR/I1 pin state I2 IO2 pin state Low: 0 * Latched from the state of the unlock detection circuit. UL 0: Unlocked UL 1: Locked or detection stopped mode * Latched from the value of the IF counter (20-bit binary counter). C19 MSB of the binary counter C0 LSB of the binary counter Related data L/I1 IOC2 (2) PLL unlock data UL IF counter binary data C19 to C0 UL0, UL1 CTE, GT0, GT1 (3) No. 5175-13/24 LC72135M 5. Serial Data Input (IN1/IN2) tSU, tHD, tEL, tES, tEH 0.75 s, tLC 0.75 s 6. Serial Data Output (OUT) tSU, tHD, tEL, tES, tEH 0.75 s, tDC, tDH 0.35 s* No. 5175-14/24 LC72135M 7. Serial Data Timing Parameter Data setup time Data hold time Clock low-level time Clock high-level time CE wait time CE setup time CE hold time Data latch change time Symbol tSU tHD tCL tCH tEL tES tEH tLC tDC DO, CL DO, CE DI, CL DI, CL CL CL CE, CL CE, CL CE, CL Pins Conditions min 0.75 0.75 0.75 0.75 0.75 0.75 0.75 typ max Unit s s s s s s s 0.75 Differs depending on the value of the pull-up resistor and the printed circuit board capacitances. s Data output time tDH 0.35 s No. 5175-15/24 LC72135M Programmable Divider Structure DVS A B C 1 0 0 SNS * 1 0 Input pin FMIN AMIN AMIN Set divisor 272 to 65535 272 to 65535 4 to 4095 Actual divisor: N Twice the set value The set value The set value Input frequency range (MHz) 10 to 160 2 to 40 0.5 to 10 Note: * Don't care. 1. Programmable Divider Calculation Examples * FM, 50 kHz steps (DVS = 1, SNS = *, FMIN selected) FM RF = 90.0 MHz (IF = +10.7 MHz) FM VCO = 100.7 MHz PLL fref = 25 kHz (R0 to R1 = 1, R2 to R3 = 0) 100.7 MHz (FM VCO) / 25 kHz (fref) / 2 (FMIN: divide-by-two prescaler) = 2014 07DE (HEX) * SW, 5 kHz steps (DVS = 0, SNS = 1, AMIN high-speed side selected) SW RF = 21.75 MHz (IF = +450 kHz) SW VCO = 22.20 MHz PLL fref = 5 kHz (R0 = R2 = 0, R1 = R3 = 1) 22.2 MHz (SW VCO) / 5 kHz (fref) = 4440 1158 (HEX) * MW, 10 kHz steps (DVS = 0, SNS = 0, AMIN low-speed side selected) MW RF = 1000 kHz (IF = +450 kHz) MW VCO = 1450 kHz PLL fref = 10 kHz (R0 to R2 = 0, R3 = 1) 1450 kHz (MW VCO) / 10 kHz (fref) = 145 091 (HEX) No. 5175-16/24 LC72135M IF Counter Structure The LC72135M IF counter is a 20-bit binary counter that accepts an IF input from either the HCTR pin (for FM or AM IF counting) or the LCTR/I1 pin (for AM IF counting). The result of the count can be read out serially through the DO pin starting with the MSB. GT1 0 0 1 1 GT0 0 1 0 1 Measurement time Measurement period (GT) (ms) 4 8 32 64 Wait time (tWU) (ms) 3 to 4 3 to 4 7 to 8 7 to 8 The IF frequency (Fc) is measured by determining how many pulses were input to an IF counter in a specified measurement period, GT. Fc = C GT (C = Fc x GT) C: Count value (number of pulses) 1. IF Counter Frequency Calculation Examples * When the measurement period (GT) is 32 ms, the count (C) is 53980 hexadecimal (342400 decimal): IF frequency (Fc) = 342400 / 32 ms = 10.7 MHz * When the measurement period (GT) is 8 ms, the count (C) is E10 hexadecimal (3600 decimal): IF frequency (Fc) = 3600 / 8 ms = 450 kHz No. 5175-17/24 LC72135M 2. IF Counter Operation Before starting the IF count, the IF counter must be reset in advance by setting CTE in the serial data to 0. The IF count is started by changing the CTE bit in the serial data from 0 to 1. The serial data is latched by the LC72135M when the CE pin is dropped from high to low. The IF signal must be supplied to the HCTR and LCTR pins in the period between the point the CE pin goes low and the end of the wait time at the latest. Next, the value of the IF counter at the end of the measurement period must be read out during the period that CTE is 1. This is because the IF counter is reset when CTE is set to 0. Note: When operating the IF counter, the control microprocessor must first check the state of the IF-IC SD (station detect) signal and only after determining that the SD signal is present turn on IF buffer output and execute an IF count operation. Autosearch techniques that use only the IF counter are not recommended, since it is possible for IF buffer leakage output to cause incorrect stops at points where there is no station. Note that the LC72135M 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 an IF-IC that does not provide an SD output and auto-search is implemented using only IF counting. HCTR minimum input sensitivity standard f (MHz) IFS 1: Normal mode 0: Degradation mode 0.4 f < 0.5 40 mVrms (0.1 to 3 mVrms) 70 mVrms (10 to 15 mVrms) 0.5 f < 8 40 mVrms 70 mVrms 8 f 12 40 mVrms (1 to 10 mVrms) 70 mVrms (30 to 40 mVrms) Note: Values in parentheses are actual performance values presented as reference data. No. 5175-18/24 LC72135M Unlock Detection Timing 1. Unlock Detection Determination Timing Unlocked state detection is performed in the reference frequency (fref) period (interval). Therefore, in principle, unlock determination requires a time longer than the period of the reference frequency. However, immediately after changing the divisor N (frequency) unlock detection must be performed after waiting at least two periods of the reference frequency. Figure 1 Unlocked State Detection Timing For example, if fref is 1 kHz, i.e., the period is 1 ms, after changing the divisor N, the system must wait at least 2 ms before checking for the unlocked state. Figure 2 Circuit Structure No. 5175-19/24 LC72135M 2. Unlock Detection Software Figure 3 3. Unlocked State Data Output Using Serial Data Output In the LC72135M, once an unlocked state occurs, the unlocked state serial data (UL) will not be reset until a data input (or output) operation is performed. At the data output x point in Figure 3, although the VCO frequency has stabilized (locked), since no data output has been performed since the divisor N was changed the unlocked state data remains in the unlocked state. As a result, even though the frequency has stabilized (locked), the system remains (from the standpoint of the data) in the unlocked state. Therefore, the unlocked state data acquired at data output x, which occurs immediately after the divisor N was changed, should be treated as a dummy data output and ignored. The second data output (data output ) and following outputs are valid data. Locked State Determination Flowchart 4. Directly Outputting Unlocked State Data from the DO Pin (Set by the DO pin control data) Since the locking state (high = locked, low = unlocked) is output directly from the DO pin, the dummy data processing described in section 3 above is not required. After changing the divisor N, the locking state can be checked after waiting at least two reference frequency periods. No. 5175-20/24 LC72135M Clock Time Base Usage Notes The pull-up resistor used on the clock time base output pin (BO1) should be at least 100 k. This is to prevent degrading the VCO C/N characteristics when a loop filter is formed using the built-in low-pass filter transistor. Since the clock time base output pin and the low-pass filter have a common ground internal to the IC, it is necessary to minimize the time base output pin current fluctuations and to suppress their influence on the low-pass filter. Also, to prevent chattering we recommend using a Schmitt input at the controller (microprocessor) that receives this signal. Other Items DZ1 0 0 1 1 DZ0 0 1 0 1 Dead zone mode DZA DZB DZC DZD Charge pump ON/ON ON/ON OFF/OFF OFF/OFF Dead zone - -0 s -0 s +0 s + +0 s 1. Notes on the Phase Comparator Dead Zone Since correction pulses are output from the charge pump even if the PLL is locked when the charge pump is in the ON/ON state, the loop can easily become unstable. This point requires special care when designing application circuits. The following problems may occur in the ON/ON state. * Side band generation due to reference frequency leakage * Side band generation due to both the correction pulse envelope and low frequency leakage Schemes in which a dead zone is present (OFF/OFF) have good loop stability, but have the problem that acquiring a high C/N ratio can be difficult. On the other hand, although it is easy to acquire a high C/N ratio with schemes in which there is no dead zone, it is difficult to achieve high loop stability. Therefore, it can be effective to select DZA or DZB, which have no dead zone, in applications which require an FM S/R ratio in excess of 90 to 100 dB, or in which an increased AM stereo pilot margin is desired. On the other hand, we recommend selecting DZC or DZD, which provide a dead zone, for applications which do not require such a high FM signal-to-noise ratio and in which either AM stereo is not used or an adequate AM stereo pilot margin can be achieved. No. 5175-21/24 LC72135M Dead Zone The phase comparator compares fp to a reference frequency (fr) as shown in Figure 4. Although the characteristics of this circuit (see Figure 5) are such that the output voltage is proportional to the phase difference o (line A), a region (the dead zone) in which it is not possible to compare small phase differences occurs in actual ICs due to internal circuit delays and other factors (line B). A dead zone as small as possible is desirable for products that must provide a high S/N ratio. However, since a larger dead zone makes this circuit easier to use, a larger dead zone is appropriate for popularlypriced products. This is because it is possible for RF signals to leak from the mixer to the VCO and modulate the VCO in popularly-priced products in the presence of strong RF inputs. When the dead zone is narrow, the circuit outputs correction pulses and this output can further modulate the VCO and generate beat frequencies with the RF signal. Figure 4 Figure 5 2. Notes on the FMIN, AMIN, HCTR and LCTR/I1 Pins Coupling capacitors must be placed as close as possible to their respective pins. A capacitance of about 100 pF is desirable. In particular, if a capacitance of 1000 pF or over is used for the HCTR and LCTR/I1 pins, the time to reach the bias level will increase and incorrect counting may occur due to the relationship with the wait time. 3. Notes on IF Counting SD must be used in conjunction with the IF counting time When using IF counting, always implement IF counting by having the microprocessor determine the presence of the IF-IC SD (station detect) signal and turn on the IF counter buffer only if the SD signal is present. Schemes in which auto-searches are performed with only IF counting are not recommended, since they can stop at points where there is no signal due to leakage output from the IF counter buffer. 4. DO Pin Usage Techniques In addition to data output mode times, the DO pin can also be used to check for IF counter count completion and for unlock detection output. Also, an input pin state can be output unchanged through the DO pin and input to the controller. 5. Power Supply Pins A capacitor of at least 2000 pF must be inserted between the power supply VDD and VSS pins for noise exclusion. This capacitor must be placed as close as possible to the VDD and VSS pins. 6. VCO Setup Applications must be designed so that the VCO (local oscillator) does not stop, even if the control voltage (Vtune) goes to 0 V. If it is possible for the oscillator to stop, the application must use the control data (DLC) to temporarily force Vtune to VCC to prevent deadlock from occurring. (Deadlock clear circuit) No. 5175-22/24 LC72135M Pin States after the Power ON Reset Application System Example No. 5175-23/24 LC72135M Specifications of any and all SANYO products described or contained herein stipulate the performance, characteristics, and functions of the described products in the independent state, and are not guarantees of the performance, characteristics, and functions of the described products as mounted in the customer's products or equipment. To verify symptoms and states that cannot be evaluated in an independent device, the customer should always evaluate and test devices mounted in the customer's products or equipment. SANYO Electric Co., Ltd. strives to supply high-quality high-reliability products. However, any and all semiconductor products fail with some probability. It is possible that these probabilistic failures could give rise to accidents or events that could endanger human lives, that could give rise to smoke or fire, or that could cause damage to other property. When designing equipment, adopt safety measures so that these kinds of accidents or events cannot occur. Such measures include but are not limited to protective circuits and error prevention circuits for safe design, redundant design, and structural design. In the event that any and all SANYO products described or contained herein fall under strategic products (including services) controlled under the Foreign Exchange and Foreign Trade Control Law of Japan, such products must not be exported without obtaining export license from the Ministry of International Trade and Industry in accordance with the above law. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, or any information storage or retrieval system, or otherwise, without the prior written permission of SANYO Electric Co., Ltd. Any and all information described or contained herein are subject to change without notice due to product/technology improvement, etc. When designing equipment, refer to the "Delivery Specification" for the SANYO product that you intend to use. Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed for volume production. 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 August, 1998. Specifications and information herein are subject to change without notice. PS No. 5175-24/24 |
Price & Availability of LC72135M
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