CD4046BM/CD4046BC Micropower Phase-Locked Loop

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Transcription:

CD4046BM/CD4046BC Micropower Phase-Locked Loop General Description The CD4046B micropower phase-locked loop (PLL) consists of a low power, linear, voltage-controlled oscillator (VCO), a source follower, a zener diode, and two phase comparators. The two phase comparators have a common signal input and a common comparator input. The signal input can be directly coupled for a large voltage signal, or capacitively coupled to the self-biasing amplifier at the signal input for a small voltage signal. Phase comparator I, an exclusive OR gate, provides a digital error signal (phase comp. I Out) and maintains 90 phase shifts at the VCO center frequency. Between signal input and comparator input (both at 50% duty cycle), it may lock onto the signal input frequencies that are close to harmonics of the VCO center frequency. Phase comparator II is an edge-controlled digital memory network. It provides a digital error signal (phase comp. II Out) and lock-in signal (phase pulses) to indicate a locked condition and maintains a 0 phase shift between signal input and comparator input. The linear voltage-controlled oscillator (VCO) produces an output signal (VCO Out) whose frequency is determined by the voltage at the VCO IN input, and the capacitor and resistors connected to pin C1 A,C1 B, R1 and R2. The source follower output of the VCO IN (demodulator Out) is used with an external resistor of 10 kω or more. The INHIBIT input, when high, disables the VCO and source follower to minimize standby power consumption. The zener diode is provided for power supply regulation, if necessary. Features n Wide supply voltage range: 3.0V to 18V n Low dynamic power consumption: 70 µw (typ.) at f o = 10 khz, = 5V n VCO frequency: 1.3 MHz (typ.) at = 10V n Low frequency drift: 0.06%/ C at = 10V with temperature n High VCO linearity: 1% (typ.) Applications n FM demodulator and modulator n Frequency synthesis and multiplication n Frequency discrimination n Data synchronization and conditioning n Voltage-to-frequency conversion n Tone decoding n FSK modulation n Motor speed control November 1995 CD4046BM/CD4046BC Micropower Phase-Locked Loop CD4046BM/CD4046BC 1997 National Semiconductor Corporation DS005968 www.national.com 1 PrintDate=1997/07/02 PrintTime=16:01:18 13464 ds005968 Rev. No. 1 Proof 1

Block Diagram Connection Diagram FIGURE 1. Dual-In-Line Package DS005968-1 Top View Order Number CD4046B DS005968-2 www.national.com 2 PrintDate=1997/07/02 PrintTime=16:01:18 13464 ds005968 Rev. No. 1 Proof 2

Absolute Maximum Ratings (Notes 1, 2) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. DC Supply Voltage ( ) 0.5 to +18 V DC Input Voltage (V IN ) 0.5 to +0.5 V DC Storage Temperature Range (T S ) 65 C to +150 C Power Dissipation (P D ) Dual-In-Line 700 mw Small Outline 500 mw Lead Temperature (T L ) (Soldering, 10 seconds) Recommended Operating Conditions (Note 2) DC Supply Voltage ( ) Input Voltage (V IN ) Operating Temperature Range (T A ) CD4046BM CD4046BC 260 C 3 to 15 V DC 0 to V DC 55 C to +125 C 40 C to +85 C DC Electrical Characteristics CD4046BM (Note 2) Symbol Parameter Conditions 55 C +25 C +125 C Units Min Max Min Typ Max Min Max I DD Quiescent Device Current Pin 5 =, Pin 14 =, Pin 3, 9 = V SS = 5V 5 0.005 5 150 µa = 10V 10 0.01 10 300 µa = 15V 20 0.015 20 600 µa Pin 5 =, Pin 14 = Open, Pin 3, 2 = V SS = 5V 45 5 35 185 µa = 10V 450 20 350 650 µa = 15V 1200 50 900 1500 µa V OL Low Level Output Voltage = 5V 0.05 0 0.05 0.05 V = 10V 0.05 0 0.05 0.05 V = 15V 0.05 0 0.05 0.05 V V OH High Level Output Voltage = 5V 4.95 4.95 5 4.95 V = 10V 9.95 9.95 10 9.95 V = 15V 14.95 14.95 15 14.95 V V IL Low Level Input Voltage = 5V, V O = 0.5V or 4.5V 1.5 2.25 1.5 1.5 V Comparator and Signal In = 10V, V O = 1V or 9V 3.0 4.5 3.0 3.0 V = 15V, V O = 1.5V or 13.5V 4.0 6.25 4.0 4.0 V V IH High Level Input Voltage = 5V, V O = 0.5V or 4.5V 3.5 3.5 2.75 3.5 V Comparator and Signal In = 10V, V O = 1V or 9V 7.0 7.0 5.5 7.0 V = 15V, V O = 1.5V or 13.5V 11.0 11.0 8.25 11.0 V I OL Low Level Output Current = 5V, V O = 0.4V 0.64 0.51 0.88 0.36 ma (Note 4) = 10V, V O = 0.5V 1.6 1.3 2.25 0.9 ma = 15V, V O = 1.5V 4.2 3.4 8.8 2.4 ma I OH High Level Output Current = 5V, V O = 4.6V 0.64 0.51 0.88 0.36 ma (Note 4) = 10V, V O = 9.5V 1.6 1.3 2.25 0.9 ma = 15V, V O = 13.5V 4.2 3.4 8.8 2.4 ma I IN Input Current All Inputs Except Signal Input = 14V, V IN = 0V 0.1 10 5 0.1 1.0 µa = 15V, V IN = 15V 0.1 10 5 0.1 1.0 µa C IN Input Capacitance Any Input (Note 3) 7.5 pf 3 www.national.com PrintDate=1997/07/02 PrintTime=16:01:21 13464 ds005968 Rev. No. 1 Proof 3

DC Electrical Characteristics (Continued) CD4046BM (Note 2) Symbol Parameter Conditions 55 C +25 C +125 C Units Min Max Min Typ Max Min Max P T Total Power Dissipation f o = 10 khz, R1 = 1MΩ R2 =, VCO IN = /2 = 5V 0.07 mw = 10V 0.6 mw = 15V 2.4 mw DC Electrical Characteristics CD4046BC (Note 2) Symbol Parameter Conditions 40 C +25 C +85 C Units Min Max Min Typ Max Min Max I DD Quiescent Device Current Pin 5 =, Pin 14 =, Pin 3, 9 = V SS = 5V 20 0.005 20 150 µa = 10V 40 0.01 40 300 µa = 15V 80 0.015 80 600 µa Pin 5 =, Pin 14 = Open, Pin 3, 9 = V SS = 5V 70 5 55 205 µa = 10V 530 20 410 710 µa = 15V 1500 50 1200 1800 µa V OL Low Level Output Voltage = 5V 0.05 0 0.05 0.05 V = 10V 0.05 0 0.05 0.05 V = 15V 0.05 0 0.05 0.05 V V OH High Level Output Voltage = 5V 4.95 4.95 5 4.95 V = 10V 9.95 9.95 10 9.95 V = 15V 14.95 14.95 15 14.95 V V IL Low Level Input Voltage = 5V, V O = 0.5V or 4.5V 1.5 2.25 1.5 1.5 V Comparator and Signal In = 10V, V O = 1V or 9V 3.0 4.5 3.0 3.0 V = 15V, V O = 1.5V or 13.5V 4.0 6.25 4.0 4.0 V V IH High Level Input Voltage = 5V, V O = 0.5V or 4.5V 3.5 3.5 2.75 3.5 V Comparator and Signal In = 10V, V O = 1V or 9V 7.0 7.0 5.5 7.0 V = 15V, V O = 1.5V or 13.5V 11.0 11.0 8.25 11.0 V I OL Low Level Output Current = 5V, V O = 0.4V 0.52 0.44 0.88 0.36 ma (Note 4) = 10V, V O = 0.5V 1.3 1.1 2.25 0.9 ma = 15V, V O = 1.5V 3.6 3.0 8.8 2.4 ma I OH High Level Output Current = 5V, V O = 4.6V 0.52 0.44 0.88 0.36 ma (Note 4) = 10V, V O = 9.5V 1.3 1.1 2.25 0.9 ma = 15V, V O = 13.5V 3.6 3.0 8.8 2.4 ma I IN Input Current All Inputs Except Signal Input = 15V, V IN = 0V 0.3 10 5 0.3 1.0 µa = 15V, V IN = 15V 0.3 10 5 0.3 1.0 µa C IN Input Capacitance Any Input (Note 3) 7.5 pf www.national.com 4 PrintDate=1997/07/02 PrintTime=16:01:27 13464 ds005968 Rev. No. 1 Proof 4

DC Electrical Characteristics (Continued) CD4046BC (Note 2) Symbol Parameter Conditions 40 C +25 C +85 C Units Min Max Min Typ Max Min Max P T Total Power Dissipation f o = 10 khz, R1 = 1MΩ, R2 =, VCO IN = /2 = 5V 0.07 mw = 10V 0.6 mw = 15V 2.4 mw Note 1: Absolute Maximum Ratings are those values beyond which the safety of the device cannot be guaranteed. They are not meant to imply that the devices should be operated at these limits. The table of Recommended Operating Conditions and Electrical Characteristics provides conditions for actual device operation. Note 2: V SS = 0V unless otherwise specified. Note 3: Capacitance is guaranteed by periodic testing. Note 4: I OH and I OL are tested one output at a time. AC Electrical Characteristics CD4046BM/CD4046BC T A = 25 C, C L = 50 pf (Note 5) Symbol Parameter Conditions Min Typ Max Units VCO SECTION I DD Operating Current f o = 10 khz, R1 = 1MΩ, R2 =, VCO IN = /2 = 5V 20 µa = 10V 90 µa = 15V 200 µa f MAX Maximum Operating Frequency C1 = 50 pf, R1 = 10 kω, R2 =, VCO IN = = 5V 0.4 0.8 MHz = 10V 0.6 1.2 MHz = 15V 1.0 1.6 MHz Linearity VCO IN = 2.5V ±0.3V, R1 10 kω, = 5V 1 % VCO IN = 5V ±2.5V, R1 400 kω, = 10V 1 % VCO IN = 7.5V ±5V, R1 1MΩ, = 15V 1 % Temperature-Frequency Stability %/ C<5c1/f. No Frequency Offset, f MIN = 0 R2 = = 5V 0.12 0.24 %/ C = 10V 0.04 0.08 %/ C = 15V 0.015 0.03 %/ C Frequency Offset, f MIN 0 = 5V 0.06 0.12 %/ C = 10V 0.05 0.1 %/ C = 15V 0.03 0.06 %/ C VCO IN Input Resistance = 5V 10 6 MΩ = 10V 10 6 MΩ = 15V 10 6 MΩ VCO Output Duty Cycle = 5V 50 % = 10V 50 % = 15V 50 % 5 www.national.com PrintDate=1997/07/02 PrintTime=16:01:29 13464 ds005968 Rev. No. 1 Proof 5

AC Electrical Characteristics (Continued) CD4046BM/CD4046BC T A = 25 C, C L = 50 pf (Note 5) Symbol Parameter Conditions Min Typ Max Units VCO SECTION t THL VCO Output Transition Time = 5V 90 200 ns t THL = 10V 50 100 ns = 15V 45 80 ns PHASE COMPARATORS SECTION R IN Input Resistance Signal Input = 5V 1 3 MΩ = 10V 0.2 0.7 MΩ = 15V 0.1 0.3 MΩ Comparator Input = 5V 10 6 MΩ = 10V 10 6 MΩ = 15V 10 6 MΩ AC-Coupled Signal Input Voltage C SERIES = 1000 pf Sensitivity f = 50 khz = 5V 200 400 mv = 10V 400 800 mv = 15V 700 1400 mv DEMODULATOR OUTPUT VCO IN Offset Voltage RS 10 kω, = 5V 1.50 2.2 V V DEM RS 10 kω, = 10V 1.50 2.2 V RS 50 kω, = 15V 1.50 2.2 V Linearity RS 50 kω VCO IN = 2.5V ±0.3V, 0.1 % = 5V VCO IN = 5V ±2.5V, = 0.6 % 10V VCO IN = 7.5V ±5V, = 15V 0.8 % ZENER DIODE V Z Zener Diode Voltage I Z = 50 µa 6.3 7.0 7.7 V R Z Zener Dynamic Resistance I Z = 1 ma 100 Ω Note 5: AC Parameters are guaranteed by DC correlated testing. www.national.com 6 PrintDate=1997/07/02 PrintTime=16:01:31 13464 ds005968 Rev. No. 1 Proof 6

Phase Comparator State Diagrams Typical Waveforms FIGURE 2. DS005968-3 FIGURE 3. Typical Waveform Employing Phase Comparator I in Locked Condition DS005968-4 FIGURE 4. Typical Waveform Employing Phase Comparator II in Locked Condition DS005968-5 7 www.national.com PrintDate=1997/07/02 PrintTime=16:01:31 13464 ds005968 Rev. No. 1 Proof 7

Typical Performance Characteristics Typical Center Frequency vs C1 for R1 = 10 kω, 100 kω and1mω FIGURE 5. DS005968-6 Typical Frequency vs C1 for R2 = 10 kω, 100 kω and1mω FIGURE 6. DS005968-13 Note: To obtain approximate total power dissipation of PLL system for no-signal input: Phase Comparator I, P D (Total) = P D (f o )+P D (f MIN )+P D (R S ); Phase Comparator II, P D (Total) = P D (f MIN ). www.national.com 8 PrintDate=1997/07/02 PrintTime=16:01:32 13464 ds005968 Rev. No. 1 Proof 8

Typical Performance Characteristics (Continued) Typical f MAX /f MIN vs R2/R1 FIGURE 7. DS005968-14 Typical VCO Power Dissipation at Center Frequency vs R1 FIGURE 8. DS005968-15 Note: To obtain approximate total power dissipation of PLL system for no-signal input: Phase Comparator I, P D (Total) = P D (f o )+P D (f MIN )+P D (R S ); Phase Comparator II, P D (Total) = P D (f MIN ). 9 www.national.com PrintDate=1997/07/02 PrintTime=16:01:32 13464 ds005968 Rev. No. 1 Proof 9

Typical Performance Characteristics (Continued) Typical VCO Power Dissipation at f MIN vs R2 FIGURE 9. DS005968-16 Typical Source Follower Power Dissipation vs R S FIGURE 10. DS005968-17 Note: To obtain approximate total power dissipation of PLL system for no-signal input: Phase Comparator I, P D (Total) = P D (f o )+P D (f MIN )+P D (R S ); Phase Comparator II, P D (Total) = P D (f MIN ). www.national.com 10 PrintDate=1997/07/02 PrintTime=16:01:33 13464 ds005968 Rev. No. 1 Proof 10

Typical Performance Characteristics (Continued) DS005968-18 Note: To obtain approximate total power dissipation of PLL system for no-signal input: Phase Comparator I, P D (Total) = P D (f o )+P D (f MIN )+P D (R S ); Phase Comparator II, P D (Total) = P D (f MIN ). Design Information This information is a guide for approximating the value of external components for the CD4046B in a phase-locked-loop system. The selected external components must be within the following ranges: R1, R2 10 kω, R S 10 kω, C1 50 pf. FIGURE 11. Typical VCO Linearity vs R1 and C1 DS005968-19 In addition to the given design information, refer to Figure 5, Figure 6, Figure 7 for R1, R2 and C1 component selections. 11 www.national.com PrintDate=1997/07/02 PrintTime=16:01:33 13464 ds005968 Rev. No. 1 Proof 11

Design Information (Continued) Using Phase Comparator I Using Phase Comparator II Characteristics VCO Without Offset VCO With Offset VCO Without Offset VCO With Offset R2 = R2 = VCO Frequency For No Signal Input VCO in PLL system will adjust VCO in PLL system will adjust to Frequency Lock Range, 2 f L Frequency Capture Range, 2 f C to center frequency, f o lowest operating frequency, f min 2 f L = full VCO frequency range 2f L =f max f min Loop Filter Component Selection For2f C, see Ref. f C = f L Phase Angle Between 90 at center frequency (f o ), approximating Always 0 in lock Single and Comparator 0 and 180 at ends of lock range (2 f L ) Locks on Harmonics Yes No of Center Frequency Signal Input Noise High Low Rejection VCO Component Given: f o. Given: f o and f L. Given: f max. Given: f min and f max. Selection Use f o with Calculate f min Calculate f o from Use f min with Figure 5 to from the equation the equation Figure 6 to determine R1 and C1. f min = f o f L. to determine R2 and C1. Use f min with Figure 6 to determine R2 and C1. Calculate Use f o with Figure 5 to Calculate determine R1 and C1. Use from the equation with Figure 7 to determine ratio R2/R1 to obtain R1. Use with Figure 7 to determine ratio R2/ R1 to obtain R1. www.national.com 12 PrintDate=1997/07/02 PrintTime=16:01:34 13464 ds005968 Rev. No. 1 Proof 12

References G.S. Moschytz, Miniaturized RC Filters Using Phase-Locked Loop, BSTJ, May, 1965. Floyd Gardner, Phaselock Techniques, John Wiley & Sons, 1966. Book Extract End 13 www.national.com PrintDate=1997/07/02 PrintTime=16:01:34 13464 ds005968 Rev. No. 1 Proof 13

THIS PAGE IS IGNORED IN THE DATABOOK 14 PrintDate=1997/07/02 PrintTime=16:01:34 13464 ds005968 Rev. No. 1 Proof 14

Physical Dimensions inches (millimeters) unless otherwise noted Order Number CD4046BMJ or CD4046BCJ NS Package Number J16A Order Number CD4046BMN or CD4046BCN NS Package Number N16E 15 www.national.com 15 PrintDate=1997/07/02 PrintTime=16:01:35 13464 ds005968 Rev. No. 1 Proof 15

CD4046BM/CD4046BC Micropower Phase-Locked Loop LIFE SUPPORT POLICY NATIONAL S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DE- VICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL SEMI- CONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. 2. A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. National Semiconductor Corporation Americas Tel: 1-800-272-9959 Fax: 1-800-737-7018 Email: support@nsc.com www.national.com National Semiconductor Europe Fax: +49 (0) 1 80-530 85 86 Email: europe.support@nsc.com Deutsch Tel: +49 (0) 1 80-530 85 85 English Tel: +49 (0) 1 80-532 78 32 Français Tel: +49 (0) 1 80-532 93 58 Italiano Tel: +49 (0) 1 80-534 16 80 National Semiconductor Hong Kong Ltd. 13th Floor, Straight Block, Ocean Centre, 5 Canton Rd. Tsimshatsui, Kowloon Hong Kong Tel: (852) 2737-1600 Fax: (852) 2736-9960 National Semiconductor Japan Ltd. Tel: 81-3-5620-6175 Fax: 81-3-5620-6179 National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. PrintDate=1997/07/02 PrintTime=16:01:35 13464 ds005968 Rev. No. 1 Proof 16