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MSI
Phase-locked loop
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INTEGRATED CIRCUITS
DATA SHEET
For a complete data sheet, please also download:
· The IC04 LOCMOS HE4000B Logic Family Specifications HEF, HEC · The IC04 LOCMOS HE4000B Logic Package Outlines/Information HEF, HEC
HEF4046B MSI Phase-locked loop
Product specification File under Integrated Circuits, IC04 January 1995
Philips Semiconductors
Product specification
Phase-locked loop
DESCRIPTION The HEF4046B is a phase-locked loop circuit that consists of a linear voltage controlled oscillator (VCO) and two different phase comparators with a common signal input amplifier and a common comparator input. A 7 V regulator (zener) diode is provided for supply voltage regulation if necessary. For functional description see further on in this data.
HEF4046B MSI
Fig.1 Functional diagram.
FAMILY DATA HEF4046BP(N): HEF4046BD(F): HEF4046BT(D): 16-lead DIL; plastic (SOT38-1) 16-lead DIL; ceramic (cerdip) (SOT74) 16-lead SO; plastic (SOT109-1) ( ): Package Designator North America IDD LIMITS category MSI See further on in this data. See Family Specifications
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Philips Semiconductors
Product specification
Phase-locked loop
PINNING 1. Phase comparator pulse output 2. Phase comparator 1 output 3. Comparator input 4. VCO output 5. Inhibit input 6. Capacitor C1 connection A 7. Capacitor C1 connection B 8. VSS 9. VCO input 10. Source-follower output 11. Resistor R1 connection 12. Resistor R2 connection 13. Phase comparator 2 output 14. Signal input
HEF4046B MSI
15. Zener diode input for regulated supply. Fig.2 Pinning diagram.
FUNCTIONAL DESCRIPTION VCO part The VCO requires one external capacitor (C1) and one or two external resistors (R1 or R1 and R2). Resistor R1 and capacitor C1 determine the frequency range of the VCO. Resistor R2 enables the VCO to have a frequency off-set if required. The high input impedance of the VCO simplifies the design of low-pass filters; it permits the designer a wide choice of resistor/capacitor ranges. In order not to load the low-pass filter, a source-follower output of the VCO input voltage is provided at pin 10. If this pin (SFOUT) is used, a load resistor (RSF) should be connected from this pin to VSS; if unused, this pin should be left open. The VCO output (pin 4) can either be connected directly to the comparator input (pin 3) or via a frequency divider. A LOW level at the inhibit input (pin 5) enables the VCO and the source follower, while a HIGH level turns off both to minimize stand-by power consumption. Phase comparators The phase-comparator signal input (pin 14) can be direct-coupled, provided the signal swing is between the standard HE4000B family input logic levels. The signal must be capacitively coupled to the self-biasing amplifier at the signal input in case of smaller swings. Phase comparator 1 is an EXCLUSIVE-OR network. The signal and comparator input frequencies must have a 50% duty January 1995 3
factor to obtain the maximum lock range. The average output voltage of the phase comparator is equal to 1/2 VDD when there is no signal or noise at the signal input. The average voltage to the VCO input is supplied by the low-pass filter connected to the output of phase comparator 1. This also causes the VCO to oscillate at the centre frequency (fo). The frequency capture range (2 fc) is defined as the frequency range of input signals on which the PLL will lock if it was initially out of lock. The frequency lock range (2 fL) is defined as the frequency range of input signals on which the loop will stay locked if it was initially in lock. The capture range is smaller or equal to the lock range. With phase comparator 1, the range of frequencies over which the PLL can acquire lock (capture range) depends on the low-pass filter characteristics and this range can be made as large as the lock range. Phase comparator 1 enables the PLL system to remain in lock in spite of high amounts of noise in the input signal. A typical behaviour of this type of phase comparator is that it may lock onto input frequencies that are close to harmonics of the VCO centre frequency. Another typical behaviour is, that the phase angle between the signal and comparator input varies between 0° and 180° and is 90° at the centre frequency. Figure 3 shows the typical phase-to-output response characteristic.
Philips Semiconductors
Product specification
Phase-locked loop
HEF4046B MSI
(1) Average output voltage.
Fig.3
Signal-to-comparator inputs phase difference for comparator 1.
Figure 4 shows the typical waveforms for a PLL employing phase comparator 1 in locked condition of fo.
Fig.4 Typical waveforms for phase-locked loop employing phase comparator 1 in locked condition of fo.
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Philips Semiconductors
Product specification
Phase-locked loop
Phase comparator 2 is an edge-controlled digital memory network. It consists of four flip-flops, control gating and a 3-state output circuit comprising p and n-type drivers having a common output node. When the p-type or n-type drivers are ON, they pull the output up to VDD or down to VSS respectively. This type of phase comparator only acts on the positive-going edges of the signals at SIGNIN and COMPIN. Therefore, the duty factors of these signals are not of importance. If the signal input frequency is higher than the comparator input frequency, the p-type output driver is maintained ON most of the time, and both the n and p-type drivers are OFF (3-state) the remainder of the time. If the signal input frequency is lower than the comparator input frequency, the n-type output driver is maintained ON most of the time, and both the n and p-type drivers are OFF the remainder of the time. If the signal input and comparator input frequencies are equal, but the signal input lags the comparator input in phase, the n-type output driver is maintained ON for a time corresponding to the phase difference. If the comparator input lags the signal input in phase, the p-type output driver is maintained ON for a time corresponding to the phase difference. Subsequently, the voltage at the capacitor of the low-pass filter connected to this phase comparator is adjusted until the signal and
HEF4046B MSI
comparator inputs are equal in both phase and frequency. At this stable point, both p and n-type drivers remain OFF and thus the phase comparator output becomes an open circuit and keeps the voltage at the capacitor of the low-pass filter constant. Moreover, the signal at the phase comparator pulse output (PCPOUT) is a HIGH level which can be used for indicating a locked condition. Thus, for phase comparator 2 no phase difference exists between the signal and comparator inputs over the full VCO frequency range. Moreover, the power dissipation due to the low-pass filter is reduced when this type of phase comparator is used because both p and n-type output drivers are OFF for most of the signal input cycle. It should be noted that the PLL lock range for this type of phase comparator is equal to the capture range, independent of the low-pass filter. With no signal present at the signal input, the VCO is adjusted to its lowest frequency for phase comparator 2 . Figure 5 shows typical waveforms for a PLL employing this type of phase comparator in locked condition.
Fig.5 Typical waveforms for phase-locked loop employing phase comparator 2 in locked condition.
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Philips Semiconductors
Product specification
Phase-locked loop
Figure 6 shows the state diagram for phase comparator 2. Each circle represents a state of the comparator. The number at the top, inside each circle, represents the state of the comparator, while the logic state of the signal and comparator inputs are represented by a `0' for a logic LOW or a `1' for a logic HIGH, and they are shown in the left and right bottom of each circle. The transitions from one to another result from either a logic change at the signal input (S) or the comparator input (C). A positive-going and a negative-going transition are shown by an arrow pointing up or down respectively.
HEF4046B MSI
The state diagram assumes, that only one transition on either the signal input or comparator input occurs at any instant. States 3, 5, 9 and 11 represent the condition at the output when the p-type driver is ON, while states 2, 4, 10 and 12 determine the condition when the n-type driver is ON. States 1, 6, 7 and 8 represent the condition when the output is in its high impedance OFF state; i.e. both p and n-type drivers are OFF, and the PCPOUT output is HIGH. The condition at output PCPOUT for all other states is LOW.
S : 0 to 1 transition at the signal input. C : 1 to 0 transition at the comparator input.
Fig.6 State diagram for comparator 2.
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Philips Semiconductors
Product specification
Phase-locked loop
DC CHARACTERISTICS VSS = 0 V Tamb (°C) VDD V Supply current (note 1) Quiescent device current (note 2) 5 10 15 5 10 15 Notes 1. Pin 15 open; pin 5 at VDD; pins 3 and 9 at VSS; pin 14 open. 2. Pin 15 open; pin 5 at VDD; pins 3 and 9 at VSS; pin 14 at VDD; input current pin 14 not included. AC CHARACTERISTICS VSS = 0 V; Tamb = 25 °C; CL = 50 pF; input transition times 20 ns VDD V Phase comparators Operating supply voltage Input resistance at SIGNIN A.C. coupled input sensitivity at SIGNIN D.C. coupled input sensitivity at SIGNIN; COMPIN LOW level 5 10 VIL 15 5 HIGH level Input current at SIGNIN 10 VIH 15 5 10 + IIN 15 5 10 -IIN 15 January 1995 7 3,5 7,0 11,0 7 30 70 3 18 45 1,5 3,0 4,0 V V V V V V µA µA µA µA µA µA 5 10 RIN 15 5 10 VIN 15 VDD 3 750 220 140 150 150 200 15 V k k k mV mV mV SYMBOL MIN. TYP. MAX. IDD ID SYMBOL - - - - - - -40 TYP. MAX. - - - 20 40 80 + 25 TYP. 20 300 750 - - - MAX. - - - 20 40 80 - - - - - -
HEF4046B MSI
+ 85 TYP. MAX. - - - 150 300 600 µA µA µA µA µA µA
at self-bias operating point peak-to-peak values; R1 = 10 k; R2 = ; C1 = 100 pF; independent of the lock range
full temperature range
SIGNIN at VDD
SIGNIN at VSS
Philips Semiconductors
Product specification
Phase-locked loop
HEF4046B MSI
VDD V SYMBOL MIN. TYP. MAX.
VCO Operating supply voltage Power dissipation 5 10 P 15 Maximum operating frequency Temperature/ frequency stability 5 10 fmax 15 5 10 15 5 10 15 Linearity 5 10 15 Duty factor at VCOOUT Input resistance at VCOIN Source follower Offset voltage VCOIN minus SFOUT 5 10 15 5 10 15 Linearity 5 10 15 Zener diode Zener voltage Dynamic resistance Notes 1. Over the recommended component range. January 1995 8 VZ RZ 7,3 25 V IZ = 50 µA IZ = 1 mA 1,7 2,0 2,1 1,5 1,7 1,8 0,3 1,0 1,3 V V V V V V % % % RSF > 50 k; see Fig.13 RSF = 50 k; VCOIN at 1/2 VDD RSF = 10 k; VCOIN at 1/2 VDD 5 10 15 5 10 RIN 15 0,5 1,0 1,3 VDD 3 5 150 2500 9000 1,0 2,0 2,7 0,220,30 0,040,05 0,010,05 00,22 00,04 00,01 0,50 0,25 0,25 50 50 50 106 106 106 15 15 V V µW µW µW MHz MHz MHz %/°C %/°C %/°C %/°C %/°C %/°C % % % % % % M M M as fixed oscillator only phase-locked loop operation fo = 10 kHz; R1 = 1 M; R2 = ; VCOIN at 1/2 VDD; see also Figs 10 and 11 VCOIN at VDD; R1 = 10 k; R2 = ; C1 = 50 pF no frequency offset (fmin = 0); see also note 1 with frequency offset (fmin > 0); see also note 1 R1 > 10 k R1 > 400 k R1 = 1 M see Fig.13 and Figs 14 15 and 16
Philips Semiconductors
Product specification
Phase-locked loop
DESIGN INFORMATION CHARACTERISTIC No signal on SIGNIN Phase angle between SIGNIN and COMPIN Locks on harmonics of centre frequency Signal input noise rejection Lock frequency range (2 fL) Capture frequency range (2 fC) USING PHASE COMPARATOR 1 VCO in PLL system adjusts to centre frequency (fo) 90° at centre frequency (fo), approaching 0° and 180° at ends of lock range (2 fL) yes high
HEF4046B MSI
USING PHASE COMPARATOR 2 VCO in PLL system adjusts to min. frequency (fmin) always 0° in lock (positive-going edges) no low
the frequency range of the input signal on which the loop will stay locked if it was initially in lock; 2 fL = full VCO frequency range = fmax - fmin the frequency range of the input signal on which the loop will lock if it was initially out of lock depends on low-pass filter characteristics; fC < fL fC = fL
Centre frequency (fo) VCO component selection
the frequency of the VCO when VCOIN at 1/2VDD
Recommended range for R1 and R2: 10 k to 1 M; for C1: 50 pF to any practical value. 1. VCO without frequency offset (R2 = ). a) Given fo: use fo with Fig.7 to determine R1 and C1. b) Given fmax: calculate fo from fo = 1/2 fmax; use fo with Fig.7 to determine R1 and C1. 2. VCO with frequency offset. a) Given fo and fL : calculate fmin from the equation fmin = fo - fL; use fmin with Fig.8 to determine R2 and C1; calculate f max f max fo + fL f max ---------- from the equation ---------- = -------------- ; use ---------- with Fig. 9 to determine the ratio R2/R1 to obtain R1. f min f min f min fo fL b) Given fmin and fmax: use fmin with Fig.8 to determine R2 and C1; calculate f max f max ---------- ; use ---------f min f min with Fig.9 to determine R2/R1 to obtain R1.
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Philips Semiconductors
Product specification
Phase-locked loop
HEF4046B MSI
Fig.7
Typical centre frequency as a function of capacitor C1; Tamb = 25 °C; VCOIN at 1/2 VDD; INH at VSS; R2 = .
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Philips Semiconductors
Product specification
Phase-locked loop
HEF4046B MSI
Fig.8 Typical frequency offset as a function of capacitor C1; Tamb = 25 °C; VCOIN at VSS; INH at VSS; R1 = .
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Philips Semiconductors
Product specification
Phase-locked loop
HEF4046B MSI
Fig.9 Typical ratio of R2/R1 as a function of the ratio fmax/fmin.
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Philips Semiconductors
Product specification
Phase-locked loop
HEF4046B MSI
Fig.10 Power dissipation as a function of R1; R2 = ; VCOIN at 1/2 VDD; CL = 50 pF.
Fig.11 Power dissipation as a function of R2; R1 = ; VCOIN at VSS (0 V); CL = 50 pF.
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Philips Semiconductors
Product specification
Phase-locked loop
HEF4046B MSI
Fig.12 Power dissipation of source follower as a function of RSF; VCOIN at 1/2 VDD; R1 = ; R2 = .
For VCO linearity: f1 + f2 f o = -------------2 f o fo lin. = --------------- × 100% fo Figure 13 and the above formula also apply to source follower linearity: substitute VSF OUT for f. V = 0,3 V at VDD = 5 V V = 2,5 V at VDD = 10 V V = 5 V at VDD = 15 V
Fig.13 Definition of linearity (see AC characteristics).
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Philips Semiconductors
Product specification
Phase-locked loop
HEF4046B MSI
Fig.14 VCO frequency linearity as a function of R1; R2 = ; VDD = 5 V.
Fig.15 VCO frequency linearity as a function of R1; R2 = ; VDD = 10 V.
Fig.16 VCO frequency linearity as a function of R1; R2 = ; VDD = 15 V.
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