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Электронный компонент: 74HC4046ADB

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DATA SHEET
Product specification
Supersedes data of September 1993
File under Integrated Circuits, IC06
1997 Nov 25
INTEGRATED CIRCUITS
74HC/HCT4046A
Phase-locked-loop with VCO
For a complete data sheet, please also download:
The IC06 74HC/HCT/HCU/HCMOS Logic Family Specifications
The IC06 74HC/HCT/HCU/HCMOS Logic Package Information
The IC06 74HC/HCT/HCU/HCMOS Logic Package Outlines
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1997 Nov 25
2
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
FEATURES
Low power consumption
Centre frequency of up to 17 MHz (typ.) at V
CC
= 4.5 V
Choice of three phase comparators: EXCLUSIVE-OR;
edge-triggered JK flip-flop;
edge-triggered RS flip-flop
Excellent VCO frequency linearity
VCO-inhibit control for ON/OFF keying and for low
standby power consumption
Minimal frequency drift
Operating power supply voltage range:
VCO section 3.0 to 6.0 V
digital section 2.0 to 6.0 V
Zero voltage offset due to op-amp buffering
Output capability: standard
I
CC
category: MSI.
GENERAL DESCRIPTION
The 74HC/HCT4046A are high-speed Si-gate CMOS
devices and are pin compatible with the "4046" of the
"4000B" series. They are specified in compliance with
JEDEC standard no. 7A.
The 74HC/HCT4046A are phase-locked-loop circuits that
comprise a linear voltage-controlled oscillator (VCO) and
three different phase comparators (PC1, PC2 and PC3)
with a common signal input amplifier and a common
comparator input.
The signal input can be directly coupled to large voltage
signals, or indirectly coupled (with a series capacitor) to
small voltage signals. A self-bias input circuit keeps small
voltage signals within the linear region of the input
amplifiers. With a passive low-pass filter, the "4046A"
forms a second-order loop PLL. The excellent VCO
linearity is achieved by the use of linear op-amp
techniques.
The VCO requires one external capacitor C1 (between
C1
A
and C1
B
) and one external resistor R1 (between
R
1
and GND) or two external resistors R1 and R2
(between R
1
and GND, and R
2
and GND). Resistor R1
and capacitor C1 determine the frequency range of the
VCO. Resistor R2 enables the VCO to have a frequency
offset if required.
The high input impedance of the VCO simplifies the design
of low-pass filters by giving the designer a wide choice of
resistor/capacitor ranges. In order not to load the low-pass
filter, a demodulator output of the VCO input voltage is
provided at pin 10 (DEM
OUT
). In contrast to conventional
techniques where the DEM
OUT
voltage is one threshold
voltage lower than the VCO input voltage, here the
DEM
OUT
voltage equals that of the VCO input. If
DEM
OUT
is used, a load resistor (R
S
) should be connected
from DEM
OUT
to GND; if unused, DEM
OUT
should be left
open. The VCO output (VCO
OUT
) can be connected
directly to the comparator input (COMP
IN
), or connected
via a frequency-divider. The VCO output signal has a duty
factor of 50% (maximum expected deviation 1%), if the
VCO input is held at a constant DC level. A LOW level at
the inhibit input (INH) enables the VCO and demodulator,
while a HIGH level turns both off to minimize standby
power consumption.
The only difference between the HC and HCT versions is
the input level specification of the INH input. This input
disables the VCO section. The sections of the comparator
are identical, so that there is no difference in the
SIG
IN
(pin 14) or COMP
IN
(pin 3) inputs between the HC
and HCT versions.
Phase comparators
The signal input (SIG
IN
) can be directly coupled to the
self-biasing amplifier at pin 14, provided that the signal
swing is between the standard HC family input logic levels.
Capacitive coupling is required for signals with smaller
swings.
Phase comparator 1 (PC1)
This is an EXCLUSIVE-OR network. The signal and
comparator input frequencies (f
i
) must have a 50% duty
factor to obtain the maximum locking range. The transfer
characteristic of PC1, assuming ripple (f
r
= 2f
i
) is
suppressed, is:
where V
DEMOUT
is the demodulator output at pin 10;
V
DEMOUT
= V
PC1OUT
(via low-pass filter).
The phase comparator gain is:
The average output voltage from PC1, fed to the VCO
input via the low-pass filter and seen at the demodulator
output at pin 10 (V
DEMOUT
), is the resultant of the phase
differences of signals (SIG
IN
) and the comparator input
(COMP
IN
) as shown in Fig.6. The average of V
DEMOUT
is
equal to
1
/
2
V
CC
when there is no signal or noise at
SIG
IN
and with this input the VCO oscillates at the centre
frequency (f
o
). Typical waveforms for the PC1 loop locked
at f
o
are shown in Fig.7.
V
DEMOUT
V
CC
-----------
SIGIN
COMPIN
(
)
=
K
p
V
CC
----------- V r
/
(
)
.
=
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1997 Nov 25
3
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
The frequency capture range (2f
c
) 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
(2f
L
) 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 PC1, the capture range depends on the low-pass
filter characteristics and can be made as large as the lock
range.
This configuration retains lock even with very noisy input
signals. Typical behaviour of this type of phase
comparator is that it can lock to input frequencies close to
the harmonics of the VCO centre frequency.
Phase comparator 2 (PC2)
This is a positive edge-triggered phase and frequency
detector. When the PLL is using this comparator, the loop
is controlled by positive signal transitions and the duty
factors of SIG
IN
and COMP
IN
are not important. PC2
comprises two D-type flip-flops, control-gating and a
3-state output stage. The circuit functions as an up-down
counter (Fig.5) where SIG
IN
causes an up-count and
COMP
IN
a down-count. The transfer function of PC2,
assuming ripple (f
r
= f
i
) is suppressed,
is:
where V
DEMOUT
is the demodulator output at pin 10;
V
DEMOUT
= V
PC2OUT
(via low-pass filter).
The phase comparator gain is:
V
DEMOUT
is the resultant of the initial phase differences of
SIG
IN
and COMP
IN
as shown in Fig.8. Typical waveforms
for the PC2 loop locked at f
o
are shown in Fig.9.
When the frequencies of SIG
IN
and COMP
IN
are equal but
the phase of SIG
IN
leads that of COMP
IN
, the p-type
output driver at PC2
OUT
is held "ON" for a time
corresponding to the phase difference (
DEMOUT
). When
the phase of SIG
IN
lags that of COMP
IN
, the n-type driver
is held "ON".
When the frequency of SIG
IN
is higher than that of
COMP
IN
, the p-type output driver is held "ON" for most of
the input signal cycle time, and for the remainder of the
cycle both n and p- type drivers are "OFF" (3-state). If the
SIG
IN
frequency is lower than the COMP
IN
frequency, then
it is the n-type driver that is held "ON" for most of the cycle.
Subsequently, the voltage at the capacitor (C2) of the
low-pass filter connected to PC2
OUT
varies until the signal
V
DEMOUT
V
CC
4
-----------
SIGIN
COMPIN
(
)
=
K
p
V
CC
4
----------- V r
/
(
)
.
=
and comparator inputs are equal in both phase and
frequency. At this stable point the voltage on C2 remains
constant as the PC2 output is in 3-state and the VCO input
at pin 9 is a high impedance. Also in this condition, the
signal at the phase comparator pulse output (PCP
OUT
) is a
HIGH level and so can be used for indicating a locked
condition.
Thus, for PC2, no phase difference exists between
SIG
IN
and COMP
IN
over the full frequency range of the
VCO. Moreover, the power dissipation due to the low-pass
filter is reduced because both p and n-type 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 and is independent of the
low-pass filter. With no signal present at SIG
IN
the
VCO adjusts, via PC2, to its lowest frequency.
Phase comparator 3 (PC3)
This is a positive edge-triggered sequential phase detector
using an RS-type flip-flop. When the PLL is using this
comparator, the loop is controlled by positive signal
transitions and the duty factors of SIG
IN
and COMP
IN
are
not important. The transfer characteristic of PC3,
assuming ripple (f
r
= f
i
) is suppressed,
is:
where V
DEMOUT
is the demodulator output at pin 10;
V
DEMOUT
= V
PC3OUT
(via low-pass filter).
The phase comparator gain is:
The average output from PC3, fed to the VCO via the
low-pass filter and seen at the demodulator output at
pin 10 (V
DEMOUT
), is the resultant of the phase differences
of SIG
IN
and COMP
IN
as shown in Fig.10. Typical
waveforms for the PC3 loop locked at f
o
are shown in
Fig.11.
The phase-to-output response characteristic of PC3
(Fig.10) differs from that of PC2 in that the phase angle
between SIG
IN
and COMP
IN
varies between 0
and
360
and is 180
at the centre frequency. Also PC3 gives
a greater voltage swing than PC2 for input phase
differences but as a consequence the ripple content of the
VCO input signal is higher. The PLL lock range for this type
of phase comparator and the capture range are dependent
on the low-pass filter. With no signal present at SIG
IN
the
VCO adjusts, via PC3, to its lowest frequency.
V
DEMOUT
V
CC
2
-----------
SIGIN
COMPIN
(
)
=
K
p
V
CC
2
----------- V r
/
(
)
.
=
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1997 Nov 25
4
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
QUICK REFERENCE DATA
GND = 0 V; T
amb
= 25
C
Notes
1. C
PD
is used to determine the dynamic power dissipation (P
D
in
W):
P
D
= C
PD
V
CC
2
f
i
+
(C
L
V
CC
2
f
o
) where:
f
i
= input frequency in MHz.
f
o
= output frequency in MHz.
C
L
= output load capacitance in pF.
V
CC
= supply voltage in V.
(C
L
V
CC
2
f
o
) = sum of outputs.
2. Applies to the phase comparator section only (VCO disabled). For power dissipation of the VCO and demodulator
sections see Figs 22, 23 and 24.
ORDERING INFORMATION
See
"74HC/HCT/HCU/HCMOS Logic Package Information"
.
APPLICATIONS
FM modulation and demodulation
Frequency synthesis and multiplication
Frequency discrimination
Tone decoding
Data synchronization and conditioning
Voltage-to-frequency conversion
Motor-speed control.
PACKAGE OUTLINES
See
"74HC/HCT/HCU/HCMOS Logic Package Outlines"
.
SYMBOL
PARAMETER
CONDITIONS
TYPICAL
UNIT
HC
HCT
f
o
VCO centre frequency
C1 = 40 pF; R1 = 3 k
; V
CC
= 5 V 19
19
MHz
C
I
input capacitance (pin 5)
3.5
3.5
pF
C
PD
power dissipation capacitance per
package
notes 1 and 2
24
24
pF
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1997 Nov 25
5
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
PIN DESCRIPTION
PIN NO.
SYMBOL
NAME AND FUNCTION
1
PCP
OUT
phase comparator pulse output
2
PC1
OUT
phase comparator 1 output
3
COMP
IN
comparator input
4
VCO
OUT
VCO output
5
INH
inhibit input
6
C1
A
capacitor C1 connection A
7
C1
B
capacitor C1 connection B
8
GND
ground (0 V)
9
VCO
IN
VCO input
10
DEM
OUT
demodulator output
11
R
1
resistor R1 connection
12
R
2
resistor R2 connection
13
PC2
OUT
phase comparator 2 output
14
SIG
IN
signal input
15
PC3
OUT
phase comparator 3 output
16
V
CC
positive supply voltage
Fig.1 Pin configuration.
Fig.2 Logic symbol.
Fig.3 IEC logic symbol.
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1997 Nov 25
6
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
MGA847
PHASE
COMPARATOR
2
LOCK
DETECTOR
PC2 OUT
LD
13
1
identical to 4046A
CLD
C
CLD
15
7046A
PHASE
COMPARATOR
2
PC2 OUT 13
PHASE
COMPARATOR
3
PC3 OUT 15
PHASE
COMPARATOR
1
PC1 OUT 2
PCPOUT 1
SIG IN
COMP IN
VCO OUT
C1A
C1B
DEMOUT
INH
VCO IN
R2
R1
R2
12
11
3
14
4
7
6
5
10
9
(a)
(b)
C1
4046A
VCO
R S
R1
R4
R3
C2
Fig.4 Functional diagram.
(a)
(b)
Fig.5 Logic diagram.
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1997 Nov 25
7
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
Fig.6 Phase comparator 1: average output voltage versus input phase difference.
V
DEMOUT
= V
PC2OUT
=
DEMOUT
= (
SIGIN
-
COMPIN
).
V
CC
-----------
SIGIN
COMPIN
(
)
Fig.7 Typical waveforms for PLL using phase comparator 1, loop locked at f
o
.
Fig.8 Phase comparator 2: average output voltage versus input phase difference.
V
DEMOUT
= V
PC2OUT
=
DEMOUT
= (
SIGIN
-
C
OMPIN
).
V
CC
4
-----------
SIGIN
COMPIN
(
)
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1997 Nov 25
8
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
Fig.9 Typical waveforms for PLL using phase comparator 2, loop locked at f
o
.
Fig.10 Phase comparator 3: average output voltage versus input phase difference:
V
DEMOUT
= V
PC3OUT
=
DEMOUT
= (
SIGIN
-
COMPIN
).
V
CC
2
-----------
SIGIN
COMPIN
(
)
Fig.11 Typical waveforms for PLL using phase comparator 3, loop locked at f
o
.
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1997 Nov 25
9
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
RECOMMENDED OPERATING CONDITIONS FOR 74HC/HCT
RATINGS
Limiting values in accordance with the Absolute Maximum System (IEC 134)
Voltages are referenced to GND (ground = 0 V)
SYMBOL
PARAMETER
74HC
74HCT
UNIT
CONDITIONS
min. typ. max. min.
typ.
max.
V
CC
DC supply voltage
3.0
5.0
6.0
4.5
5.0
5.5
V
V
CC
DC supply voltage if VCO
section is not used
2.0
5.0
6.0
4.5
5.0
5.5
V
V
I
DC input voltage range
0
V
CC
0
V
CC
V
V
O
DC output voltage range
0
V
CC
0
V
CC
V
T
amb
operating ambient
temperature range
-
40
+85
-
40
+85
C
see DC and AC
CHARACTERISTICS
T
amb
operating ambient
temperature range
-
40
+125
-
40
+
125
C
t
r
, t
f
input rise and fall times (pin 5)
6.0
1000
6.0
500
ns
V
CC
= 2.0 V
6.0
500
6.0
500
ns
V
CC
= 4.5 V
6.0
400
6.0
500
ns
V
CC
= 6.0 V
SYMBOL
PARAMETER
MIN.
MAX.
UNIT
CONDITIONS
V
CC
DC supply voltage
-
0.5
+7
V
I
IK
DC input diode current
20
mA
for V
I
< -
0.5 V or V
I
>
V
CC
+ 0.5 V
I
OK
DC output diode current
20
mA
for V
O
< -
0.5 V or V
O
>
V
CC
+ 0.5 V
I
O
DC output source or sink
current
25
mA
for
-
0.5 V
<
V
O
<
V
CC
+ 0.5 V
I
CC
;
I
GND
DC V
CC
or GND current
50
mA
T
stg
storage temperature range
-
65
+150
C
P
tot
power dissipation per package
plastic DIL
750
mW
for temperature range:
-
40 to +125
C
74HC/HCT
above + 70
C: derate linearly with 12 mW/K
plastic mini-pack (SO)
500
mW
above + 70
C: derate linearly with 8 mW/K
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1997 Nov 25
10
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
DC CHARACTERISTICS FOR 74HC
Quiescent supply current
Voltages are referenced to GND (ground = 0 V)
Phase comparator section
Voltages are referenced to GND (ground = 0 V)
SYMBOL PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HC
V
CC
(V)
OTHER
+25
-
40 to +85
-
40 to +125
min. typ. max.
min. max.
min.
max.
I
CC
quiescent supply
current (VCO
disabled)
8.0
80.0
160.0
A
6.0
pins 3, 5, and 14 at V
CC
;
pin 9 at GND; I
I
at pins
3 and 14 to be excluded
SYM-
BOL
PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HC
V
CC
(V)
V
I
OTHER
+25
-
40 to +85
-
40 to +125
min.
typ.
max. min.
max.
min.
max.
V
IH
DC coupled
HIGH level input voltage
SIG
IN
, COMP
IN
1.5
1.2
1.5
1.5
V
2.0
3.15
2.4
3.15
3.15
4.5
4.2
3.2
4.2
4.2
6.0
V
IL
DC coupled
LOW level input voltage
SIG
IN
, COMP
IN
0.8
0.5
0.5
0.5
V
2.0
2.1
1.35
1.35
1.35
4.5
2.8
1.8
1.8
1.8
6.0
V
OH
HIGH level output voltage
PCP
OUT
, PC
nOUT
1.9
2.0
1.9
1.9
V
2.0
V
IH
or
V
IL
-
I
O
= 20
A
4.4
4.5
4.4
4.4
4.5
-
I
O
= 20
A
5.9
6.0
5.9
5.9
6.0
-
I
O
= 20
A
V
OH
HIGH level output voltage
PCP
OUT
, PC
nOUT
3.98
4.32
3.84
3.7
V
4.5
V
IH
or
V
IL
-
I
O
= 4.0 mA
5.48
5.81
5.34
5.2
6.0
-
I
O
= 5.2 mA
V
OL
LOW level output voltage
PCP
OUT
, PC
nOUT
0
0.1
0.1
0.1
V
2.0
V
IH
or
V
IL
I
O
= 20
A
0
0.1
0.1
0.1
4.5
I
O
= 20
A
0
0.1
0.1
0.1
6.0
I
O
= 20
A
V
OL
LOW level output voltage
PCP
OUT
, PC
nOUT
0.15 0.26
0.33
0.4
V
4.5
V
IH
or
V
IL
I
O
= 4.0 mA
0.16 0.26
0.33
0.4
6.0
I
O
= 5.2 mA
I
I
input leakage current
SIG
IN
, COMP
IN
3.0
4.0
5.0
A
2.0
V
CC
or
GND
7.0
9.0
11.0
3.0
18.0
23.0
27.0
4.5
30.0
38.0
45.0
6.0
I
OZ
3-state
OFF-state current
PC2
OUT
0.5
5.0
10.0
A
6.0
V
IH
or
V
IL
V
O
= V
CC
or
GND
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1997 Nov 25
11
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
VCO section
Voltages are referenced to GND (ground = 0 V)
R
I
input resistance
SIG
IN
, COMP
IN
800
k
3.0
V
I
at self-bias
operating point;
V
I
= 0.5 V;
see Figs 12, 13
and 14
250
k
4.5
150
k
6.0
SYM-
BOL
PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HC
V
CC
(V)
V
I
OTHER
+25
-
40 to +85
-
40 to +125
min.
typ.
max. min.
max.
min.
max.
V
IH
HIGH level
input voltage
INH
2.1
1.7
2.1
2.1
V
3.0
3.15
2.4
3.15
3.15
4.5
4.2
3.2
4.2
4.2
6.0
V
IL
LOW level
input voltage
INH
1.3
0.9
0.9
0.9
V
3.0
2.1
1.35
1.35
1.35
4.5
2.8
1.8
1.8
1.8
6.0
V
OH
HIGH level
output voltage
VCO
OUT
2.9
3.0
2.9
2.9
V
3.0
V
IH
or
V
IL
-
I
O
= 20
A
4.4
4.5
4.4
4.4
4.5
-
I
O
= 20
A
5.9
6.0
5.9
5.9
6.0
-
I
O
= 20
A
V
OH
HIGH level
output voltage
VCO
OUT
3.98
4.32
3.84
3.7
V
4.5
V
IH
or
V
IL
-
I
O
= 4.0 mA
5.48
5.81
5.34
5.2
6.0
-
I
O
= 5.2 mA
V
OL
LOW level
output voltage
VCO
OUT
0
0.1
0.1
0.1
V
3.0
V
IH
or
V
IL
I
O
= 20
A
0
0.1
0.1
0.1
4.5
I
O
= 20
A
0
0.1
0.1
0.1
6.0
I
O
= 20
A
V
OL
LOW level
output voltage
VCO
OUT
0.15
0.26
0.33
0.4
V
4.5
V
IH
or
V
IL
I
O
= 4.0 mA
0.16
0.26
0.33
0.4
6.0
I
O
= 5.2 mA
V
OL
LOW level output
voltage C1
A
, C1
B
0.40
0.47
0.54
V
4.5
V
IH
or
V
IL
I
O
= 4.0 mA
0.40
0.47
0.54
6.0
I
O
= 5.2 mA
I
I
input leakage
current
INH, VCO
IN
0.1
1.0
1.0
A
6.0
V
CC
or
GND
R1
resistor range
3.0
300
k
3.0
note 1
3.0
300
4.5
3.0
300
6.0
SYM-
BOL
PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HC
V
CC
(V)
V
I
OTHER
+25
-
40 to +85
-
40 to +125
min.
typ.
max. min.
max.
min.
max.
background image
1997 Nov 25
12
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
Note
1. The parallel value of R1 and R2 should be more than 2.7 k
. Optimum performance is achieved when R1 and/ or
R2 are/is
>
10 k
.
Demodulator section
Voltages are referenced to GND (ground = 0 V)
R
2
resistor range
3.0
300
k
3.0
note 1
3.0
300
4.5
3.0
300
6.0
C1
capacitor range
40
no
limit
pF
3.0
40
4.5
40
6.0
V
VCOIN
operating voltage
range at VCO
IN
1.1
1.9
V
3.0
over the range
specified for
R1; for linearity
see Figs 20
and 21
1.1
3.4
4.5
1.1
4.9
6.0
SYMBOL
PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HC
V
CC
V
OTHER
+25
-
40 to+85
-
40 to +125
min. typ.
max.
min.
max.
min.
max.
R
S
resistor range
50
300
k
3.0
at R
S
>
300 k
the leakage current can
influence V
DEMOUT
50
300
4.5
50
300
6.0
V
OFF
offset voltage
VCO
IN
to V
DEMOUT
30
mV
3.0
V
I
= V
VCOIN
= 1/2 V
CC
;
values taken over
R
S
range; see Fig.15
20
4.5
10
6.0
R
D
dynamic output
resistance at DEM
OUT
25
3.0
V
DEMOUT
= 1/2 V
CC
25
4.5
25
6.0
SYM-
BOL
PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HC
V
CC
(V)
V
I
OTHER
+25
-
40 to +85
-
40 to +125
min.
typ.
max. min.
max.
min.
max.
background image
1997 Nov 25
13
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
AC CHARACTERISTICS FOR 74HC
Phase comparator section
GND = 0 V; t
r
= t
f
= 6 ns; C
L
= 50 pF
SYMBOL PARAMETER
T
amb
(
C)
UNIT
TEST
CONDITIONS
74HC
V
CC
(V)
OTHER
+25
-
40 to +85
-
40 to +125
min.
typ.
max.
min. max.
min.
max.
t
PHL
/
t
PLH
propagation delay
SIG
IN
, COMP
IN
to PC1
OUT
63
200
250
300
ns
2.0
Fig.16
23
40
50
60
4.5
18
34
43
51
6.0
t
PHL
/
t
PLH
propagation delay
SIG
IN
, COMP
IN
to PCP
OUT
96
340
425
510
ns
2.0
Fig.16
35
68
85
102
4.5
28
58
72
87
6.0
t
PHL
/
t
PLH
propagation delay
SIG
IN
, COMP
IN
to PC3
OUT
77
270
340
405
ns
2.0
Fig.16
28
54
68
81
4.5
22
46
58
69
6.0
t
PZH
/
t
PZL
3-state output enable
time SIG
IN
, COMP
IN
to PC2
OUT
83
280
350
420
ns
2.0
Fig.17
30
56
70
84
4.5
24
48
60
71
6.0
t
PHZ
/
t
PLZ
3-state output disable
time SIG
IN
, COMP
IN
to PC2
OUT
99
325
405
490
ns
2.0
Fig.17
36
65
81
98
4.5
29
55
69
83
6.0
t
THL
/
t
TLH
output transition time
19
75
95
110
ns
2.0
Fig.16
7
15
19
22
4.5
6
13
16
19
6.0
V
I(p-p)
AC coupled input sensitivity
(peak-to-peak value) at
SIG
IN
or COMP
IN
9
mV
2.0
f
i
= 1 MHz
11
3.0
15
4.5
33
6.0
background image
1997 Nov 25
14
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
VCO section
GND = 0 V; t
r
= t
f
= 6 ns; C
L
= 50 pF
DC CHARACTERISTICS FOR 74HCT
Quiescent supply current
Voltages are referenced to GND (ground = 0 V)
Note
1. The value of additional quiescent supply current (
I
CC
) for a unit load of 1 is given above.
To determine
I
CC
per input, multiply this value by the unit load coefficient shown in the table below.
SYMBOL PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HC
V
CC
(V)
OTHER
+25
-
40 to +85
-
40 to +125
min.
typ. max. typ.
max.
min.
max.
f/T
frequency stability
with temperature
change
0.20
%/K
3.0
V
I
= V
VCOIN
= 1/2 V
CC
;
R1 = 100 k
; R2 =
;
C1 = 100 pF; see Fig.18
0.15
4.5
0.14
6.0
f
o
VCO centre
frequency (duty
factor = 50%)
7.0
10.0
MHz
3.0
V
VCOIN
= 1/2 V
CC
;
R1 = 3 k
; R2 =
;
C1 = 40 pF; see Fig.19
11.0
17.0
4.5
13.0
21.0
6.0
f
VCO
VCO frequency
linearity
1.0
%
3.0
R1 = 100 k
; R2 =
;
C1 = 100 pF;
see Figs 20 and 21
0.4
4.5
0.3
6.0
VCO
duty factor at
VCO
OUT
50
%
3.0
50
4.5
50
6.0
SYMBOL PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HCT
V
CC
(V)
OTHER
+25
-
40 to +85
-
40 to +125
min. typ. max. min. max. min.
max.
I
CC
quiescent supply
current
(VCO disabled)
8.0
80.0
160.0
A
6.0
pins 3, 5 and 14
at V
CC
; pin 9 at
GND; I
I
at
pins 3 and 14 to
be excluded
I
CC
additional quiescent
supply current per
input pin for unit load
coefficient is 1 (note 1)
V
I
= V
CC
-
2.1 V
100
360
450
490
A
4.5
to
5.5
pins 3 and 14
at V
CC
;
pin 9 at GND;
I
I
at pins 3 and 14
to be excluded
INPUT
UNIT LOAD COEFFICIENT
INH
1.00
background image
1997 Nov 25
15
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
DC CHARACTERISTICS FOR 74HCT
Phase comparator section
Voltages are referenced to GND (ground = 0 V)
SYMBOL PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HCT
V
CC
(V)
V
I
OTHER
+25
-
40 to +85
-
40 to +125
min
typ. max min
max
min.
max.
V
IH
DC coupled
HIGH level input
voltage SIG
IN
, COMP
IN
3.15
2.4
V
4.5
V
IL
DC coupled
LOW level input
voltage
SIG
IN
, COMP
IN
2.1
1.35
V
4.5
V
OH
HIGH level output
voltage PCP
OUT
,
PC
nOUT
4.4
4.5
4.4
4.4
V
4.5
V
IH
or
V
IL
-
I
O
= 20
A
V
OH
HIGH level output
voltage PCP
OUT
,
PC
nOUT
3.98
4.32
3.84
3.7
V
4.5
V
IH
or
V
IL
-
I
O
= 4.0 mA
V
OL
LOW level output
voltage
PCP
OUT
, PC
nOUT
0
0.1
0.1
0.1
V
4.5
V
IH
or
V
IL
I
O
= 20
A
V
OL
LOW level output
voltage
PCP
OUT
, PC
nOUT
0.15 0.26
0.33
0.4
V
4.5
V
IH
or
V
IL
I
O
= 4.0 mA
I
I
input leakage current
SIG
IN
, COMP
IN
30
38
45
A
5.5
V
CC
or
GN
D
I
OZ
3-state OFF-state
current PC2
OUT
0.5
5.0
10.0
A
5.5
V
IH
or
V
IL
V
O
= V
CC
or
GND
R
I
input resistance
SIG
IN
, COMP
in
250
k
4.5
V
I
at self-bias
operating
point;
V
I
= 0.5 V;
see Figs 12
, 13
and
14
background image
1997 Nov 25
16
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
DC CHARACTERISTICS FOR 74HCT
VCO section
Voltages are referenced to GND (ground = 0 V)
Note
1. The parallel value of R1 and R2 should be more than 2.7 k
. Optimum performance is achieved when R1 and/or R2
are/is
>
10 k
.
SYMBOL
PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HCT
V
CC
(V)
V
I
OTHER
+25
-
40 to +85
-
40 to +125
min
typ.
max
min
max
min.
max.
V
IH
HIGH level
input voltage INH
2.0
1.6
2.0
2.0
V
4.5
to
5.5
V
IL
LOW level
input voltage INH
1.2
0.8
0.8
0.8
V
4.5
to
5.5
V
OH
HIGH level output
voltage VCO
OUT
4.4
4.5
4.4
4.4
V
4.5
V
IH
or
V
IL
-
I
O
= 20
A
V
OH
HIGH level output
voltage VCO
OUT
3.98
4.32
3.84
3.7
V
4.5
V
IH
or
V
IL
-
I
O
= 4.0 mA
V
OL
LOW level output
voltage VCO
OUT
0
0.1
0.1
0.1
V
4.5
V
IH
or
V
IL
I
O
= 20
A
V
OL
LOW level output
voltage VCO
OUT
0.15 0.26
0.33
0.4
V
4.5
V
IH
or
V
IL
I
O
= 4.0 mA
V
OL
LOW level output
voltage C1
A
, C1
B
(test purposes only)
0.40
0.47
0.54
V
4.5
V
IH
or
V
IL
I
O
= 4.0 mA
I
I
input leakage
current
INH, VCO
IN
0.1
1.0
1.0
A
5.5
V
CC
or
GND
R1
resistor range
3.0
300
k
4.5
note 1
R
2
resistor range
3.0
300
k
4.5
note 1
C1
capacitor range
40
no
limit
pF
4.5
V
VCOIN
operating voltage
range at VCO
IN
1.1
3.4
V
4.5
over the
range
specified for
R1; for
linearity see
Figs 20
and 21
background image
1997 Nov 25
17
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
DC CHARACTERISTICS FOR 74HCT
Demodulator section
Voltages are referenced to GND (ground = 0 V)
AC CHARACTERISTICS FOR 74HCT
Phase comparator section
GND = 0 V; t
r
= t
f
= 6 ns; C
L
= 50 pF
SYMBOL
PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HCT
V
CC
(V)
OTHER
+25
-
40 to +85
-
40 to +125
min. typ. max. min. max.
min.
max.
R
S
resistor range
50
300
k
4.5
at R
S
>
300 k
the leakage current can
influence V
DEMOUT
V
OFF
offset voltage
VCO
IN
to
V
DEMOUT
20
mV
4.5
V
I
= V
VCOIN
= 1/2 V
CC
;
values taken over
R
S
range; see Fig.15
R
D
dynamic output
resistance at
DEM
OUT
25
4.5
V
DEMOUT
= 1/2 V
CC
SYMBOL
PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HCT
V
CC
(V)
OTHER
+25
-
40 to +85
-
40 to +125
min.
typ.
max.
min.
max.
min.
max.
t
PHL
/
t
PLH
propagation delay
SIG
IN
, COMP
IN
to PC1
OUT
23
40
50
60
ns
4.5
Fig.16
t
PHL
/
t
PLH
propagation delay
SIG
IN
, COMP
IN
to PCP
OUT
35
68
85
102
ns
4.5
Fig.16
t
PHL
/
t
PLH
propagation delay
SIG
IN
, COMP
IN
to PC3
OUT
28
54
68
81
ns
4.5
Fig.16
t
PZH
/
t
PZL
3-state output enable
time SIG
IN
, COMP
IN
to PC2
OUT
30
56
70
84
ns
4.5
Fig.17
background image
1997 Nov 25
18
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
VCO section
GND = 0 V; t
r
= t
f
= 6 ns; C
L
= 50 pF
t
PHZ
/
t
PLZ
3-state output disable
time SIG
IN
, COMP
IN
to PC2
OUT
36
65
81
98
ns
4.5
Fig.17
t
THL
/
t
TLH
output transition time
7
15
19
22
ns
4.5
Fig.16
V
I (p-p)
AC coupled input
sensitivity
(peak-to-peak value)
at
SIG
IN
or COMP
IN
15
mV
4.5
f
i
= 1 MHz
SYMBOL
PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HCT
V
CC
(V)
OTHER
+25
-
40 to +85
-
40 to +125
min.
typ.
max
min.
max
min.
max.
f/T
frequency stability
with temperature
change
0.15
%/K
4.5
V
I
= V
VCOIN
withi
n recommended
range;
R1 = 100 k
;
R2 =
;
C1 = 100 pF;
see Fig.18b
f
o
VCO centre frequency
(duty factor = 50%)
11.0
17.0
MHz
4.5
V
VCOIN
= 1/2 V
CC
;
R1 = 3 k
;
R2 =
;
C1 = 40 pF;
see Fig.19
f
VCO
VCO frequency
linearity
0.4
%
4.5
R1 = 100 k
;
R2 =
;
C1 = 100 pF;
see Figs 20
and 21
VCO
duty factor at VCO
OUT
50
%
4.5
SYMBOL
PARAMETER
T
amb
(
C)
UNIT
TEST CONDITIONS
74HCT
V
CC
(V)
OTHER
+25
-
40 to +85
-
40 to +125
min.
typ.
max.
min.
max.
min.
max.
background image
1997 Nov 25
19
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
FIGURE REFERENCES FOR DC CHARACTERISTICS
Fig.12 Typical input resistance curve at SIG
IN
,
COMP
IN
.
Fig.13 Input resistance at SIG
IN
, COMP
IN
with
V
I
= 0.5 V at self-bias point.
Fig.14 Input current at SIG
IN
, COMP
IN
with
V
I
= 0.5 V at self-bias point.
Fig.15 Offset voltage at demodulator output as a
function of VCO
IN
and R
S
.
R
S
= 50 k
- - - - R
S
= 300 k
background image
1997 Nov 25
20
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
AC WAVEFORMS
Fig.16 Waveforms showing input (SIG
IN
, COMP
IN
) to output (PCP
OUT
, PC1
OUT
, PC3
OUT
) propagation delays
and the output transition times.
(1) HC : V
M
= 50%; V
I
= GND to V
CC
Fig.17 Waveforms showing the 3-state enable and disable times for PC2
OUT
.
(1) HC : V
M
= 50%; V
I
= GND to V
CC
background image
1997
Nov
25
21
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
Fig.18 Frequency stability of the VCO as a function of ambient temperature with supply voltage as a parameter.
without offset (R2 =
): (a) R1 = 3 k
; (b) R1 = 10 k
; (c) R1 = 300 k
.
- - -
with offset
(R1 =
): (a) R2 = 3 k
; (b) R2 = 10 k
; (c) R2 = 300 k
.
In (b), the frequency stability for R1 = R2 = 10 k
at 5 V is also given (curve A). This curve is set by the total VCO bias current, and is
not simply the addition of the two 10 k
stability curves. C1 = 100 pF; V
VCO IN
= 0.5 V
CC
.
To obtain optimum temperature stability, C1 must be as small as possible but larger than 100 pF.
book, halfpage
MSB710
Tamb (
o
C)
0
150
100
50
0
-
50
-
25
-
20
-
15
-
10
-
5
5
10
15
20
25
f
(%)
5 V
6 V
3 V
4.5 V
5 V
6 V
V =
CC
3 V
(a)
handbook, halfpage
MSB711
T ( C)
amb
0
f
(%)
o
150
100
50
0
50
25
20
15
10
5
5
10
15
20
25
5 V
6 V
3 V
5 V
6 V
V =
CC
3 V
(b)
A
handbook, halfpage
MSB712
T ( C)
amb
0
f
(%)
o
150
100
50
0
50
25
20
15
10
5
5
10
15
20
25
5 V
6 V
(c)
V =
CC
3 V
3 V
6 V
5 V
background image
1997 Nov 25
22
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
Fig.18 Continued.
(d) R
2
= 3 k
R
1
=
(e) R
2
= 10 k
R
1
=
(f) R
2
= 300 k
R
1
=
To obtain optimum temperature stability, C1 must be as small as possible but larger than 100 pF.
background image
1997 Nov 25
23
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
Fig.19 Graphs showing VCO frequency (f
VCO
) as a function of the VCO input voltage (V
VCOIN
).
(a) R
1
= 3 k
;
C
1
= 40 pF
(c) R
1
= 300 k
;
C
1
= 40 pF
(d) R
1
= 300 k
;
C
1
= 100 nF
(b) R
1
= 3 k
;
C
1
= 100 nF
To obtain optimum temperature stability, C1 must be as small as possible but larger than 100 pF.
background image
1997 Nov 25
24
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
Fig.20 Definition of VCO frequency linearity:
V = 0.5 V over the V
CC
range:
for VCO linearity
f`
0
f
1
f
2
+
2
---------------
=
linearity
f`
0
f
0
f`
0
----------------
100%
=
Fig.21 Frequency linearity as a function of R1, C1
and V
CC
: R2 =
and
V = 0.5 V.
Fig.22 Power dissipation
versus the value of R1:
C
L
= 50 pF;
R2 =
;
V
VCOIN
= 1/2 V
CC
;
T
amb
= 25
C.
C1 = 40 pF
- - - -C1 = 1
F
Fig.23 Power dissipation
versus the value of R2:
C
L
= 50 pF;
R1 =
;
V
VCOIN
= GND = 0 V;
T
amb
= 25
C.
C1 = 40 pF
- - - - C1 = 1
F
Fig.24 Typical dc power
dissipation of
demodulator sections
as a function of R
S
:
R1 = R2 =
;
T
amb
= 25
C;
V
VCOIN
= 1/2 V
CC
.
background image
1997 Nov 25
25
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
APPLICATION INFORMATION
This information is a guide for the approximation of values of external components to be used with the 74HC/HCT4046A
in a phase-lock-loop system.
References should be made to Figs 29, 30 and 31 as indicated in the table.
Values of the selected components should be within the following ranges:
R1
between 3 k
and 300 k
;
R2
between 3 k
and 300 k
;
R1 + R2 parallel value
>
2.7 k
;
C1
greater than 40 pF.
SUBJECT
PHASE
COMPARATOR
DESIGN CONSIDERATIONS
VCO frequency characteristic
VCO frequency
without extra
offset
PC1, PC2 or PC3
With R2 =
and R1 within the range 3 k
<
R1
<
300 k
, the
characteristics of the VCO operation will be as shown in Fig.25.
(Due to R1, C1 time constant a small offset remains when R2 =
.).
Fig.25 Frequency characteristic of VCO operating without offset:
f
0
= centre frequency; 2f
L
= frequency lock range.
Selection of R1 and C1
PC1
Given f
o
, determine the values of R1 and C1 using Fig.29.
PC2 or PC3
Given f
max
and f
o
, determine the values of R1 and C1 using Fig.29, use
Fig.31 to obtain 2f
L
and then use this to calculate f
min
.
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1997 Nov 25
26
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
VCO frequency characteristic
VCO frequency
with extra
offset
PC1, PC2 or PC3
With R1 and R2 within the ranges 3 k
<
R1
<
300 k
,
3 k
<
R2
<
300 k
, the characteristics of the VCO operation will be as
shown in Fig.26.
Fig.26 Frequency characteristic of VCO operating with offset:
f
o
= centre frequency; 2f
L
= frequency lock range.
Selection of R1, R2 and C1
PC1, PC2 or PC3
Given f
o
and f
L
, determine the value of product R1C1 by using Fig.31.
Calculate f
off
from the equation f
off
= f
o
1.6f
L
.
Obtain the values of C1 and R2 by using Fig.30.
Calculate the value of R1 from the value of C1 and the product R1C1.
PLL conditions
with no signal at
the SIG
IN
input
PC1
VCO adjusts to f
o
with
DEMOUT
= 90
and V
VCOIN
= 1/2 V
CC
(see Fig.6).
PC2
VCO adjusts to f
o
with
DEMOUT
=
-
360
and V
VCOIN
= min. (see Fig.8).
PC3
VCO adjusts to f
o
with
DEMOUT
=
-
360
and V
VCOIN
= min. (see Fig.10).
SUBJECT
PHASE
COMPARATOR
DESIGN CONSIDERATIONS
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1997 Nov 25
27
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
PLL frequency
capture range
PC1, PC2 or PC3
Loop filter component selection
(a)
= R3 x C2 (b) amplitude characteristic (c) pole-zero diagram
A small capture range (2f
c
) is obtained if
Fig. 27 Simple loop filter for PLL without offset; R3
500
.
(a)
1 = R3 x C2; (b) amplitude characteristic (c) pole-zero diagram
2 = R4 x C2;
3 = (R3 + R4) x C2
Fig.28 Simple loop filter for PLL with offset; R3 + R4
500
.
PLL locks on
harmonics at
centre frequency
PC1 or PC3
yes
PC2
no
noise rejection at
signal input
PC1
high
PC2 or PC3
low
AC ripple content
when PLL is
locked
PC1
f
r
= 2f
i
, large ripple content at
DEMOUT
= 90
PC2
f
r
= f
i
, small ripple content at
DEMOUT
= 0
PC3
f
r
= f
i
, large ripple content at
DEMOUT
= 180
SUBJECT
PHASE
COMPARATOR
DESIGN CONSIDERATIONS
2f
c
1
--- 2
f
L
/
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1997 Nov 25
28
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
Fig.29 Typical value of VCO centre frequency (f
o
) as a function of C1: R2 =
; V
VCOIN
= 1/2 V
CC
; INH = GND;
T
amb
= 25
C.
To obtain optimum VCO performance, C1 must be as small as possible but larger than 100 pF.
Interpolation for various values of R1 can be easily calculated because a constant R1C1 product will produce almost the same VCO output frequency.
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1997 Nov 25
29
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
Fig.30 Typical value of frequency offset as a function of C1: R1 =
; V
VCOIN
= 1/2 V
CC
; INH = GND; T
amb
= 25
C.
To obtain optimum VCO performance, C1 must be as small as possible but larger than 100 pF.
Interpolation for various values of R2 can be easily calculated because a constant R2C1 product will produce almost the same VCO output frequency.
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1997 Nov 25
30
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
Fig.31 Typical frequency lock range (2f
L
) versus the product R1C1: V
VCOIN
range = 0.9 to (V
CC
-
0.9) V;
R2 =
; VCO gain:
K
V
2f
L
V
VCOIN
range
------------------------------------- 2
r s V
/
/
(
)
.
=
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1997 Nov 25
31
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
PLL design example
The frequency synthesizer, used in
the design example shown in Fig.32,
has the following parameters:
Output frequency: 2 MHz to 3 MHz
frequency steps : 100 kHz
settling time
:
1 ms
overshoot
:
<
20%
The open-loop gain is
H (s) x G (s) = K
p
K
f
K
o
K
n
.
Where:
K
p
= phase comparator gain
K
f
= low-pass filter transfer gain
K
o
= K
v
/s VCO gain
K
n
= 1/n divider ratio
The programmable counter ratio
K
n
can be found as follows:
The VCO is set by the values of R1,
R2 and C1, R2 = 10 k
(adjustable).
The values can be determined using
the information in the section
"DESIGN CONSIDERATIONS".
With f
o
= 2.5 MHz and f
L
= 500 kHz
this gives the following values
(V
CC
= 5.0 V):
R1 = 10 k
R2 = 10 k
C1 = 500 pF
N
min.
f
out
f
step
-----------
2 MHz
100 kHz
----------------------
20
=
=
=
N
max.
f
out
f
step
-----------
3 MHz
100 kHz
----------------------
30
=
=
=
The VCO gain is:
The gain of the phase
comparator is:
The transfer gain of the filter is
given by:
Where:
The characteristics equation is:
1 + H (s)
G (s) = 0.
This results in:
The natural frequency
n
is
defined as follows:
K
v
2f
L
2
0.9
V
CC
0.9
(
)
-----------------------------------------------
=
=
1 MHz
3.2
-----------------
2
2
10
6
r/s/V
=
K
p
V
CC
4
------------
0.4 V/r.
=
=
K
f
1
2
s
+
1
1
2
+
(
)
s
+
------------------------------------- .
=
1
R3C2 and
2
R4C2.
=
=
s
2
1
K
p
K
v
K
n
2
+
1
2
+
(
)
----------------------------------------------------- s+
+
K
p
K
v
K
n
1
2
+
(
)
--------------------------------
0.
=
n
K
p
K
v
K
n
1
2
+
(
)
-------------------------------- .
=
and the damping value
is defined as
follows:
In Fig.33 the output frequency response to
a step of input frequency is shown.
The overshoot and settling time
percentages are now used to determine
n
. From Fig.33 it can be seen that the
damping ratio
= 0.45 will produce an
overshoot of less than 20% and settle to
within 5% at
n
t = 5. The required settling
time is 1 ms.
This results in:
Rewriting the equation for natural
frequency results in:
The maximum overshoot occurs at N
max
.:
When C2 = 470 nF, then
now R3 can be calculated:
1
2
n
----------
1
K
p
K
v
K
n
2
+
1
2
+
(
)
-----------------------------------------------------
=
n
5
t
---
5
0.001
---------------
5
10
3
r/s.
=
=
=
1
2
+
(
)
K
p
K
v
K
n
n
2
-------------------------------- .
=
1
2
+
(
)
0.4
2
10
6
5000
2
30
---------------------------------
0.0011 s.
=
=
R4
1
2
+
(
)
2
n
1
K
p
K
v
K
n
C2
-----------------------------------------------------------------
315
=
=
R3
1
C2
--------
R4 = 2 k
.
=
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1997 Nov 25
32
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
Fig.32 Frequency synthesizer.
note
For an extensive description and application example
please refer to application note ordering number
9398 649 90011.
Also available a computer design program for PLL's
ordering number 9398 961 10061.
Fig.33 Type 2, second order frequency step response.
full pagewidth
0
1
2
4
1.6
1.0
0.6
0
0.8
MSB740
3
1.4
1.2
0.4
0.2
5
6
7
8
nt
0.6
0
0.4
1.0
0.2
0.4
0.2
0.6
0.8
= 5.0
0.5
0.707
1.0
= 0.3
= 2.0
e/
n
e (t)
e/
n
e (t)
Since the output frequency is proportional to the VCO
control voltage, the PLL frequency response can be
observed with an oscilloscope by monitoring pin 9 of the
VCO. The average frequency response, as calculated by
the Laplace method, is found experimentally by smoothing
this voltage at pin 9 with a simple RC filter, whose time
constant is long compared to the phase detector sampling
rate but short compared to the PLL response time.
Fig.34 Frequency compared to the time response.
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1997 Nov 25
33
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
SOLDERING
Introduction
There is no soldering method that is ideal for all IC
packages. Wave soldering is often preferred when
through-hole and surface mounted components are mixed
on one printed-circuit board. However, wave soldering is
not always suitable for surface mounted ICs, or for
printed-circuits with high population densities. In these
situations reflow soldering is often used.
This text gives a very brief insight to a complex technology.
A more in-depth account of soldering ICs can be found in
our
"IC Package Databook" (order code 9398 652 90011).
DIP
S
OLDERING BY DIPPING OR BY WAVE
The maximum permissible temperature of the solder is
260
C; solder at this temperature must not be in contact
with the joint for more than 5 seconds. The total contact
time of successive solder waves must not exceed
5 seconds.
The device may be mounted up to the seating plane, but
the temperature of the plastic body must not exceed the
specified maximum storage temperature (T
stg max
). If the
printed-circuit board has been pre-heated, forced cooling
may be necessary immediately after soldering to keep the
temperature within the permissible limit.
R
EPAIRING SOLDERED JOINTS
Apply a low voltage soldering iron (less than 24 V) to the
lead(s) of the package, below the seating plane or not
more than 2 mm above it. If the temperature of the
soldering iron bit is less than 300
C it may remain in
contact for up to 10 seconds. If the bit temperature is
between 300 and 400
C, contact may be up to 5 seconds.
SO, SSOP and TSSOP
R
EFLOW SOLDERING
Reflow soldering techniques are suitable for all SO, SSOP
and TSSOP packages.
Reflow soldering requires solder paste (a suspension of
fine solder particles, flux and binding agent) to be applied
to the printed-circuit board by screen printing, stencilling or
pressure-syringe dispensing before package placement.
Several techniques exist for reflowing; for example,
thermal conduction by heated belt. Dwell times vary
between 50 and 300 seconds depending on heating
method.
Typical reflow temperatures range from 215 to 250
C.
Preheating is necessary to dry the paste and evaporate
the binding agent. Preheating duration: 45 minutes at
45
C.
W
AVE SOLDERING
Wave soldering can be used for all SO packages. Wave
soldering is not recommended for SSOP and TSSOP
packages, because of the likelihood of solder bridging due
to closely-spaced leads and the possibility of incomplete
solder penetration in multi-lead devices.
If wave soldering is used - and cannot be avoided for
SSOP and TSSOP packages
- the following conditions
must be observed:
A double-wave (a turbulent wave with high upward
pressure followed by a smooth laminar wave) soldering
technique should be used.
The longitudinal axis of the package footprint must be
parallel to the solder flow and must incorporate solder
thieves at the downstream end.
Even with these conditions:
Only consider wave soldering SSOP packages that
have a body width of 4.4 mm, that is
SSOP16 (SOT369-1) or SSOP20 (SOT266-1).
Do not consider wave soldering TSSOP packages
with 48 leads or more, that is TSSOP48 (SOT362-1)
and TSSOP56 (SOT364-1).
During placement and before soldering, the package must
be fixed with a droplet of adhesive. The adhesive can be
applied by screen printing, pin transfer or syringe
dispensing. The package can be soldered after the
adhesive is cured.
Maximum permissible solder temperature is 260
C, and
maximum duration of package immersion in solder is
10 seconds, if cooled to less than 150
C within
6 seconds. Typical dwell time is 4 seconds at 250
C.
A mildly-activated flux will eliminate the need for removal
of corrosive residues in most applications.
R
EPAIRING SOLDERED JOINTS
Fix the component by first soldering two diagonally-
opposite end leads. Use only a low voltage soldering iron
(less than 24 V) applied to the flat part of the lead. Contact
time must be limited to 10 seconds at up to 300
C. When
using a dedicated tool, all other leads can be soldered in
one operation within 2 to 5 seconds between
270 and 320
C.
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1997 Nov 25
34
Philips Semiconductors
Product specification
Phase-locked-loop with VCO
74HC/HCT4046A
DEFINITIONS
LIFE SUPPORT APPLICATIONS
These products are not designed for use in life support appliances, devices, or systems where malfunction of these
products can reasonably be expected to result in personal injury. Philips customers using or selling these products for
use in such applications do so at their own risk and agree to fully indemnify Philips for any damages resulting from such
improper use or sale.
Data sheet status
Objective specification
This data sheet contains target or goal specifications for product development.
Preliminary specification
This data sheet contains preliminary data; supplementary data may be published later.
Product specification
This data sheet contains final product specifications.
Limiting values
Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one or
more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation
of the device at these or at any other conditions above those given in the Characteristics sections of the specification
is not implied. Exposure to limiting values for extended periods may affect device reliability.
Application information
Where application information is given, it is advisory and does not form part of the specification.