CA2077532C - Phase control circuit - Google Patents
Phase control circuit Download PDFInfo
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- CA2077532C CA2077532C CA002077532A CA2077532A CA2077532C CA 2077532 C CA2077532 C CA 2077532C CA 002077532 A CA002077532 A CA 002077532A CA 2077532 A CA2077532 A CA 2077532A CA 2077532 C CA2077532 C CA 2077532C
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- phase
- ranges
- signal
- control signal
- control
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Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
- H03L7/00—Automatic control of frequency or phase; Synchronisation
- H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
- H03L7/16—Indirect frequency synthesis, i.e. generating a desired one of a number of predetermined frequencies using a frequency- or phase-locked loop
- H03L7/18—Indirect frequency synthesis, i.e. generating a desired one of a number of predetermined frequencies using a frequency- or phase-locked loop using a frequency divider or counter in the loop
- H03L7/183—Indirect frequency synthesis, i.e. generating a desired one of a number of predetermined frequencies using a frequency- or phase-locked loop using a frequency divider or counter in the loop a time difference being used for locking the loop, the counter counting between fixed numbers or the frequency divider dividing by a fixed number
- H03L7/191—Indirect frequency synthesis, i.e. generating a desired one of a number of predetermined frequencies using a frequency- or phase-locked loop using a frequency divider or counter in the loop a time difference being used for locking the loop, the counter counting between fixed numbers or the frequency divider dividing by a fixed number using at least two different signals from the frequency divider or the counter for determining the time difference
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
- H03L7/00—Automatic control of frequency or phase; Synchronisation
- H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
- H03L7/08—Details of the phase-locked loop
- H03L7/10—Details of the phase-locked loop for assuring initial synchronisation or for broadening the capture range
- H03L7/107—Details of the phase-locked loop for assuring initial synchronisation or for broadening the capture range using a variable transfer function for the loop, e.g. low pass filter having a variable bandwidth
- H03L7/1075—Details of the phase-locked loop for assuring initial synchronisation or for broadening the capture range using a variable transfer function for the loop, e.g. low pass filter having a variable bandwidth by changing characteristics of the loop filter, e.g. changing the gain, changing the bandwidth
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
- H03L7/00—Automatic control of frequency or phase; Synchronisation
- H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
- H03L7/08—Details of the phase-locked loop
- H03L7/085—Details of the phase-locked loop concerning mainly the frequency- or phase-detection arrangement including the filtering or amplification of its output signal
- H03L7/089—Details of the phase-locked loop concerning mainly the frequency- or phase-detection arrangement including the filtering or amplification of its output signal the phase or frequency detector generating up-down pulses
- H03L7/0891—Details of the phase-locked loop concerning mainly the frequency- or phase-detection arrangement including the filtering or amplification of its output signal the phase or frequency detector generating up-down pulses the up-down pulses controlling source and sink current generators, e.g. a charge pump
- H03L7/0895—Details of the current generators
- H03L7/0898—Details of the current generators the source or sink current values being variable
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
- H03L7/00—Automatic control of frequency or phase; Synchronisation
- H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
- H03L7/08—Details of the phase-locked loop
- H03L7/085—Details of the phase-locked loop concerning mainly the frequency- or phase-detection arrangement including the filtering or amplification of its output signal
- H03L7/095—Details of the phase-locked loop concerning mainly the frequency- or phase-detection arrangement including the filtering or amplification of its output signal using a lock detector
Abstract
PLL control circuits in horizontal oscillators, when locked, must have a low control rate so that, for example, no jitter is generated by noisy input signals. Owing to the infavourable scanning ratio between the synchronising pulse length and the line duration (4.7:64), however, the control rate at greater phase differences in the PLL input signals is low and, e.g. when a television receiver is switched over between different programme sources, it takes a relatively long time (a few half-images) for the line synchronisation to become locked again. By logically assessing an additional pulse already available or easily generated in the television receiver, the control signal for the VCO in the PLL may be switched over at greater phase deviations, e.g. to a fourfold control current. For PLL control with input signals which do not have a pulse-duty factor ratio of 50:50.
Description
Wl lI l I bU3 Yt:'ll~Yyl/ ~U ICU
YIIaSe COI1tr01 C1~C111t '1'ne lnVentlOn relates t0 a phase control circuit.
~zate of zne arL
rresent day s television receivers use a rLL regulation ~pnase iocKed ioop~ for line synchronization in the horizontal oscillator. 'rhe norizoz~tai oscillator generates.a rhii signal having the zrequency oz the horizontal synchronization pulse ~H-~ync~, however, paving another scanning ratio.
lz, zor example, another programme source is switched on or a change oz station is executed then the line synchronization in the horizontal oscillator should happen as quicKiy as possible in order to, zor example, avoid a distorted image disturbing the viewer and to bring componentries in the television receiver controlled by the rhii signal quiciciy into a dezined state oz operation.
In order to ensure good regulating characteristics of the rLL in the iociced state the characteristic curve or the rLL
regulation should have certain properties, zor example, a larger regulation time icontroi rated constant, so that, zor example, noise superimposed upon the television signal genezates no fitter in the rLL regulating loop in spite oz the, in principle, temporal precision of the synchronizing poises.
wl. l I 1 % bU3 - l - YC;'1 I r;Yy 1l UU I5v in file uiliociced szaze, however, file YLL snouici lock qulCK.Ly. 'unis, as suctl, requires a small control rate CU115 L.dllL .
however, as the n-sync ~e.g. ~.~ usj is relatively short compared to the line duration ~e.g. b~ psj the regulating criaracteristics oz the YLL are non-linear scanning ratio oz the YLL input signals ~.i:o~j. vrnrougn this, over a wide phase range the control rate is independent oz the amount of phase deviation, and the YLL locks relatively slowly in case or iargers phase deviations, even when a time constant switcn-over to the vex mode t~ times raster] is carried out.
rig. i snows a known YLL regulation. what is sriown is a phase comparator ii which receives the n-sync and the Ynii signal as input signals. Wne output oz the phase comparator ii contains a current source ror the control current i~. ~rnis control current is low pass =iitered in the loop zilter l~ and led to a v~u i3 ~voitage controlled oscillator]. rne vw i3 contains a ~crequency divider and supplies at its output trie rriii signal at line frequency ~e.g. i~.bl5 nriZ). In the locked state n-Sync and Yhii signal are locked in phase.
x~ig. ~ snows the H-Sync, the Ynii signal and the control current i~ flout]. ~rrie iezt halt oz the zigure snows tire locked state. ~rne Ynii signal and the n-aync nave a phase shirt flcp oz fi~v~ or, respectively, -~u~, and the resulting average control current has trie value u. ~rhe right halt oz the figure shows a non-locked state. l.n large priase di=ierence ranges the amount oz the control current i~ is independent oz the phase position of the Yhii signal.
~rhis correlation is illustrated in rig. 3 tuninterrupted line]. only in relatively small phase dirierence ranges oz bcp ~approximateiy -iu3~ ... -ii°, ii~ ... iv3°j the average control current Lout changes as a function of the phase 2fl775 ~~
deviation of the Phil signal, i.e. a larger phase deviation causes a larger average control current Iout.
In the range of -77° .... 77° a relatively large phase deviation of the Phil signal leads to only a relatively small constant average control current Iout although it should become larger with larger phase deviation. Consequently, it takes relatively long for the PLL to regulate a larger phase deviation. This leads to the above mentioned disadvantages.
On the other hand, a general increase of the control current 14 leads to unfavorable regulating characteristics in the locked state in case of a noisy input signal. In addition, a general increase of the average control current which is too strong can cause the control loop to oscillate.
Invention The invention is based on the object of enabling, even in the case of a larger phase deviation between H-Sync and Phil signal, a fast locking of the PLL without changing the regulating characteristic curve of the PLL in the locked state.
According to a broad aspect, the invention provides a phase control circuit for at least two logic signals of the same frequency, wherein at least one of the two signals has a mark-space ratio differing from a mark-space ratio of 50:50, where the phase position of the signals in relation to one another can be controlled by a control signal and where the control signal changes in linear fashion in the two ranges of small phase differences which extend symmetrically around the phase positions of in each case +90° and -90° and between ,w20775 these two ranges and outside of these two ranges has a component which remains constant in terms of amplitude and which possesses a first amplitude, characterised in that: with the aid of a further logic signal, the frequency of which is identical to the frequency of the two logic signals and the pulse breadth of which is distinctly greater than that of the logic signal with the differing mark-space ratio, the source for the control signal is switched over by switching means, which are controlled by a lock detector, in such manner that between these two ranges and outside of these two ranges the control signal has a component which remains constant in terms of amplitude and which possesses a second amplitude increased by a specified factor; the source is switched over to the increased control signal when the logic signal with the differing mark-space ratio and the further logic signal are not coupled in phase-locked fashion; the source is switched over to the normal control signal when the phase of the logic signal with the differing mark-space ratio falls within the pulse duration of the further logic signal; where the sections of the linear components of the control signal, which in the ranges of small phase differences extend symmetrically around the phase positions of in each case +90° and -90°, are correspondingly enlarged.
Ideal would be a characteristic curve such as represented in Fig. 3 by the dotted line and such as is always present with conventional PLL circuits (scanning ratio of the input signals 1:1). The control current for the VCO is increased in an extended phase deviation range (in the non-- 3a -linear part of the PLL regulation characteristic curve) by a certain factor. To do this., a line-synchronous LRI pulse (line retrace inhibit) available in many present-day television receivers is - 3b -W~ 17 1 I bD3 - ~k - Yl:'T! riP'j ll vU I ~v ~d7~~3~
used which has a prolonged pulse duration compared to the n-sync and, For example, suppresses interference signals during the non-visible part or the fines. instead of the Lrti pulse it is also possible to use any other line-synchronous pulse which has a prolonged pulse duration compared to the H-sync.
vrawinQs In the following, an emboaiment example of the invention is illustrated by means of drawings. ~rnese snow in:
rig. i YLL circuit in a horizontal oscillator IKnownj, rig. z time diagram oz input and output signals oz the phase comparator in the YLL ~icnown~, rig. 3 characteristic curve for the average output current or the phase comparator as a function oz the phase difrerence oz the input signals ~icnownj, r-ig. ~ YL.u circuit according to the invention ~n a horizontal oscillator, rig. ~ time diagram oz input and output signals or the phase comparator in tine YLL circuit according to the invention, rig. b characteristic curve according to the invention for the average output current of the phase comparator as a function oz the phase difference oz the input signals.
rigs. i through 3 nave already peen described above.
w _~iii~tiv3 - ~ -~.m~odiment examples rig. ~ snows a phase comparator ~i which receives the H-~ync, the ~nii signal and an LHl signal as input signal. ~W a output of the phase comparator ~i contains a controllable current source for tine control current gig. ~rnis control current is low pass filtered in the loop filter ~i anti fed to a vi:u ~3. ~rne vi:u ~3 supplies at its output, for example, a ~vu xHZ signal. in a downstream logic and frequency divider circuit ~i, for example, the Lxl signal is generated and the Ynii signal with line frequency ~e.g. i5.bl~ nnZ~. lne LK1 signal is, as mentioned above, already available in many television receivers. otherwise, it is easy for an expert in the art to derive it fxom other signals in the television device. ~rnis can ire carried out by means or scanning counter states in tine frequency divider circuit.
ii no H-Sync is present, =or example, with reproduction oz teletext gages stored in the television device a=ter the closing down of transmission, switching-over to a nixed control current ~n occurs by means of switch 45. ~rne information required nerefor ono H-Sync presents is generated in the h-Sync recognition circuit ~
~n reproduction oz a video recorder signal, for example, the control current in the controllable current source in the pi~ase cornparator 4i may be increased by the =actor three so that wow and flutter oz the video recorder or fields reproduced with aif~erent length ~approximateiy +i- i use can be better regulated ;aeviat~an controlled). ~rne information concerning tire video recorder operation can be supplied, ror example, ~TOm a bL:Attl: 50CK2L LO Llle phase compar azor 4 i .
Now, a iocic detector ~v which receives the H-sync and tire Ynii signal as input signals aetermines whether tine YLL has W~ j l I 1 ) b133 - b - YC:'1 l r;Y'j l I vU l 5il _ ~(~,~,~~~~
iocices. in the iocices state H-Sync and Yhii signal are phase iocices and the switch ~~ is open. In the uniocices state switch ~~ is closed and the control current is increased in the control source by a factor, for example, tour. 'This enables the YLL to regulate a phase deviation of the Yhii signal from the H-Sync more quicxly.
rig. ~ shows the H-sync 53, r~, the rhii signal 5i, the ~xl signal ~z and the control current 5~, ~b your). ~rhe upper part oz the figure shows the iocKed state. ~rhe Yhii signal ~i and the ri-5ync 53 have a phase shift fl~ oz -ryu~ or, respectively, -yv~, and the resulting average control current Iout has the value 0 (+IO and -IO averaged).
~rine lower part oz the figure shows a non-iocices state.
vuring the interval of the H-Sync 5~, which lies outsise the duration or the Lxl pulse ~z, the control current ~b your) is increased by the factor four. if, however, the phase oz the h-sync 55 Ties within the suration of the LHi pulse 5z, the the control current ~a remains unchanged.
r~rom tine above described follows the characteristic curve shown in rig. n for the control current ~~, 5~, 5o your) as a function of the phase deviation ~cp. in the ranges -iu3~ ...
-i~~ aria ~i~ ... iv~~ this characteristic curve is identical with that from rig. 3. In the ranges of approximately c -iiu=, -30= ... i0~ and ~ ii0=, however, tine control current ~~, 5~, ~b is advantageously increased icy the factor ~ with respect to the characteristic curve in rig. 3. in the operation with video recorder the control current can then be increases icy the factor il (~~~).
tzy virtue of the enlarged linear characteristic curve range (-flay ... -iv~, ~v= ... iiu°) the YLL regulation attains almost ideal characteristics ~ciotted lines), i.e. in the iocices state the regulating characteristic is slow and the vi j1I .L IbU3 - ~ - YL'll~YyllUV 73U
regulating characteristic becomes raster witn increasing pnase aiizerence. ~rhe regulating characteristic in the still remaining non-linear part ~~ -iiu~, -iu~ ... iuV, ~ iiu~j is advantageously improved by the elevations at -iiv=, -iu~, ~v~
and i i u= .
The average control current Iout which is formed from the r.nn+r~l m,rrcn~ dd ! Tnns+- 1 her i-he fi 1 Lori nrr i t~ ~hc l nnn f=l ~cr ____ _ - _ ~ _ _~ 1 __. _- _____~ ___ _.
~z can also De changed in its amount correspondingly in tnat the loop zilter gi is modified in its transzer function wnereDy, then, the current source in the pnase comparator outputs a steady current iou-~.
~rrie invention is suitable for application not only for YLL
regulations in horizontal oscillator circuits put generally in YLL regulations with signals which do not nave trie ideal pulse-duty zactor ratio oz ~u:~v.
YIIaSe COI1tr01 C1~C111t '1'ne lnVentlOn relates t0 a phase control circuit.
~zate of zne arL
rresent day s television receivers use a rLL regulation ~pnase iocKed ioop~ for line synchronization in the horizontal oscillator. 'rhe norizoz~tai oscillator generates.a rhii signal having the zrequency oz the horizontal synchronization pulse ~H-~ync~, however, paving another scanning ratio.
lz, zor example, another programme source is switched on or a change oz station is executed then the line synchronization in the horizontal oscillator should happen as quicKiy as possible in order to, zor example, avoid a distorted image disturbing the viewer and to bring componentries in the television receiver controlled by the rhii signal quiciciy into a dezined state oz operation.
In order to ensure good regulating characteristics of the rLL in the iociced state the characteristic curve or the rLL
regulation should have certain properties, zor example, a larger regulation time icontroi rated constant, so that, zor example, noise superimposed upon the television signal genezates no fitter in the rLL regulating loop in spite oz the, in principle, temporal precision of the synchronizing poises.
wl. l I 1 % bU3 - l - YC;'1 I r;Yy 1l UU I5v in file uiliociced szaze, however, file YLL snouici lock qulCK.Ly. 'unis, as suctl, requires a small control rate CU115 L.dllL .
however, as the n-sync ~e.g. ~.~ usj is relatively short compared to the line duration ~e.g. b~ psj the regulating criaracteristics oz the YLL are non-linear scanning ratio oz the YLL input signals ~.i:o~j. vrnrougn this, over a wide phase range the control rate is independent oz the amount of phase deviation, and the YLL locks relatively slowly in case or iargers phase deviations, even when a time constant switcn-over to the vex mode t~ times raster] is carried out.
rig. i snows a known YLL regulation. what is sriown is a phase comparator ii which receives the n-sync and the Ynii signal as input signals. Wne output oz the phase comparator ii contains a current source ror the control current i~. ~rnis control current is low pass =iitered in the loop zilter l~ and led to a v~u i3 ~voitage controlled oscillator]. rne vw i3 contains a ~crequency divider and supplies at its output trie rriii signal at line frequency ~e.g. i~.bl5 nriZ). In the locked state n-Sync and Yhii signal are locked in phase.
x~ig. ~ snows the H-Sync, the Ynii signal and the control current i~ flout]. ~rrie iezt halt oz the zigure snows tire locked state. ~rne Ynii signal and the n-aync nave a phase shirt flcp oz fi~v~ or, respectively, -~u~, and the resulting average control current has trie value u. ~rhe right halt oz the figure shows a non-locked state. l.n large priase di=ierence ranges the amount oz the control current i~ is independent oz the phase position of the Yhii signal.
~rhis correlation is illustrated in rig. 3 tuninterrupted line]. only in relatively small phase dirierence ranges oz bcp ~approximateiy -iu3~ ... -ii°, ii~ ... iv3°j the average control current Lout changes as a function of the phase 2fl775 ~~
deviation of the Phil signal, i.e. a larger phase deviation causes a larger average control current Iout.
In the range of -77° .... 77° a relatively large phase deviation of the Phil signal leads to only a relatively small constant average control current Iout although it should become larger with larger phase deviation. Consequently, it takes relatively long for the PLL to regulate a larger phase deviation. This leads to the above mentioned disadvantages.
On the other hand, a general increase of the control current 14 leads to unfavorable regulating characteristics in the locked state in case of a noisy input signal. In addition, a general increase of the average control current which is too strong can cause the control loop to oscillate.
Invention The invention is based on the object of enabling, even in the case of a larger phase deviation between H-Sync and Phil signal, a fast locking of the PLL without changing the regulating characteristic curve of the PLL in the locked state.
According to a broad aspect, the invention provides a phase control circuit for at least two logic signals of the same frequency, wherein at least one of the two signals has a mark-space ratio differing from a mark-space ratio of 50:50, where the phase position of the signals in relation to one another can be controlled by a control signal and where the control signal changes in linear fashion in the two ranges of small phase differences which extend symmetrically around the phase positions of in each case +90° and -90° and between ,w20775 these two ranges and outside of these two ranges has a component which remains constant in terms of amplitude and which possesses a first amplitude, characterised in that: with the aid of a further logic signal, the frequency of which is identical to the frequency of the two logic signals and the pulse breadth of which is distinctly greater than that of the logic signal with the differing mark-space ratio, the source for the control signal is switched over by switching means, which are controlled by a lock detector, in such manner that between these two ranges and outside of these two ranges the control signal has a component which remains constant in terms of amplitude and which possesses a second amplitude increased by a specified factor; the source is switched over to the increased control signal when the logic signal with the differing mark-space ratio and the further logic signal are not coupled in phase-locked fashion; the source is switched over to the normal control signal when the phase of the logic signal with the differing mark-space ratio falls within the pulse duration of the further logic signal; where the sections of the linear components of the control signal, which in the ranges of small phase differences extend symmetrically around the phase positions of in each case +90° and -90°, are correspondingly enlarged.
Ideal would be a characteristic curve such as represented in Fig. 3 by the dotted line and such as is always present with conventional PLL circuits (scanning ratio of the input signals 1:1). The control current for the VCO is increased in an extended phase deviation range (in the non-- 3a -linear part of the PLL regulation characteristic curve) by a certain factor. To do this., a line-synchronous LRI pulse (line retrace inhibit) available in many present-day television receivers is - 3b -W~ 17 1 I bD3 - ~k - Yl:'T! riP'j ll vU I ~v ~d7~~3~
used which has a prolonged pulse duration compared to the n-sync and, For example, suppresses interference signals during the non-visible part or the fines. instead of the Lrti pulse it is also possible to use any other line-synchronous pulse which has a prolonged pulse duration compared to the H-sync.
vrawinQs In the following, an emboaiment example of the invention is illustrated by means of drawings. ~rnese snow in:
rig. i YLL circuit in a horizontal oscillator IKnownj, rig. z time diagram oz input and output signals oz the phase comparator in the YLL ~icnown~, rig. 3 characteristic curve for the average output current or the phase comparator as a function oz the phase difrerence oz the input signals ~icnownj, r-ig. ~ YL.u circuit according to the invention ~n a horizontal oscillator, rig. ~ time diagram oz input and output signals or the phase comparator in tine YLL circuit according to the invention, rig. b characteristic curve according to the invention for the average output current of the phase comparator as a function oz the phase difference oz the input signals.
rigs. i through 3 nave already peen described above.
w _~iii~tiv3 - ~ -~.m~odiment examples rig. ~ snows a phase comparator ~i which receives the H-~ync, the ~nii signal and an LHl signal as input signal. ~W a output of the phase comparator ~i contains a controllable current source for tine control current gig. ~rnis control current is low pass filtered in the loop filter ~i anti fed to a vi:u ~3. ~rne vi:u ~3 supplies at its output, for example, a ~vu xHZ signal. in a downstream logic and frequency divider circuit ~i, for example, the Lxl signal is generated and the Ynii signal with line frequency ~e.g. i5.bl~ nnZ~. lne LK1 signal is, as mentioned above, already available in many television receivers. otherwise, it is easy for an expert in the art to derive it fxom other signals in the television device. ~rnis can ire carried out by means or scanning counter states in tine frequency divider circuit.
ii no H-Sync is present, =or example, with reproduction oz teletext gages stored in the television device a=ter the closing down of transmission, switching-over to a nixed control current ~n occurs by means of switch 45. ~rne information required nerefor ono H-Sync presents is generated in the h-Sync recognition circuit ~
~n reproduction oz a video recorder signal, for example, the control current in the controllable current source in the pi~ase cornparator 4i may be increased by the =actor three so that wow and flutter oz the video recorder or fields reproduced with aif~erent length ~approximateiy +i- i use can be better regulated ;aeviat~an controlled). ~rne information concerning tire video recorder operation can be supplied, ror example, ~TOm a bL:Attl: 50CK2L LO Llle phase compar azor 4 i .
Now, a iocic detector ~v which receives the H-sync and tire Ynii signal as input signals aetermines whether tine YLL has W~ j l I 1 ) b133 - b - YC:'1 l r;Y'j l I vU l 5il _ ~(~,~,~~~~
iocices. in the iocices state H-Sync and Yhii signal are phase iocices and the switch ~~ is open. In the uniocices state switch ~~ is closed and the control current is increased in the control source by a factor, for example, tour. 'This enables the YLL to regulate a phase deviation of the Yhii signal from the H-Sync more quicxly.
rig. ~ shows the H-sync 53, r~, the rhii signal 5i, the ~xl signal ~z and the control current 5~, ~b your). ~rhe upper part oz the figure shows the iocKed state. ~rhe Yhii signal ~i and the ri-5ync 53 have a phase shift fl~ oz -ryu~ or, respectively, -yv~, and the resulting average control current Iout has the value 0 (+IO and -IO averaged).
~rine lower part oz the figure shows a non-iocices state.
vuring the interval of the H-Sync 5~, which lies outsise the duration or the Lxl pulse ~z, the control current ~b your) is increased by the factor four. if, however, the phase oz the h-sync 55 Ties within the suration of the LHi pulse 5z, the the control current ~a remains unchanged.
r~rom tine above described follows the characteristic curve shown in rig. n for the control current ~~, 5~, 5o your) as a function of the phase deviation ~cp. in the ranges -iu3~ ...
-i~~ aria ~i~ ... iv~~ this characteristic curve is identical with that from rig. 3. In the ranges of approximately c -iiu=, -30= ... i0~ and ~ ii0=, however, tine control current ~~, 5~, ~b is advantageously increased icy the factor ~ with respect to the characteristic curve in rig. 3. in the operation with video recorder the control current can then be increases icy the factor il (~~~).
tzy virtue of the enlarged linear characteristic curve range (-flay ... -iv~, ~v= ... iiu°) the YLL regulation attains almost ideal characteristics ~ciotted lines), i.e. in the iocices state the regulating characteristic is slow and the vi j1I .L IbU3 - ~ - YL'll~YyllUV 73U
regulating characteristic becomes raster witn increasing pnase aiizerence. ~rhe regulating characteristic in the still remaining non-linear part ~~ -iiu~, -iu~ ... iuV, ~ iiu~j is advantageously improved by the elevations at -iiv=, -iu~, ~v~
and i i u= .
The average control current Iout which is formed from the r.nn+r~l m,rrcn~ dd ! Tnns+- 1 her i-he fi 1 Lori nrr i t~ ~hc l nnn f=l ~cr ____ _ - _ ~ _ _~ 1 __. _- _____~ ___ _.
~z can also De changed in its amount correspondingly in tnat the loop zilter gi is modified in its transzer function wnereDy, then, the current source in the pnase comparator outputs a steady current iou-~.
~rrie invention is suitable for application not only for YLL
regulations in horizontal oscillator circuits put generally in YLL regulations with signals which do not nave trie ideal pulse-duty zactor ratio oz ~u:~v.
Claims (4)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A phase control circuit for at least two logic signals of the same frequency, wherein at least one of the two signals has a mark-space ratio differing from a mark-space ratio of 50:50, where the phase position of the signals in relation to one another can be controlled by a control signal and where the control signal changes in linear fashion in the two ranges of small phase differences which extend symmetrically around the phase positions of in each case +90°
and -90° and between these two ranges and outside of these two ranges has a component which remains constant in terms of amplitude and which possesses a first amplitude, characterised in that:
with the aid of a further logic signal, the frequency of which is identical to the frequency of the two logic signals and the pulse breadth of which is distinctly greater than that of the logic signal with the differing mark-space ratio, the source for the control signal is switched over by switching means, which are controlled by a lock detector, in such manner that between these two ranges and outside of these two ranges the control signal has a component which remains constant in terms of amplitude and which possesses a second amplitude increased by a specified factor;
the source is switched over to the increased control signal when the logic signal with the differing mark-space ratio and the further logic signal are not coupled in phase-locked fashion;
the source is switched over to the normal control signal when the phase of the logic signal with the differing mark-space ratio falls within the pulse duration of the further logic signal;
where the sections of the linear components of the control signal, which in the ranges of small phase differences extend symmetrically around the phase positions of in each case +90° and -90°, are correspondingly enlarged.
and -90° and between these two ranges and outside of these two ranges has a component which remains constant in terms of amplitude and which possesses a first amplitude, characterised in that:
with the aid of a further logic signal, the frequency of which is identical to the frequency of the two logic signals and the pulse breadth of which is distinctly greater than that of the logic signal with the differing mark-space ratio, the source for the control signal is switched over by switching means, which are controlled by a lock detector, in such manner that between these two ranges and outside of these two ranges the control signal has a component which remains constant in terms of amplitude and which possesses a second amplitude increased by a specified factor;
the source is switched over to the increased control signal when the logic signal with the differing mark-space ratio and the further logic signal are not coupled in phase-locked fashion;
the source is switched over to the normal control signal when the phase of the logic signal with the differing mark-space ratio falls within the pulse duration of the further logic signal;
where the sections of the linear components of the control signal, which in the ranges of small phase differences extend symmetrically around the phase positions of in each case +90° and -90°, are correspondingly enlarged.
2. A phase control circuit as claimed in claim 1, characterised in that the ranges of small phase differences between the two logic signals occur at approximately -103° ...
-77° and 77° ... 103°, and that the enlargement of these ranges comprises phase differences of approximately -110° ...
-103°, -77° ... -70°, 70° ... 77° and 103° ... 110°.
-77° and 77° ... 103°, and that the enlargement of these ranges comprises phase differences of approximately -110° ...
-103°, -77° ... -70°, 70° ... 77° and 103° ... 110°.
3. A phase control circuit as claimed in claim 1 or 2, characterised in that the curve for the control signal exhibits a greater slope in the enlarged linear ranges than in the ranges of small phase differences.
4. A phase control circuit as claimed in any one of claims 1 to 3, characterised in that the control signal is a control current.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP4013694.9 | 1990-04-28 | ||
| DE4013694A DE4013694A1 (en) | 1990-04-28 | 1990-04-28 | PHASE CONTROL |
| PCT/EP1991/000750 WO1991017603A1 (en) | 1990-04-28 | 1991-04-19 | Phase control circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2077532A1 CA2077532A1 (en) | 1991-10-29 |
| CA2077532C true CA2077532C (en) | 2000-10-17 |
Family
ID=6405332
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002077532A Expired - Fee Related CA2077532C (en) | 1990-04-28 | 1991-04-19 | Phase control circuit |
Country Status (12)
| Country | Link |
|---|---|
| US (1) | US5334954A (en) |
| EP (1) | EP0527167B1 (en) |
| JP (1) | JP3119868B2 (en) |
| KR (1) | KR100215766B1 (en) |
| AU (1) | AU7745191A (en) |
| CA (1) | CA2077532C (en) |
| DE (2) | DE4013694A1 (en) |
| ES (1) | ES2059136T3 (en) |
| HK (1) | HK68895A (en) |
| HU (1) | HU220468B1 (en) |
| SG (1) | SG30581G (en) |
| WO (1) | WO1991017603A1 (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5574407A (en) * | 1993-04-20 | 1996-11-12 | Rca Thomson Licensing Corporation | Phase lock loop with error consistency detector |
| DE69533913T2 (en) * | 1994-05-26 | 2005-05-25 | Matsushita Electric Industrial Co., Ltd., Kadoma | frequency synthesizer |
| US5534826A (en) * | 1994-10-24 | 1996-07-09 | At&T Corp. | Oscillator with increased reliability start up |
| CA2263221C (en) * | 1996-08-13 | 2002-05-28 | Masanori Kurita | Pll circuit for digital display apparatus |
| JPH10257041A (en) * | 1997-03-11 | 1998-09-25 | Sony Corp | Phase locked loop circuit and reproducing device |
| JP2000232355A (en) * | 1999-02-09 | 2000-08-22 | Mitsubishi Electric Corp | Phase locked loop circuit |
| JP4407031B2 (en) * | 2000-09-21 | 2010-02-03 | ソニー株式会社 | Phase-locked loop circuit and delay-locked loop circuit |
| WO2006030724A1 (en) * | 2004-09-17 | 2006-03-23 | Asahi Kasei Chemicals Corporation | Method for separating by-product alcohols on commercial scale |
| US20080045755A1 (en) * | 2004-09-21 | 2008-02-21 | Shinsuke Fukuoka | Industrial Process For Separating Out By-Produced Alcohol |
| JP4292214B2 (en) * | 2004-10-14 | 2009-07-08 | 旭化成ケミカルズ株式会社 | Method for producing high-purity diaryl carbonate |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL169811C (en) * | 1975-10-03 | 1982-08-16 | Philips Nv | IMAGE CONTROL SYNCHRONIZATION CIRCUIT AND TV RECEIVER. |
| US4156855A (en) * | 1978-01-26 | 1979-05-29 | Rca Corporation | Phase-locked loop with variable gain and bandwidth |
| CA1238409A (en) * | 1983-09-21 | 1988-06-21 | Akihiro Kikuchi | Apparatus for controlling the frequency of a voltage controlled oscillator |
| DE3715929A1 (en) * | 1987-05-13 | 1988-11-24 | Thomson Brandt Gmbh | CIRCUIT FOR THE AUTOMATIC SWITCHING OF THE CONTROL SPEED OF A PHASE CONTROL CIRCUIT |
| DE3887266T2 (en) * | 1987-10-26 | 1994-07-21 | Philips Nv | Horizontal synchronous circuit. |
-
1990
- 1990-04-28 DE DE4013694A patent/DE4013694A1/en not_active Withdrawn
-
1991
- 1991-04-19 WO PCT/EP1991/000750 patent/WO1991017603A1/en active IP Right Grant
- 1991-04-19 JP JP03507927A patent/JP3119868B2/en not_active Expired - Fee Related
- 1991-04-19 DE DE59102513T patent/DE59102513D1/en not_active Expired - Fee Related
- 1991-04-19 ES ES91908354T patent/ES2059136T3/en not_active Expired - Lifetime
- 1991-04-19 EP EP91908354A patent/EP0527167B1/en not_active Expired - Lifetime
- 1991-04-19 CA CA002077532A patent/CA2077532C/en not_active Expired - Fee Related
- 1991-04-19 HU HU9202776A patent/HU220468B1/en not_active IP Right Cessation
- 1991-04-19 SG SG1995904801A patent/SG30581G/en unknown
- 1991-04-19 KR KR1019920702596A patent/KR100215766B1/en not_active IP Right Cessation
- 1991-04-19 AU AU77451/91A patent/AU7745191A/en not_active Abandoned
-
1992
- 1992-11-25 US US07/980,946 patent/US5334954A/en not_active Expired - Lifetime
-
1995
- 1995-05-04 HK HK68895A patent/HK68895A/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| HK68895A (en) | 1995-05-12 |
| HU9202776D0 (en) | 1992-12-28 |
| HUT64434A (en) | 1993-12-28 |
| HU220468B1 (en) | 2002-02-28 |
| DE4013694A1 (en) | 1991-10-31 |
| WO1991017603A1 (en) | 1991-11-14 |
| JPH05507184A (en) | 1993-10-14 |
| DE59102513D1 (en) | 1994-09-15 |
| JP3119868B2 (en) | 2000-12-25 |
| EP0527167B1 (en) | 1994-08-10 |
| AU7745191A (en) | 1991-11-27 |
| ES2059136T3 (en) | 1994-11-01 |
| KR100215766B1 (en) | 1999-08-16 |
| EP0527167A1 (en) | 1993-02-17 |
| SG30581G (en) | 1995-09-01 |
| US5334954A (en) | 1994-08-02 |
| CA2077532A1 (en) | 1991-10-29 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |