i

Apparatus for and method of producing proof prints

An apparatus for producing proof prints on which the correctness of page impositions can be checked comprises a stand configured to receive a roll of paper. A first printer and a second printer are provided for printing pages on the front side and the rear side, respectively, of a paper web fed from the paper roll. An optical sensor is arranged between the first printer and the second printer. The optical sensor is configured to detect the position of an alignment mark which has been printed by the first printer on the front side of the paper. A control unit modifies the spatial relationship between the rear side of the paper and what is printed on the rear side of the paper depending on the detected position of the alignment mark. This can be accomplished either by electronically modifying the second pages as such, or by mechanically modifying the paper position with respect to a printing head contained in the second printer.




i

Reflection densitometer

A method for determining optical density is disclosed. A first measurement is taken on a white area of a substrate (402). A second measurement is taken on an area of the substrate printed with ink (404). A relative optical density of the ink is determined using the first and second measurements (406).




i

Marking and/or scanning head, apparatus, and method

The invention relates to a marking and/or scanning head comprising a plurality of receiving spaces in which individual marking and/or sensing devices can be arranged for marking and/or scanning an object, wherein the receiving spaces are arranged in at least two sub-arrays, wherein at least one sub-array is movable and/or rotatable with regard to at least one other sub-array. The invention further relates to a marking and/or scanning apparatus and a method for operating a marking and/or scanning head or apparatus.




i

Method and device for controlling the register settings of a printing press

A method for controlling register settings of a printing press, includes rotating imaging cylinders of a first print unit and a second print unit, located downstream of the first print unit in a movement direction of a print medium, at a rotational speed to print an image on the print medium. The method includes of changing a length of the print image to a pre-determined length. The method further includes changing a register setting of the imaging cylinder of the second print unit based on the predetermined change in length of the print image to avoid misalignment of the print image printed by the first and the second print units on the print medium. Changing the register setting is dependent on a length of a section of the print medium between the first and the second print units. A device for controlling register settings of a printing press is also disclosed.




i

Digital sheet-fed printing method

A digital sheet-fed printing method includes providing one cycle of printing to print on a series of sheets of paper whose number is equal to the least common multiple of respective numbers of allocated positions; producing a reference signal on the basis of which an image in each color is printed on the sheet of paper; detecting with an image detection sensor means a mutual out of register between images in different colors printed on each sheet of paper in the series, furnishing the printing control means with a detection signal for each sheet of paper from the image detection sensor, and correcting the timing at which each image is printed on each sheet of paper in one cycle of printing so that timings to print the images in different colors on each sheet of paper coincide with one another; and printing images in the different colors.




i

Method of printing an image on a gelatin capsule

A paintball or other gelatin capsule has a printed image applied to its shell before encapsulation using a gelatin ribbon printing machine. The printing machine includes a motor driven cylindrical casting drum, a cylindrical print roll having a pattern formed on and around its outer periphery, said print roll being positioned relative to said casting drum so that said gelatin ribbon is sandwiched in between and in contact with both said casting drum and said print roll and so that the print roll is rotary driven by said casting drum solely through frictional contact with the gelatin ribbon. A rotary ink roller is in contact with the print roll to drives the ink roller solely through frictional contact between said print roll the inking roller. A doctor blade is configured to scrape excess ink from said inking roller. A method of printing on a gelatin capsule is also provided.




i

Operation of a cold foil apparatus by a printing press

A method of transferring a transfer foil having an image forming layer through a transfer gap of a printing press under a foil cycle timing control that is selectively changeable such that it can be turned on, turned off, or is adjustable in its frequency and period of operation as a function of operating parameters of the press.




i

Screen printer and method for detecting amount of residual paste

A light receiving section 27b receives a measurement beam, which is cast from a light projection section 27a and partially blocked by cream solder 19 scraped up by a squeegee 16, whereby a sensor 27 measures a one-dimensional size of a predetermined region of a cross sectional profile of the cream solder 19 as a cross sectional paste length and takes the cross sectional paste length as an index for an amount of residual cream solder 19. The amount of residual cream solder 19 can be numerically grasped at all times, so that versatility and accuracy in detecting the amount of residual cream solder 19 can be assured.




i

Printers, methods, and apparatus to filter imaging oil

Printers, methods, and apparatus to filter imaging oil are disclosed. An example apparatus to filter imaging oil, includes adjacent electrodes and a switching circuit. The example switching circuit selectively generates an electrostatic field between the adjacent electrodes to cause particles suspended in the imaging oil between the adjacent electrodes to adhere to at least one of the adjacent electrodes, and generates an alternating electric field between the adjacent electrodes to cause the particles to be detached from the adjacent electrodes.




i

Optimization of UV curing

A system and method of preparing a flexoplate so it is suitable for the printing of high resolution patterns. The method includes controlling the curing conditions of the flexoplate, thereby controlling the properties of said flexoplate such as floor thickness, pattern cross-sectional geometry, repeatability of printed features during the printing process, and durability of the flexoplate during the printing process.




i

Method and apparatus to position and align pre-punched printing plates on an imaging cylinder

An apparatus and method for positioning and aligning one or more pre-punched printing plates on a cylinder for imaging a plate in a computer-to-plate drum imaging device. The apparatus includes an imaging cylinder and a registration device connectable to the cylinder. The apparatus includes at least one groove and one pair of register pins, with a first register pin in a fixed position, and a second register pin movable in the groove to a second position, and collinear with the first register pin in the axial direction of the cylinder, arranged such that when connected to the cylinder, the registration device allows a plurality of pre-punched printing plates with variable widths to be positioned and aligned on the cylinder with simplicity.




i

Web coating applicator with cooling and material recovery

Apparatus and method for applying a water-based emulsion of silicone fluid to a printed web required to be cooled, such that evaporative cooling of the web is promoted in addition to coating of said web with a silicone material. Water evaporated following the application of the silicone fluid to the web is recovered by condensation on the applicator(s) and reapplied to the web, thus economizing the amount of silicone fluid mixture necessary to provide both cooling and enhanced slip characteristics necessary for further handling and processing of the web. The condensation step is effected by containing the evaporated water from the web within a compact enclosure enveloping both the applicator(s) and the web, and optionally chilling said applicator(s) with a cooling medium, preferably water, by means of said cooling medium flowing through at least one of the applicators. In certain embodiments, in addition to condensing the evaporated water, the airborne silicone mist created in the coating step is captured and is returned to the fluid applicator.




i

High speed printing ink

Formulations for solvent-based flexographic or rotogravure inks, which are capable high-quality, defect-free printing at high speeds, contain flexographic ink resins solutions and solvent mixtures which are designed to maintain a dynamic solubility parameter in the ink as the dry state is approached during the printing process. The inks described show extremely high quality printing at linear press speeds above 1800 fee per minute (ca 0.549 km/min).




i

Systems for dampening fluid removal, vapor control and recovery for ink-based digital printing

A system for dampening fluid recovery in an ink-based digital printing system includes a seal manifold having a front seal portion, the front seal portion having an upper wall facing the imaging surface, the upper wall being configured to define an air flow channel with the imaging surface, the upper wall being contoured to form a distance between the upper wall and the imaging surface at an evaporation location that is less than distance between the upper wall and the imaging surface at locations interposing the evaporation location and a vacuum inlet channel of the seal manifold.




i

Hybrid image format

Hybrid image format techniques are described in which multiple resolution images are concatenated to a standard bitmap image to create a hybrid image file. The hybrid image file is created through combining a relatively low resolution image with the additional images in a multi-frame format having higher resolution. The hybrid image file may contain data detectable to signal that higher resolution images are available in the hybrid image file. A hybrid aware application may be configured to detect and output a higher resolution image from the hybrid image file based on detection of the data. A legacy application that is not configured to detect the data may be unaware of higher resolution images contained in the hybrid image file, and accordingly outputs the relatively low resolution image.




i

Method and an apparatus for processing a lenticular printing substrate

A method for preparing a lenticular guide roll for use in a lenticular printing run. The method comprises providing a printing roll of a printing press and a first piece of lenticular media. The first piece of lenticular printing substrate has a pitch which is substantially identical to a second lenticular printing substrate to be used in the lenticular printing run. The, method further comprises attaching the first piece of lenticular printing substrate to the printing roll to allow the maneuvering of the second lenticular printing substrate by the printing roll in the printing press.




i

Environmental control subsystem for a variable data lithographic apparatus

Methods and structures are disclosed to minimize the presence of vapor clouding in the path between an energy (e.g., radiation) source and the dampening fluid layer in a variable data lithography system. Also disclosed are conditions for optimizing vaporization of regions of the dampening fluid layer for a given laser source power. Conditions are also disclosed for minimizing re-condensation of vaporized dampening fluid onto the patterned dampening fluid layer. Accordingly, a reduction in the power required for, and an increase in the reproducibility of, patterning of a dampening fluid layer over a reimageable surface in a variable data lithography system are disclosed.




i

Dampening fluid recovery in a variable data lithography system

In a variable data lithography system that employs a patterned dampening fluid layer for image formation, dampening fluid may be removed prior to image transfer to a substrate. Removed dampening fluid may be recovered and recycled to reduce operating expenses and environmental waste. A replacement fluid may be applied after inking and after removal of the dampening fluid. The replacement fluid preferentially occupies the regions previously occupied by dampening fluid, and may lubricate the transfer nip. Any replacement fluid and ink not transferred to the substrate upon printing may then be cleaned from the print image carrier prior to forming a new dampening fluid layer and subsequent pattern formation.




i

Printer cylinder assembly for a printing machine

A printing cylinder assembly for a printing machine having a sleeve cylinder which can be simply coupled to and decoupled from a rotating shaft and which can be exchanged easily. The sleeve cylinder is mounted to fit on the rotating shaft so that it can be fitted on, and be extracted from, the rotating shaft, constituting a printing cylinder. The rotating shaft is provided with a cam shaft and a coupling member that constitutes a coupling mechanism. In a coupling and a decoupling state which the coupling mechanism comes into, rotations of the cam shaft cause the coupling member to couple and decouple the sleeve cylinder to and from the rotating shaft when the coupling member is diametrically urged against, and parted from, the inner diametric surface of the sleeve cylinder, respectively.




i

Forming an image on a flexographic media

A method for forming an image on a flexographic media includes providing a screened image; locating transition points from data regions to non-data regions in said screened image; determining a distance between pixels in adjacent data regions for each transition point; if the distance is greater than a predetermined distance, modify said screened image to remove a shoulder of pixels in contact with the transition point; and forming the modified screened image on the flexographic media.




i

Laser-assisted alignment of multi-station flexographic printing system

A multi-station flexographic printing system includes a plurality of flexographic printing stations. Each flexographic printing station includes a flexo master. Each flexo master comprises a Fresnel zone pattern in a unique position. A method of aligning a plurality of flexographic printing stations includes printing a Fresnel zone pattern on a substrate in a unique position for each flexographic printing station. Light is directed through the Fresnel zone patterns on the substrate. The light focused by the Fresnel zone patterns is captured with a sensor device.




i

Security device and its production method

A security device comprises two or more regions (1, 2). Each region (1, 2) contains a material or combination of materials wherein the two or more regions exhibit substantially the same visible appearance under first viewing conditions and different visible appearances under second viewing conditions, the second viewing conditions. The second viewing conditions comprise a combination of a) visible light and b) substantially any UV wavelength.




i

Printing system and printing method

A printing system includes a screen printing unit as a printing processor of a non-digital system and an ink jet printing device as a printing processor of a digital system. Holes as reference marks formed in a three-dimensional shape are provided on a placement table which is used commonly in the screen printing unit and the ink jet printing device. Positioning of printing positions is performed with reference to the same holes on both of the screen printing unit and the ink jet printing device.




i

Hot stamping printing device

A printing device 300 for printing elements in the form of sheets 10, includes a platen press 310 which hot stamps to affix to each sheet 10 with a colored or metallized film from at least one stamping strip 320. A transport device 340 introduces each sheet 10 one after the other into the platen press 310 by pulling the sheet 10 by its front edge. The printing device 300 further includes a device 360 able to partially restrain each sheet 10 by its rear portion during the phase of introducing the sheet 10 into the platen press 310.




i

Marking device for golf balls

A marking device for golf balls comprises a seat, an arch-shaped retainer, and a bottom plate. The seat defines a central recess and defines a bottom opening that communicates with the central recess. The seat is provided with an anti-slip pad within the central recess. Also, the seat is provided with upper positioning means and lower positioning means. The arch-shaped retainer is provided with retainer positioning means corresponding to the upper positioning means of the seat. The bottom plate is provided with plate positioning means corresponding to the lower positioning means of the seat. Therefore, the arch-shaped retainer and the bottom plate can be properly positioned on the seat. Furthermore, the arch-shaped retainer defines a central slit and the bottom plate defines a plurality of hollowed-out symbols. As such, the marking device can mark a line or symbol on a golf ball conveniently.




i

Method for changing edition on a rotary press

A method for successive printing of a first print job and a second print job on the same web using at least one printing group of the rotary press to print the first print job and the second print job is provided. The printing group includes at least a plate cylinder, a plate, a blanket cylinder and a blanket. Between the first print job and the second print job, a plate-changing stage occurs in which the blanket is held away from the web and the plates of the plate cylinder are changed. According to one aspect of the invention, between the first print job and the second print job, the web is kept traveling through the rotary press.




i

Laser-engraveable flexographic printing precursors and methods of imaging

A laser-engraveable flexographic printing precursor or patternable element comprises a laser-engraveable layer having two orthogonal dimensions. This laser-engraveable layer comprises one or more elastomeric resins and non-metallic fibers that are oriented in the laser-engraveable layer predominantly in one of its two orthogonal dimensions. The non-metallic fibers have an average length of at least 0.1 mm and an average diameter of at least 1 μm. The oriented non-metallic fibers reduce curl and shrinkage in the precursor and improve print quality and press life.




i

Wrinkle detection in continuous feed printers

A web printing system automatically detects the location of a wrinkle in a moving web. The web has a plurality of marked reference positions including an inboard position, a center position, and an outboard position. A plurality of contact image sensors detect the reference positions after the web passes through a spreader and an inboard distance and an outboard distance are respectively measured from the center position. If the inboard distance is less than a nominal inboard distance, the wrinkle is identified as inboard of the center position. If the outboard distance is less than a nominal outboard distance, the wrinkle is identified as outboard of the center position. The machine operator is notified of the fault condition and takes action to remedy the situation.




i

Screen printing device and an image recognizing method in the screen printing device

An imaging part in a screen printing device which images a board and a screen mask includes a single camera which is disposed with a posture of horizontally facing towards an incidence optical axis, a half mirror which makes an imaging light, which is incident through a lower imaging optical axis, to be incident on a camera, and a mirror which makes an imaging light, which is incident through an upper imaging optical axis, to pass through the half mirror and to be incident on the camera, and further has an upper illuminating part and a lower illuminating part which individually illuminate respective imaging objects. Imaging light is taken in the camera in a state that the upper illuminating part and the lower illuminating part are individually operated in a mask imaging step and a board imaging step, respectively.




i

Method and apparatus for orienting magnetic flakes

The invention relates to a method of aligning magnetic flakes, which includes: coating a substrate with a carrier having the flakes dispersed therein, moving the substrate in a magnetic field so as to align the flakes along force lines of the magnetic field in the absence of an effect from a solidifying means, and at least partially solidifying the carrier using a solidifying means while further moving the substrate in the magnetic field so as to secure the magnetic flakes in the carrier while the magnetic field maintains alignment of the magnetic flakes. An apparatus is provided, which has a belt for moving a substrate along a magnet assembly for aligning magnetic flakes. The apparatus also includes a solidifying means, such as a UV- or e-beam source, and a cover above a portion of the magnet assembly for protecting the flakes from the effect of the solidifying means.




i

Ink solutions for microcontact printing

An ink solution comprises (a) a solvent having (i) a boiling point between about 50° C. and about 100° C., (ii) a relative polarity of less than about 0.4, and (iii) a poly(dimethylsiloxane) swelling ratio of less than about 1.25; and (b) one or more dissolved organosulfur compounds, wherein each organosulfur compound has 10 or more carbon atoms. The one or more organosulfur compounds are present in a total concentration of at least about 3 mM, and the ink solution contains essentially no solid particles of the organosulfur compounds or solid particles derived from the organosulfur compounds.




i

Print substrate edge guide

In one example, a device for use in a printer includes a flexible piece and a holder configured to removably attach the piece to a platen that has a surface over which a print substrate is moved through the print zone for printing on the substrate. The piece and the holder are configured to place the piece in tension along the platen surface such that, when the piece is attached to the platen, the piece becomes sufficiently rigid to counter substrate edge curl.




i

Lithographic printing plate precursor

A positive-working lithographic printing plate precursor which comprises on a support having a hydrophilic surface or which is provided with a hydrophilic layer, a heat and/or light-sensitive coating comprising an infrared adsorbing agent and a binder including a monomeric unit including a salicylic acid group and a monomeric unit including a sulfonamide group.




i

Rotary system and method for printing containers

A system for digitally printing directly on a plurality of containers is provided. In an embodiment, the system includes a device configured to determine an initial position or orientation of an individual container; a plurality of print heads configured to print directly on said containers; and a plurality of container holders configured hold or retain an individual container, to rotate the individual container, and to maintain a rotational position of the individual container relative to at least one print head while printing occurs; and one or more curing devices. The system may be configured such that the plurality of container holders are configured to move along a linear or curved path, and the plurality of container holders may be configured to controllably rotate about a container axis.




i

Silk screen printing device with one main actuator

A device (1) for printing an impression by silk screen printing on at least one object (3), comprising of: a chassis (27); an object holder module (5) being movable relative to the chassis along a direction of pressing (Oz); a print head (7) including a screen holder module (29) and a squeegee holder module (31), the print head being movable relative to the chassis between an operating position close to the object holder module, and a maintenance position away from the object holder module, and an actuator (8) having a first part (125) and a second part (127) that is movable relative to the first part (125), the actuator (8) being adapted, in a first mode of operation, to be supported on the chassis by the first part and capable of moving the print head from the operating position to the maintenance position by a movement of the second part. The actuator is adapted, in a second mode of operation, to be supported on the chassis by the second part and is capable of moving the object holder module along the direction of pressing relative to the chassis by a movement of the first part.




i

Dampening fluid deposition by condensation in a digital lithographic system

A system and corresponding methods are disclosed for depositing of a layer of dampening fluid to a reimageable surface of an imaging member in a variable data lithography system by way of condensation. Dampening fluid in an airborne state is introduced proximate the reimageable surface in a condensation region. Conditions in the condensation region are such that the airborne dampening fluid preferentially condenses on the reimageable surface in a precisely controlled quantity, to thereby form a precisely controlled layer of dampening fluid of desired thickness over the reimageable surface. Among other advantages, improved print quality is obtained.




i

Apparatus for applying indicia on web substrates

A contact printing system is disclosed. A gravure cylinder having a plurality of discrete cells having an aspect ratio of at least about 25:1 disposed upon an outer surface thereof. A first portion of a first fluid and a second portion of a second fluid are disposed from a respective channel disposed internal to the gravure cylinder.




i

Lithographic printing plate precursor, lithographic printing plate platemaking method, and polymerizable monomer

There is provided a lithographic printing plate precursor that enables image recording using a laser and that provides an excellent scumming resistance and an excellent developability while maintaining a satisfactory printing durability. Also provided are a platemaking method, and a novel polymerizable monomer. A lithographic printing plate precursor has a support, and an image recording layer disposed thereon and containing a radical polymerization initiator and a polymerizable monomer that has a sulfonamide group and at least two ethylenically unsaturated groups; a lithographic printing plate platemaking method uses this lithographic printing plate precursor; and a polymerizable monomer has a sulfonamide group and at least two ethylenically unsaturated groups.




i

Method and an apparatus having a compressible collar for thermally treating a photosensitive precursor

The invention pertains to a method and apparatus for preparing a printing form from a precursor, particularly a method and apparatus for preparing the printing form by thermally treating a photosensitive precursor having a photopolymerizable layer. The method and apparatus includes heating the photosensitive precursor to a temperature sufficient to cause a portion of the layer to liquefy, contacting the precursor with a development medium to remove the liquefied material, and supporting a development medium with a core member adjacent an exterior surface of the photosensitive precursor, wherein a compressible collar of a closed-cell foam having a Poisson's ratio of less than 0.4 is disposed between the core member and the development medium.




i

Inductively heatable cylinder

A device for heating at least one tool that is disposed on the circumference of a rotating cylinder, for example on the circumference of an embossing cylinder. The embossing tool is produced from a magnetizable material and it is fixed to a carrier sleeve that is produced from a non-magnetizable material.




i

Embossing media

Apparatus for embossing media, the apparatus including cutter apparatus to cut a shape in a surface layer of a multi-layer substrate to form a die. The apparatus also includes an embosser to emboss the media using the die. The cutter apparatus is arranged to provide the die to the embosser.




i

Printer and method for transferring wiring patterns to objects

A printer according to the present invention includes a transfer roll and a plurality of the printing rolls. At least one printing roll of the plurality of the printing rolls transfers ink containing a conductive material to the transfer roll. Preferably, the at least one printing roll includes a printing roll configured to transfer ink containing a conductive material to the transfer roll and a printing roll configured to transfer ink containing a conductive material to the transfer roll.




i

Silicone rubber material for soft lithography

The present invention relates to a silicone rubber like material and a printing device including a stamp layer (100;201) comprising such a material. The material is suitable for use in soft lithography as it enables stable features having dimensions in the nanometer range to be obtained on a substrate, and also allows for the accommodation onto rough and non-flat substrate surfaces. The invention also relates to methods for manufacturing the silicone rubber like material and stamp layer (100;201) and use thereof in lithographic processes.




i

Method and system for applying customer-specific labels to unprinted side of printed products

Systems and methods for applying customer-specific labels to an unprinted or non-displayed side of printed products.




i

Printing plate and method for manufacturing same

The present invention relates to a cliché and a method for manufacturing the same, and the cliché according to the present invention comprises a cliché comprising: a groove pattern, wherein the groove pattern comprises a region composed of linear patterns which do not intersect with each other and the region composed of linear patterns is a square region comprising two or more lines of a linear pattern in the region and comprises a region in which the line width (W) and the depth (D) of the linear pattern and the ratio (R) of a region which does not comprise the linear pattern in the square region and the aperture line width (W0) of a mask pattern for forming a pattern, which corresponds to the linear pattern, satisfy specific relationship equation(s). The cliché according to the present invention may prevent the bottom touch phenomenon of ink transferred onto the cliché.




i

Image forming material, planographic printing plate precursor, and method for manufacturing a planographic printing plate

The invention provides an infrared-sensitive positive-working image forming material which provides excellent development latitude, image formability and image region strength, and in which decrease in development property is prevented even when a certain time has passed after pattern exposure until development treatment; an infrared-sensitive positive-working planographic printing plate precursor which is formed from the image forming material and has excellent image formability and image region printing durability; and a method for manufacturing a planographic printing plate using the planographic printing plate precursor. The image forming material includes; on a support, a lower layer containing a polymer having carboxylic acid groups at side chains thereof, at least a part of the carboxylic acid groups forming a salt structure with a monovalent basic compound, and an infrared absorbing agent; and an upper layer whose solubility to aqueous alkaline solution is increased by heat, in this order.




i

LOW POWER MODE WITH LEGACY COMPATIBILITY

During the development of Low Power Mode (LPM) (also known as L2 Mode) for DSL (Digital Subscriber Line) systems, it has become apparent that one of the most important issues is the impact on deployed legacy DSL systems. Legacy DSL systems are not capable of operating in the presence of large changes in crosstalk noise from neighbouring lines entering and exiting LPMs. For example, prior LPM methods at least do not assure that legacy lines will be protected to guarantee that no retrains will occur. These and other issues are addressed herein.




i

EQUALIZER CIRCUIT AND RECEIVING APPARATUS USING THE SAME

An equalizer circuit includes an phase-to-phase connectors including an phase-to-phase capacitor and four phase-to-phase switches, four output buffers, and control signal generation circuitry. One terminal of each phase-to-phase switches is connected to one of four connection paths on which four conversion signals being different in phase by 90° are input. The other one terminal of each phase-to-phase switches is connected to the phase-to-phase capacitor. Each output buffer is connected to one of the four connection paths and outputs an output signal. The control signal generation circuitry outputs control signals to control turning-on/off of the respective four phase-to-phase switches. A closing of the first, second, third, and fourth phase-to-phase switches are started from any one of phase-to-phase switches in one of a first ascending circulation and a first descending circulation based on the 4-phase control signals.




i

PHASE NOISE IMPROVEMENT TECHNIQUES FOR WIDEBAND FRACTIONAL-N SYNTHESIZERS

The disclosure provides a frequency synthesizer. It includes a PFD that generates an up signal and a down signal in response to a reference signal and a feedback signal. A charge pump generates a control voltage in response to the up signal and the down signal. A low pass filter generates a filtered voltage in response to the control voltage. An oscillator circuit generates an output signal in response to the filtered voltage. A feedback divider is coupled between the oscillator circuit and the PFD, and divides the output signal by a first integer divider to generate the feedback signal. A sigma delta modulator (SDM) generates a second integer divider in response to the feedback signal, the reference signal, the output signal and the first integer divider. A digital filter is coupled between the SDM and the feedback divider, and filters quantization noise associated with the SDM.




i

HALF-RATE CLOCK DATA RECOVERY CIRCUIT

A half-rate clock data recovery circuit includes: a voltage-controlled oscillator (VCO) for generating a data sampling clock and an edge sampling clock according to a control voltage; an adjusting circuit for dynamically controlling the VCO to adjust the phase difference between the data sampling clock and the edge sampling clock to be different from 90 degrees in multiple test periods; and a control circuit for instructing the adjusting circuit to respectively utilize different control value combinations to control the VCO in the multiple test periods, and for recording multiple recovered-signal quality indicators respectively corresponding to the multiple test periods. Afterwards, the control circuit instructs the adjusting circuit to utilize a control value combination corresponding to the best quality indicator among the multiple recovered-signal quality indicators to control the VCO.