WO2010026642A1 - 試験装置、送信装置、受信装置、試験方法、送信方法、および受信方法 - Google Patents
試験装置、送信装置、受信装置、試験方法、送信方法、および受信方法 Download PDFInfo
- Publication number
- WO2010026642A1 WO2010026642A1 PCT/JP2008/066005 JP2008066005W WO2010026642A1 WO 2010026642 A1 WO2010026642 A1 WO 2010026642A1 JP 2008066005 W JP2008066005 W JP 2008066005W WO 2010026642 A1 WO2010026642 A1 WO 2010026642A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- signal
- phase
- clock
- unit
- shift amount
- Prior art date
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/28—Testing of electronic circuits, e.g. by signal tracer
- G01R31/317—Testing of digital circuits
- G01R31/3181—Functional testing
- G01R31/319—Tester hardware, i.e. output processing circuits
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/28—Testing of electronic circuits, e.g. by signal tracer
- G01R31/317—Testing of digital circuits
- G01R31/3181—Functional testing
- G01R31/319—Tester hardware, i.e. output processing circuits
- G01R31/3193—Tester hardware, i.e. output processing circuits with comparison between actual response and known fault free response
- G01R31/31932—Comparators
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/28—Testing of electronic circuits, e.g. by signal tracer
- G01R31/317—Testing of digital circuits
- G01R31/31725—Timing aspects, e.g. clock distribution, skew, propagation delay
- G01R31/31726—Synchronization, e.g. of test, clock or strobe signals; Signals in different clock domains; Generation of Vernier signals; Comparison and adjustment of the signals
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K5/00—Manipulating of pulses not covered by one of the other main groups of this subclass
Definitions
- the present invention relates to a test apparatus, a transmission apparatus, a reception apparatus, a test method, a transmission method, and a reception method.
- Patent Document 1 discloses a test apparatus that tests a device under test that outputs a signal in which a clock is embedded.
- the test apparatus includes a PLL circuit that outputs a reproduction clock having a frequency that is a predetermined multiple of the frequency of a given reference clock and a phase delayed by a delay amount given from the phase of the given reference clock;
- a CDR circuit abbreviation for clock data recovery circuit
- a phase comparator that detects the phase difference between the clock embedded in the data signal and the recovered clock, and controls the amount of delay applied to the PLL circuit according to the phase difference;
- an output signal is acquired in accordance with the reproduction clock (see paragraphs 0017, 0023, and 0024).
- the phase comparator that compares the phase of the recovered clock and the data signal from the device generally outputs a state in which the recovered clock is either advanced or delayed with respect to the data signal from the device under test.
- a phase comparator When such a phase comparator outputs a burst signal that does not change for a long period of time, it may output either an advanced state or a delayed state for a long period of time.
- the phase of the recovered clock is unilaterally advanced or delayed, so that the recovered clock is out of the phase locked state with respect to the device under test.
- test clock cannot correctly capture the data signal because the reproduction clock is not locked to the data signal. For this reason, the test apparatus must wait until the reproduction clock is locked to the data signal, and the test time becomes long.
- an object of the present invention is to provide a test apparatus, a transmission apparatus, a reception apparatus, a test method, a transmission method, and a reception method that can solve the above problems.
- This object is achieved by a combination of features described in the independent claims.
- the dependent claims define further advantageous specific examples of the present invention.
- a test apparatus for testing a device under test, the phase of an internal clock generated in the test apparatus and a clock superimposed on a device signal output from the device under test
- a phase comparison unit that compares the phase shift amount of the internal clock with respect to the device signal based on a phase comparison result, and the internal clock with the phase shift amount adjusted with respect to the device signal.
- a test comprising: an acquisition unit that acquires the device signal; and a prohibition unit that prohibits a change in the phase shift amount based on the phase comparison result in at least a part of a period in which no clock is superimposed on the device signal.
- a test apparatus for testing a device under test, wherein the device under test is superimposed on an internal clock of the device under test and a reception signal input via an input terminal.
- a phase comparison unit that compares the phase with the clock, an adjustment unit that adjusts a phase shift amount of the internal clock with respect to the reception signal based on a phase comparison result, and a phase shift amount that is adjusted with respect to the reception signal
- An acquisition unit that acquires the received signal according to the internal clock, and the test apparatus supplies a test signal for testing the device under test to the input terminal of the device under test.
- Prohibition of the change of the phase shift amount based on the phase comparison result in at least a part of a period when the clock is not superimposed on the signal supply unit and the test signal.
- a signal test device comprising a prohibition unit supplied to the device under test, the, and to provide a test method related to the test apparatus.
- the phase comparison unit that compares the phase of the reference clock and the clock superimposed on the received signal from the outside, and the reference clock for the received signal based on the result of the phase comparison
- An adjustment unit that adjusts a phase shift amount; an acquisition unit that acquires the reception signal according to the reference clock whose phase shift amount is adjusted with respect to the reception signal; and a period in which no clock is superimposed on the reception signal
- a reception device including a prohibition unit that prohibits a change in the phase shift amount based on the phase comparison result, and a reception method related to the reception device.
- a transmitting device for transmitting a signal to a receiving device, wherein the receiving device is superimposed on a received signal input via a reference clock and an input terminal of the receiving device.
- a phase comparison unit that compares the phase with the received clock, an adjustment unit that adjusts a phase shift amount of the reference clock with respect to the received signal based on a phase comparison result, and a phase shift amount that is adjusted with respect to the received signal.
- An acquisition unit that acquires the reception signal according to the reference clock, and the transmission device supplies a transmission signal to be transmitted to the reception device to the input terminal of the reception device.
- a prohibiting unit that prohibits a change in the amount of phase shift based on the phase comparison result in at least a part of a period in which a clock is not superimposed on the transmission signal.
- FIG. 1 shows a configuration of a test apparatus 10 according to an embodiment of the present invention.
- 2 shows a configuration of a shift clock generation unit 150 according to an embodiment of the present invention.
- the structure of the phase adjustment control part 260 which concerns on embodiment of this invention is shown.
- An example of the operation timing of the test apparatus 10 according to the embodiment of the present invention is shown.
- the structure of the principal part of the determination part 124 which concerns on the 1st modification of embodiment of this invention is shown.
- the structure of the test apparatus 10 which concerns on the 2nd modification of embodiment of this invention is shown.
- the structure of the apparatus 700 which concerns on the 3rd modification of embodiment of this invention is shown.
- the structure of the determination part 124 which concerns on the 4th modification of embodiment of this invention is shown.
- movement of the phase comparison part 810 which concerns on the 4th modification of embodiment of this invention is shown typically.
- FIG. 1 shows a configuration of a test apparatus 10 according to the present embodiment together with a DUT 100 (device under test or Device Under Test).
- the test apparatus 10 causes the internal clock generated in the test apparatus 10 to be phase-locked with the clock extracted from the device signal.
- the test apparatus 10 prohibits the change of the phase of the internal clock during a period in which the clock is not superimposed on the device signal.
- the test apparatus 10 can maintain the phase of the internal clock in the previous lock state while receiving the burst signal as the device signal. Therefore, when the data signal is output again from the DUT 100, the test apparatus 10 can receive the data signal using the phase of the internal clock in the immediately previous lock state.
- the test apparatus 10 includes a test apparatus main body 105 that tests the DUT 100 and a control apparatus 110 that controls the test of the DUT 100 performed by the test apparatus main body 105.
- the test apparatus main body 105 executes a test sequence for testing the DUT 100, supplies a test signal generated according to the test sequence to the DUT 100, and device signals output from the DUT 100 according to the test signal.
- a determination unit 124 that receives and inspects and determines whether the DUT 100 is good or bad.
- the test unit 122 includes a frequency multiplication unit 145, a timing generation unit 125, a pattern generation unit 130, and a waveform shaping unit 135.
- the frequency multiplier 145 multiplies the reference clock REFCLK of the test apparatus 10 and outputs a multiplied clock REFCLKM.
- the frequency multiplier 145 may output a multiplied clock REFCLKM converted to the same frequency as the device signal output from the DUT 100.
- the frequency multiplier 145 outputs a multiplied clock REFCLKM having a frequency different from that of the device signal.
- 125 may be converted to the same frequency as the device signal.
- the reference clock REFCLK may be a system clock for operating the entire test apparatus main body 105, or may be a reference clock used for exchanging signals with the DUT 100. Further, depending on the frequency relationship between the reference clock REFCLK and the clock superimposed on the device signal, a configuration without the frequency multiplier 145 or a configuration using a frequency divider instead of the frequency multiplier 145 may be employed.
- the timing generator 125 receives the reference clock REFCLK and the multiplied clock REFCLKM multiplied by the frequency multiplier 145, receives a periodic signal (also referred to as a RATE signal) indicating a test period for testing the DUT 100, and a test signal supplied to the DUT 100. A timing signal that defines the change timing is generated.
- the timing generation unit 125 is a device that changes the frequency and / or phase of the reference clock REFCLK and / or the multiplied clock REFCLKM, and is a clock that is a source of the shift clock SFTCLK used by the determination unit 124 to acquire a device signal.
- a strobe signal STRB adjusted to substantially the same frequency as the signal is generated.
- the strobe signal STRB is an example of an internal clock generated in the test apparatus 10.
- the timing generation unit 125 thins out the clock pulses of the multiplied clock REFCLKM so that the frequency of the generated strobe signal STRB is the same as the frequency of the device signal, and adjusts the interval of the clock pulses to be equal.
- the signal STRB may be generated.
- the timing generator 125 divides at least one of the reference clock REFCLK or the multiplied clock REFCLKM and the strobe signal STRB oscillated by a VCO (voltage controlled oscillator) or the like to obtain the same frequency, and then divides the reference clock REFCLK.
- the phase adjustment may be performed by controlling the oscillation frequency of the VCO so that the clock based on the strobe signal STRB is phase-locked with the clock based on the multiplied clock REFCLKM.
- the pattern generator 130 executes a test command in a test sequence based on a test program supplied from the control device 110 for each test cycle corresponding to the periodic signal received from the timing generator 125, and associates the test command with each test command.
- the obtained test pattern is output to the waveform shaping unit 135.
- the pattern generation unit 130 outputs an expected value pattern associated with each test instruction to the expected value comparison unit 170.
- the waveform shaping unit 135 shapes the test pattern received from the pattern generation unit 130 so as to change at a timing corresponding to the timing signal received from the timing generation unit 125 to generate a test signal. Then, the waveform shaping unit 135 supplies the generated test signal to the DUT 100.
- the test unit 122 may supply a test signal similar to the actual operation to the DUT 100. Instead, a test scan path or the like may be provided. It may be used to set the DUT 100 to output a device signal to be tested. Further, the test unit 122 may supply a digital or analog test signal according to the type of the DUT 100.
- the determination unit 124 includes a comparator 140, a shift clock generation unit 150, an acquisition unit 155, a frequency division unit 160, a DEMUX 165, and an expected value comparison unit 170.
- the comparator 140 receives the device signal output from the DUT 100 and converts it into a signal waveform used inside the determination unit 124. In the present embodiment, the comparator 140 compares the device signal with a threshold voltage corresponding to the logical value, and outputs a logical value corresponding to the comparison result.
- the shift clock generation unit 150 adjusts the phase of the strobe signal STRB generated by the control device 110 according to the device signal received via the comparator 140, and adjusts the amount of phase shift with respect to the device signal.
- a shift clock SFTCLK is generated.
- Shift clock generation unit 150 outputs generated shift clock SFTCLK to acquisition unit 155 and frequency division unit 160. Further, the shift clock generation unit 150 determines whether to permit or prohibit the phase adjustment according to an instruction from the control device 110 and the pattern generation unit 130 or an observation result of the device signal received from the DEMUX 165.
- the acquisition unit 155 is, for example, an FF (short for a flip-flop), and acquires a device signal according to the shift clock SFTCLK.
- the frequency divider 160 divides the shift clock SFTCLK and supplies the frequency-shifted clock SFTCLKD to the shift clock generator 150 and the DEMUX 165.
- the DEMUX 165 (abbreviation for demultiplexer) demultiplexes the device signal acquired by the acquisition unit 155 according to the divided shift clock SFTCLKD, and compares the demultiplexed device signal with the shift clock generation unit 150 and the expected value comparison.
- the frequency divider 160 may divide the shift clock SFTCLK and output a frequency-divided shift clock SFTCLKD having the same frequency as the periodic signal RATE or the reference clock REFCLK.
- the DEMUX 165 parallelizes the device signals that the acquisition unit 155 sequentially captures in synchronization with the shift clock SFTCLK, and converts the device signals into multi-bit device signals that are synchronized with the divided shift clock SFTCLKD. For example, when the frequency division ratio is 1: 8, the DEMUX 165 allocates continuous 8-bit device signals sequentially acquired by the acquisition unit 155 to each bit of 8-bit data, and the frequency is 1/8. Convert data into device signals.
- the expected value comparison unit 170 receives the demultiplexed device signal from the DEMUX 165 and compares it with the corresponding expected value in the expected value pattern supplied from the pattern generation unit 130. Accordingly, the expected value comparison unit 170 can compare the value of the device signal from the DUT 100 acquired by the acquisition unit 155 with the expected value.
- the expected value comparison unit 170 may store the comparison result between the value of the device signal and the expected value in a storage device such as a fail memory or a register.
- the control device 110 can detect whether or not a failure has occurred by accessing the storage device during or after the test and notify the user of the test device 10. Further, the test apparatus 10 may change the test sequence to be executed depending on whether or not a failure has occurred.
- the control device 110 controls each part of the test apparatus main body 105.
- the control device 110 includes a frequency multiplication unit 145, a timing generation unit 125, a pattern generation unit 130, a waveform shaping unit 135, a comparator 140, a shift clock generation unit 150, a DEMUX 165, an expected value comparison unit 170, and the like in the test apparatus main body 105.
- a register or memory provided in each unit is accessed to set the function and operation of each unit.
- the control device 110 may set the frequency multiplication unit 145 to multiply the multiplied clock REFCLKM with respect to the reference clock REFCLK, and set the frequency ratio between the multiplied clock REFCLKM and the strobe signal STRB in the timing generation unit 125.
- the shift clock generation unit 150 may set whether to prohibit the phase adjustment. Further, the control device 110 may set the frequency division ratio of the frequency-divided shift clock SFTCLKD with respect to the shift clock SFTCLK in the frequency division unit 160, and how many bits the device signal received from the acquisition unit 155 is demultiplexed. You may set to DEMUX165.
- FIG. 2 shows a configuration of the shift clock generation unit 150 according to the present embodiment.
- the shift clock generation unit 150 includes a clock recovery unit 200, a phase comparison unit 210, a digital filter 220, a register 225, a jitter application unit 230, an adder 240, a phase shift unit 250, and a phase adjustment control unit 260.
- a clock recovery unit 200 includes a clock recovery unit 200, a phase comparison unit 210, a digital filter 220, a register 225, a jitter application unit 230, an adder 240, a phase shift unit 250, and a phase adjustment control unit 260.
- the clock recovery unit 200 recovers the clock of the device signal from the device signal output from the DUT 100. Specifically, the clock recovery unit 200 outputs a recovered clock RCLK having an edge corresponding to the edge timing at which the logical value of the device signal changes. As an example, the clock recovery unit 200 has the same edge as the device signal by taking the exclusive OR (or the negative exclusive OR) of the device signal and the delayed device signal obtained by delaying the device signal for a predetermined time, A reproduction clock RCLK having a pulse width of a predetermined time may be generated.
- the phase comparison unit 210 compares the phase of the strobe signal STRB and the recovered clock RCLK obtained by extracting the clock superimposed on the device signal. Then, the phase comparison unit 210 is a delayed signal L (Late signal) indicating that the edge of the strobe signal STRB is delayed with respect to the edge of the recovered clock RCLK from which the clock superimposed on the device signal is extracted, or advanced. A lead signal E (Early signal) indicating that the signal is present is output as a phase comparison result.
- the phase comparison unit 210 may be a phase frequency comparator (PFD: Phase Frequency Detector) or a phase comparator (PD: Phase Detector).
- the advance signal E and the delay signal L may be a pulse width modulation digital signal having a pulse width corresponding to the advance or delay, or a 1-bit signal having a logical value corresponding to the advance or delay. Also good.
- the digital filter 220, the register 225, the jitter applying unit 230, the adder 240, and the phase shift unit 250 are adjustment units that adjust the phase shift amount of the strobe signal STRB with respect to the device signal based on the phase comparison result by the phase comparison unit 210. Function as.
- the digital filter 220 supplies the phase shift unit 250 with a phase control signal for controlling the phase shift unit 250 according to the advance signal E and the delay signal L that are sequentially input, thereby reducing the phase shift amount of the phase shift unit 250. Control. More specifically, the digital filter 220 increases the phase shift amount when the advance signal E is received as the phase comparison result on condition that the phase adjustment control unit 260 does not prohibit the change of the phase shift amount. When the delay signal L is received as a phase comparison result, the phase shift amount is decreased. In addition, the digital filter 220 does not change the phase shift amount of the adjustment unit on condition that the phase adjustment control unit 260 prohibits the change of the phase shift amount.
- the digital filter 220 may integrate the advance signal E and the delay signal L and output the integrated value as a phase control signal.
- the digital filter 220 may include a counter that counts up in a cycle in which the advance signal E is received and counts down in a cycle in which the delay signal L is received when the change of the phase shift amount is not prohibited.
- the digital filter 220 may output a phase control signal based on the count value, that is, for example, a predetermined number of bits from the higher order of the count value as the phase control signal.
- the digital filter 220 may be an infinite impulse response filter (IIR filter) or a finite impulse response filter (FIR filter).
- the register 225 is a save destination for saving the phase shift amount of the strobe signal STRB specified by the digital filter 220.
- the register 225 receives and stores the count value of the counter in the digital filter 220 from the digital filter 220 in response to an instruction from the phase adjustment control unit 260 to the digital filter 220.
- the digital filter 220 can restore the saved phase shift amount by restoring the count value saved in the register 225 to the counter in the digital filter 220.
- the jitter applying unit 230 generates a jitter signal to be superimposed on the shift clock SFTCLK when performing a jitter tolerance test on the device signal output from the DUT 100, and outputs the jitter signal to the phase control signal output from the digital filter 220 via the adder 240. to add. Thereby, the jitter applying unit 230 and the adder 240 change the value of the phase control signal output from the digital filter 220 according to the value of the jitter signal to be superimposed, and supply the value to the phase shift unit 250.
- the phase shift unit 250 is, for example, a variable delay circuit, receives a phase control signal to which jitter is added as necessary from the adder 240, and delays the strobe signal STRB by a delay amount corresponding to the phase control signal.
- the phase shift unit 250 shifts the strobe signal STRB by the phase shift amount specified by the phase control signal with respect to the device signal, and outputs the result as the shift clock SFTCLK.
- the digital filter 220 increases the phase shift amount, so that the phase shift unit 250 further delays the phase of the shift clock SFTCLK and shifts the phase. Match.
- the digital filter 220 decreases the phase shift amount, so the phase shift unit 250 further advances the phase of the shift clock SFTCLK to match the phase.
- the phase adjustment control unit 260 controls whether the change of the phase shift amount of the digital filter 220 is permitted or prohibited.
- the phase adjustment control unit 260 functions as a prohibition unit that prohibits the change of the phase shift amount based on the phase comparison result during at least a part of the period in which the clock is not superimposed on the device signal.
- FIG. 3 shows a configuration of the phase adjustment control unit 260 according to the present embodiment.
- the phase adjustment control unit 260 includes a detection unit 300, an OR circuit 310, an FF 320, a buffer 325, an FF 330, and a logic circuit 340.
- the phase adjustment control unit 260 performs control from the control device 110, control from the pattern generation unit 130, or Whether or not to allow the phase shift unit 250 to change the phase shift amount is controlled based on the expected value or the measurement result of the change in the device signal by the detection unit 300.
- the detection unit 300 receives the device signal acquired by the acquisition unit 155 via the DEMUX 165, detects that the value of the device signal does not change for a predetermined period, and detects the phase shift amount of the digital filter 220.
- a prohibition signal A (in this figure, a signal having a logical value H) for prohibiting the change is output to the logical sum circuit 310. Accordingly, the detection unit 300 prohibits the digital filter 220 from changing the phase shift amount based on the phase comparison result.
- the detection unit 300 is measured by a run-length measurement circuit that measures the number of cycles (or the number of bits) in which the value of the device signal is unchanged or the device signal does not have a clock edge, and is measured by the run-length measurement circuit.
- a determination circuit that outputs a detection signal to the OR circuit 310 when the invariant cycle number (or invariant bit number) becomes larger than a predetermined value may be included.
- the detection unit 300 detects the prohibition signal when the value of the device signal changes during a predetermined period or when the number of cycles in which the device signal has a clock edge is equal to or less than a predetermined threshold.
- A may be output to the OR circuit 310.
- the detection unit 300 can prohibit the change of the phase shift amount in response to the frequency of the clock pulse included in the device signal being reduced to such an extent that the phase locked state cannot be maintained.
- the detection unit 300 adjusts the phase until the detection that the value of the device signal does not change in response to the detection that the value of the device signal acquired by the acquisition unit 155 does not change.
- a save signal instructing to save the shift amount in the register 225 is output to the digital filter 220.
- the detection unit 300 detects a change from a cycle in which the device signal has changed and a clock edge to a cycle in which the device signal does not change and does not have a clock edge, and instructs the digital filter 220 to save the phase shift amount. You can do it. Instead, the detection unit 300 instructs the digital filter 220 to save the phase shift amount when it detects that the value of the device signal does not change for a period shorter than the period for which the prohibition signal A is output. You can do it.
- the detection unit 300 uses the phase shift amount saved in the register 225 as the phase shift amount of the reference clock with respect to the device signal.
- a recovery signal instructing the digital filter 220 to be reset is output to the digital filter 220.
- the control device 110 uses the period used for outputting the prohibition signal A, the threshold value for the invariant cycle number or the threshold value for the change cycle number, and / or the period used for outputting the save signal before or during the test execution.
- at least one of the various parameters may be set based on the user's designation.
- the pattern generation unit 130 may set at least one of the various parameters described above based on the designation of a test command or a test pattern during the execution of the test sequence.
- the logical sum circuit 310 calculates the logical sum of the prohibition signal A from the detection unit 300, the prohibition signal B received from the control device 110, and the prohibition signal C received from the pattern generation unit 130, and outputs the prohibition signal D. .
- the control device 110 prohibits the change of the phase shift amount in the digital filter 220 during the period between the tests or according to the user's designation. Is output.
- the pattern generation unit 130 outputs a prohibition signal C (a signal having a logical value H) in order to prohibit the change of the phase shift amount by the digital filter 220 during the period in which the change of the phase shift amount is prohibited in the test sequence.
- the user can prohibit the change of the phase shift amount during a period in which a device signal in which no clock is superimposed is output from the DUT 100 during the test, for example, by explicitly specifying the test command or test pattern. it can.
- the logical sum circuit 310 outputs a prohibition signal D obtained by logically summing the prohibition signal A, the prohibition signal B, and the prohibition signal C, so that any one of the detection unit 300, the control device 110, and the pattern generation unit 130 is output.
- the digital filter 220 is prohibited from changing the phase shift amount based on the phase comparison result.
- the phase adjustment control unit 260 may determine whether to prohibit the change of the phase shift amount by the digital filter 220 based on the expected value generated by the pattern generation unit 130. . More specifically, the phase adjustment control unit 260 detects when the expected value does not change for a predetermined period or more, or when the expected value permits a don't care for a predetermined period or more, that is, when an arbitrary value is permitted as a device signal. This may be detected in the same manner as the unit 300, and a prohibition signal may be output to the OR circuit 310.
- the FF 320, the buffer 325, the FF 330, and the logic circuit 340 are provided to supply the prohibition signal D to the digital filter 220 in synchronization with the divided shift clock SFTCLKD.
- the FF 320 acquires the prohibition signal D at the timing of the divided shift clock SFTCLKD.
- the buffer 325 delays the divided shift clock SFTCLKD for a time sufficiently smaller than one cycle.
- the FF 330 acquires the prohibition signal D acquired by the FF 320 at the timing of the divided shift clock SFTCLKD delayed by the buffer 325.
- the FF 320 and the FF 330 can prevent malfunction due to glitches when the prohibition signal D that changes in synchronization with the reference clock REFCLK or the strobe signal STRB in the test apparatus is synchronized with the divided shift clock SFTCLKD.
- the logic circuit 340 obtains the logical product of the negation of the prohibition signal D and the divided shift clock SFTCLKD and supplies it to the digital filter 220. As a result, the logic circuit 340 passes the divided shift clock SFTCLKD when allowing the change of the phase shift amount, and masks the divided shift clock SFTCLKD so as not to pass when changing the phase shift amount is prohibited. To do. As a result, the phase adjustment control unit 260 can prohibit the change of the phase shift amount by stopping the clock operation of the digital filter 220.
- the digital filter 220 is connected to the phase shift unit 250 based on the phase comparison result of the phase comparison unit 210 in at least a part of the period when the clock is not superimposed on the device output signal output from the DUT 100. It is prohibited to change the amount of phase shift caused by. As a result, the test apparatus 10 can prevent the phase shift amount from deviating from the phase locked state during the period when the clock is not superimposed.
- FIG. 4 shows an example of the operation timing of the test apparatus 10 according to the present embodiment.
- the DUT 100 outputs a data signal 400 with a clock superimposed thereon as a device signal, and then outputs a burst signal 410 in which the value does not change for a certain period and the clock is not superimposed. Then, the DUT 100 outputs a data signal 420 in which a clock is superimposed again after the burst signal 410.
- the phase comparison unit 210 compares the phases of the recovered clock RCLK extracted from the data signal 400 and the strobe signal STRB, and adjusts the phase of the shift clock SFTCLK based on the phase comparison result. Thereby, the phase of the shift clock SFTCLK is locked with respect to the device signal. This state is indicated by hatching in the CDR lock state 430 in the drawing.
- the digital filter 220 is in an operation state shown as a CDR lock state 430, a CDR lock release state 440, and a CDR lock state 450 in the drawing.
- the clock recovery unit 200 cannot extract the clock from the device signal, and the phase comparison unit 210 cannot compare the phase of the recovery clock RCLK and the strobe signal STRB. . In this case, depending on the type of the phase comparison unit 210, either the advance signal or the delay signal continues to be output.
- phase comparison unit 210 an FF that takes in logic H at the edge of the recovered clock and outputs it as a delay signal, an FF that outputs as an advance signal that takes in logic H at the edge of the strobe signal STRB, and these two A phase frequency comparator having a circuit that resets two FFs to logic L when both outputs of the FFs become logic H can be cited.
- the phase comparison unit 210 continues to output one of the advance signal and the delay signal, the digital filter 220, when the change of the phase shift amount is not prohibited, as shown in the CDR lock state 430 in the figure, the phase comparison result In response to this, the phase shift amount is shifted in one direction, and the state is gradually shifted to the CDR lock release state 440 in which the phase lock is released. Thereafter, when the data signal 420 is output from the DUT 100, the phase comparison unit 210 can again perform the phase comparison between the recovered clock RCLK and the strobe signal STRB. As a result, the digital filter 220 gradually shifts the operation state from the CDR unlocked state 440 in which the phase lock is released to the CDR locked state 430 in which the phase lock is released.
- the phase adjustment control unit 260 does not prohibit the change of the phase shift amount, the phase shift amount changes in one direction while the DUT 100 outputs the burst signal 410, and the DUT 100 again receives the data. For a while after the output of the signal 420, the phase lock is released. Therefore, the test cannot be performed for a while after the DUT 100 starts outputting the data signal, and the test time becomes long.
- the pattern generator 130 sets the digital filter 220 to the CDR operation mode 460 by setting the inhibition signal C to logic L while the DUT 100 outputs the data signal 400. Accordingly, the pattern generation unit 130 allows the digital filter 220 to maintain the phase locked state by changing the phase shift amount following the device signal, and sets the CDR locked state 475.
- the pattern generating unit 130 sets the inhibition signal C to logic H.
- the digital filter 220 transitions from the CDR operation mode 460 to the CDR stop mode 465 and enters a CDR function stop state 480 that maintains the phase shift amount as it was immediately before the prohibition signal C was received.
- the pattern generation unit 130 sets the prohibition signal C to logic L again, sets the digital filter 220 to the CDR lock state 485, and permits the change of the maintained phase shift amount. .
- the digital filter 220 can hold the phase shift amount in the immediately previous phase lock state during the period in which phase alignment is not possible. Therefore, if a large phase shift does not occur between the clocks of the test apparatus 10 and the DUT 100 during the period in which the DUT 100 outputs the burst signal 410, the test apparatus 10 may start the output of the data signal 420 or after the output starts. After a relatively short time, the phase lock state can be restored.
- the example in which the prohibition signal C is switched at almost the same timing as when the device signal is switched from the data signal to the burst signal is shown.
- some time is required until the change of the phase shift amount is prohibited after the device signal is switched from the data signal to the burst signal.
- the detection unit 300 detects that the value of the device signal acquired by the acquisition unit 155 does not change for a predetermined period or longer, the detection unit 300 sets the prohibition signal A to logic H.
- the burst signal 410 starts to be output after the data signal 400 as the device signal, the phase shift amount is changed at least for a specified period.
- the digital filter 220 may cancel the change in the phase shift amount during the period specified in advance. That is, for example, when the device signal is switched from the data signal 400 to the burst signal 410, the digital filter 220 receives the save signal from the detection unit 300 and saves the phase shift amount in the digital filter 220 to the register 225. The digital filter 220 receives the recovery signal from the detection unit 300 when the value of the device signal acquired by the acquisition unit 155 does not change for a predetermined period or longer, and uses the phase shift amount saved in the register 225 as the device signal. The phase shift amount of the reference clock with respect to is reset.
- the digital filter 220 applies the length of this period to the phase comparison unit 210 that continues to decrease the phase shift amount during this period.
- the phase comparison unit 210 that increases the phase shift amount by the number of cycles corresponding to the period and continues to increase the phase shift amount during this period, the phase shift amount is decreased by the number of cycles corresponding to the length of this period. Also good. Since the increase / decrease amount of the phase shift amount is determined by the length of the designated period, the digital filter 220 may store the increase / decrease amount as a constant in advance. Thereby, the digital filter 220 can cancel the change in the phase shift amount during this period.
- FIG. 5 shows a configuration of a main part of the determination unit 124 according to the first modification of the present embodiment.
- the determination unit 124 according to the present modification adjusts the phase of the shift clock according to the clock superimposed on the device signal by a method different from that shown in FIGS.
- members having the same reference numerals as those in FIGS. 1 to 4 have the same functions and configurations as those in FIGS.
- the determination unit 124 includes a comparator 140, a PLL unit 500 (abbreviation of Phase Locked Loop), a variable delay circuit 540, a CDR circuit 550, a phase adjustment control unit 260, and an acquisition unit 155. .
- the PLL unit 500 outputs a shift clock SFTCLK that is synchronized with the strobe signal STRB and has a phase difference corresponding to the delay amount input from the CDR circuit 550 with respect to the strobe signal STRB.
- the PLL unit 500 includes a phase comparison unit 505, an adder 510, an LPF 515 (abbreviation for low-pass filter), a VCO 520 (abbreviation for voltage-controlled oscillator), a frequency divider 525, and a frequency divider 530.
- the phase comparison unit 505 detects the phase difference between the clock obtained by dividing the shift clock SFTCLK output from the frequency divider 530 to the frequency of the strobe signal STRB and the strobe signal STRB, and indicates a phase difference signal indicating the phase difference. Is output.
- the adder 510 adds the delay amount received from the CDR circuit 550 to the phase difference signal from the phase comparison unit 505.
- the LPF 515 limits or attenuates a high frequency component of a predetermined frequency or higher in the phase difference signal to which the delay amount from the CDR circuit 550 is added, and passes a low frequency component lower than the predetermined frequency.
- the VCO 520 oscillates at a frequency corresponding to the voltage of the phase difference signal passed by the LPF 515 and outputs an oscillation clock.
- the frequency divider 525 divides the oscillation clock into, for example, 1 / N1 to divide the frequency to a frequency according to the clock superimposed on the device signal, and obtains the acquisition unit 155, the frequency divider 530, and the variable delay circuit. 540.
- the frequency divider 530 divides the shift clock SFTCLK to 1 / N2, for example, to divide the frequency of the strobe signal STRB.
- the variable delay circuit 540 delays the shift clock SFTCLK by a time corresponding to about a half cycle of the device signal.
- the CDR circuit 550 supplies a delay amount supplied to the adder 510 in the PLL unit 500 so as to reduce the phase difference between the shift clock SFTCLK delayed by the variable delay circuit 540 and the clock superimposed on the device signal. Control. Thereby, the CDR circuit 550 adjusts the phase of the shift clock SFTCLK supplied to the acquisition unit 155 so as to be approximately in the middle of the clock change points superimposed on the device signal.
- the CDR circuit 550 includes a phase comparison unit 210, a digital filter 220, a register 225, an offset delay amount storage unit 570, an adder 575, and a DA conversion unit 580.
- the offset delay amount storage unit 570 stores an offset delay amount set by the control device 110 or the like. The user of the test apparatus 10 can change the phase of the shift clock SFTCLK with respect to the device signal according to the test contents by designating the offset delay amount.
- the adder 575 adds the phase shift amount output from the digital filter 220 and the offset delay amount from the offset delay amount storage unit 570, and calculates a delay amount to delay the shift clock SFTCLK with respect to the strobe signal STRB.
- the DA conversion unit 580 converts the digital delay amount output from the adder 575 into an analog delay amount and supplies the analog delay amount to the adder 510 in the PLL unit 500.
- the device signal can be acquired using the shift clock SFTCLK that is synchronized with the strobe signal STRB and has a predetermined phase difference with respect to the strobe signal STRB. Further, the phase adjustment control unit 260 can prohibit the change of the phase shift amount by the digital filter 220 during at least a part of the period when the clock is not superimposed on the device signal.
- FIG. 6 shows the configuration of the test apparatus 10 according to the second modification of the present embodiment together with the DUT 100.
- members having the same reference numerals as those in FIGS. 1 to 5 have the same functions and configurations as those in FIGS.
- the DUT 100 has a function of receiving a signal on which a clock is superimposed via an input terminal.
- the test apparatus 10 prohibits the phase adjustment in the DUT 100 during at least a part of the period in which the clock is not superimposed on the test signal supplied to the input terminal of the DUT 100, thereby setting the phase lock state between the test apparatus 10 and the DUT 100. maintain.
- the DUT 100 includes an internal circuit 602, an output IF circuit 622 (abbreviation of output interface circuit), a phase adjustment control unit 660, and an input IF circuit 624 (abbreviation of input interface circuit).
- the internal circuit 602 is a circuit designed according to the purpose of use of the DUT 100, and operates according to the externally received signal received via the input IF circuit 624 and the internal state of the internal circuit 602, and is necessary. In response, a transmission signal is transmitted to the outside via the output IF circuit 622 or the like.
- the output IF circuit 622 is controlled by the internal circuit 602 and functions as a transmission device.
- the output IF circuit 622 receives the reference clock REFCLK and the transmission data SDATA inside the DUT 100 and transmits them as a transmission signal to the outside.
- the output IF circuit 622 serializes the transmission data SDATA and transmits a transmission signal on which a reference clock REFCLK or a multiplied clock REFCLKM obtained by multiplying the reference clock REFCLK is superimposed.
- the phase adjustment control unit 660 operates based on the reference clock REFCLK in the DUT 100.
- the phase adjustment control unit 660 is a phase adjustment control unit 260 provided in the determination unit 124 of the test apparatus main body 105 in at least a part of a period in which the multiplied clock REFCLKM is not superimposed on the transmission signal transmitted by the output IF circuit 622.
- a prohibition signal for instructing prohibition of the change of the phase shift amount based on the phase comparison result of the phase comparison unit 210 is transmitted.
- the phase adjustment control unit 660 includes the detection unit 300 and the OR circuit 310 illustrated in FIG. 3, and sends a prohibition signal to the determination unit 124 in the test apparatus main body 105 in the same manner as the phase adjustment control unit 260 illustrated in FIG. 3. Send to.
- the phase adjustment control unit 660 may transmit a prohibition signal received from the internal circuit 602 to the determination unit 124 in the test apparatus main body 105 when the data signal is not transmitted.
- the phase adjustment control unit 660 may transmit the prohibition signal to the determination unit 124 in the test apparatus main body 105 when the value of the transmission data SDATA or the transmission signal does not change for a predetermined period or longer.
- the input IF circuit 624 is controlled by the internal circuit 602 and functions as a receiving device.
- the input IF circuit 624 receives the reference clock REFCLK inside the DUT 100 from the internal circuit 602, receives a reception signal input from the outside via the input terminal, and supplies the reception data RDATA to the internal circuit 602.
- Input IF circuit 624 includes a comparator 140, a frequency multiplier 145, a shift clock generator 150, an acquisition unit 155, a frequency divider 160, and a DEMUX 165. Since the functions and operations of these members are the same as those of the members having the same reference numerals in FIGS. 1 to 4, the description thereof will be omitted except for the differences.
- the shift clock generation unit 150 in the input IF circuit 624 is abbreviated as in FIG. 2 except for the main difference that the reference clock REFCLK in the DUT 100 is multiplied by the frequency multiplication unit 145 to be used as an internal clock for obtaining the received signal.
- the same configuration is taken.
- the clock recovery unit 200 in the shift clock generation unit 150 recovers a clock superimposed on a reception signal input from the outside via an input terminal.
- the phase comparison unit 210 in the shift clock generation unit 150 compares the phase of the multiplied clock REFCLKM obtained by multiplying the reference clock REFCLK of the DUT 100 with the recovered clock obtained by extracting the clock superimposed on the received signal.
- the digital filter 220, the register 225, the jitter applying unit 230, and the phase shift unit 250 in the shift clock generation unit 150 adjust the phase shift amount of the multiplied clock REFCLKM with respect to the received signal based on the phase comparison result.
- the input IF circuit 624 since the input IF circuit 624 only needs to satisfy the function as a receiving device, the input IF circuit 624 generates the shift clock SFTCLK using the strobe signal STRB generated by the timing generation unit 125 like the determination unit 124 shown in FIG. It does not have to be.
- the shift clock generation unit 150 may not include the jitter application unit 230 and the adder 240. Further, the DUT 100 incorporates clock conversion circuit parts such as the FF 320, the buffer 325, the FF 330, and the logic circuit 340 in the phase adjustment control unit 260 shown in FIG.
- the prohibition signal D may be input from outside the DUT 100. Instead, the shift clock generation unit 150 in the input IF circuit 624 further includes the detection unit 300 and the OR circuit 310 in the phase adjustment control unit 260 shown in FIG. 3, and a clock is superimposed on the received signal. The change of the phase shift amount based on the phase comparison result may be prohibited in at least a part of the non-period.
- the acquisition unit 155 acquires the reception signal according to the shift clock SFTCLK that is a reference clock whose phase shift amount is adjusted with respect to the reception signal.
- the DEMUX 165 demultiplexes the reception signal acquired by the acquisition unit 155 and supplies it to the internal circuit 602 as reception data RDATA.
- the test apparatus 10 includes a control apparatus 110 and a test apparatus main body 105.
- the test apparatus body 105 includes a test unit 122, a determination unit 124, and a phase adjustment control unit 260.
- the test unit 122 is the same as the test unit 122 of FIG. 1 and functions as a test signal supply unit that supplies a test signal for testing the DUT 100 to the input terminal of the DUT 100. In this modification, the test unit 122 supplies a test signal in which a clock is superimposed on a data signal to the input terminal of the DUT 100.
- the determination unit 124 has the same function and configuration as the determination unit 124 of FIG.
- the phase adjustment control unit 260 supplies the DUT 100 with a prohibition signal that prohibits the change of the phase shift amount based on the phase comparison result during at least a part of the period when the clock is not superimposed on the test signal.
- the phase adjustment control unit 260 includes the detection unit 300 and the OR circuit 310 illustrated in FIG.
- the phase adjustment control unit 260 may supply a prohibition signal to the DUT 100 according to the prohibition signal B from the control device 110 in the same manner as the phase adjustment control unit 260 illustrated in FIGS. 1 to 5. Further, the phase adjustment control unit 260 may supply the prohibition signal C to the DUT 100 during a period in which the change of the phase shift amount is prohibited in the test sequence executed by the test unit 122. Further, the phase adjustment control unit 260 may detect that when the test signal is received and the value of the test signal does not change for a predetermined period or longer, and may supply the prohibition signal A to the DUT 100.
- each DUT 100 can prohibit the change of the phase shift amount in the connection destination DUT 100 during at least a part of the period in which the clock is not superimposed on the transmission signal. , It is possible to prevent the connected DUT 100 from being out of the phase locked state.
- the test apparatus 10 may supply the prohibition signal and the test signal to the DUT 100 via separate input terminals of the DUT 100, or may supply them through the same input terminal of the DUT 100.
- the test apparatus 10 may supply a test signal including a prohibit command for instructing the DUT 100 to prohibit the change of the phase shift amount before setting the burst state in which the value of the test signal is not changed. Good.
- the received test signal includes a prohibited command pattern, the DUT 100 transits to a CDR stop mode in which the change of the phase shift amount is prohibited.
- FIG. 7 shows a configuration of an apparatus 700 according to the third modification of the present embodiment.
- members having the same reference numerals as those in FIGS. 1 to 6 have the same functions and configurations as those in FIGS.
- the device 700 is connected to another device 700 or a device having a communication interface similar to that of the device 700, and transmits / receives data to / from a connection destination device in a time division manner via a bidirectional communication path.
- the apparatus 700 includes an internal circuit 702, an output IF circuit 622, and an input IF circuit 624.
- the internal circuit 702 is a circuit designed according to the purpose of use of the apparatus 700, and operates according to the externally received signal received via the input IF circuit 624 and the internal state of the internal circuit 702, and is necessary. In response to this, a transmission signal is transmitted to the outside via the output IF circuit 622 or the like.
- the internal circuit 702 outputs, to the output IF circuit 622, the reference clock REFCLK, the transmission data SDATA, and a transmission prohibition signal SINH for prohibiting transmission by the output IF circuit 622 during a period in which a reception signal is received from an external device. This is supplied to the IF circuit 622.
- the internal circuit 702 prohibits the change of the phase shift amount based on the phase comparison result in the input IF circuit 624 during the period of transmitting the reference clock REFCLK to the input IF circuit 624 and the transmission signal to an external device.
- the reception prohibition signal SINH is supplied to the input IF circuit 624.
- the output IF circuit 622 functions as a transmission unit that transmits a transmission signal to the outside through the terminal during a period in which the reception signal is not received from the terminal connected to the bidirectional communication path.
- the output IF circuit 622 receives the transmission prohibition signal SINH from the internal circuit 702 and stops signal output to the communication path when there is no data to be transmitted or when a reception signal is received from an external device.
- the input IF circuit 624 functions as a reception unit that receives a reception signal from the outside through the terminal during a period in which the transmission signal is not transmitted from the terminal connected to the bidirectional communication path.
- the input IF circuit 624 receives the reception inhibition signal RINH from the internal circuit 702 when there is no data to be received or when a transmission signal is transmitted to an external device.
- the input IF circuit 624 uses the reception prohibition signal RINH as the prohibition signal and prohibits the change of the phase shift amount in the input IF circuit 624.
- the device 700 described above when communicating with an external device in a time division manner via a bidirectional communication path, the phase in the input IF circuit 624 is transmitted while the output IF circuit 622 is transmitting a transmission signal. Changing the shift amount can be prohibited. Therefore, it is possible to prevent the phase shift amount from being adjusted by the transmission signal of the output IF circuit 622 during transmission by the output IF circuit 622. Note that the device 700 may arbitrate from which device the signal is transmitted to the connection destination device via the communication channel or another communication channel.
- FIG. 8 shows a configuration of the determination unit 124 according to the fourth modification of the present embodiment.
- members having the same reference numerals as those in FIG. 1 and FIG. 2 have the same functions and configurations as those in FIG. 1 and FIG. (* Comment: FIG. 8 shows a modification of the determination unit 124 of FIG. 1.
- the amount of phase shift based on the result of capturing the device signal at the half-cycle delay timing of the shift clock SFTCLK and the shift clock SFTCLK. To adjust.)
- the variable delay circuit 849 delays the shift clock SFTCLK so that the phase is different from that of the original shift clock SFTCLK.
- the variable delay circuit 849 delays the shift clock SFTCLK by less than one cycle, more preferably half a cycle, and supplies it to the acquisition unit 155b.
- the acquisition unit 155a acquires the device signal received via the comparator 140 according to the shift clock SFTCLK.
- the acquisition unit 155b acquires the device signal received via the comparator 140 according to the shift clock SFTCLK delayed by the variable delay circuit 849.
- the DEMUX 165a demultiplexes the device signal acquired by the acquisition unit 155a and supplies the demultiplexed device signal to the expected value comparison unit 170 and the phase comparison unit 810.
- the DEMUX 165b demultiplexes the device signal acquired by the acquisition unit 155b and supplies the demultiplexed device signal to the phase comparison unit 810.
- the phase comparison unit 810 compares the phase of the clock superimposed on the shift clock SFTCLK and the device signal based on the device signal demultiplexed by the DEMUX 165a and the device signal demultiplexed by the DEMUX 165b.
- FIG. 9 schematically shows the operation of the phase comparison unit 810 according to the fourth modification of the present embodiment.
- the variable delay circuit 849 delays the shift clock SFTCLK by approximately a half cycle.
- the phase comparison unit 810 adjusts the phase shift amount of the phase shift unit 250 so that the phase of the shift clock SFTCLK delayed by the variable delay circuit 849 approaches the change point of the data signal. Thereby, the phase comparison unit 810 can bring the phase of the shift clock SFTCLK closer to the approximate center of each cycle of the data signal.
- the phase comparison unit 810 performs delay when the device signal acquired by the acquisition unit 155a at the timing of the shift clock SFTCLK and the device signal acquired by the acquisition unit 155b at the timing of the delayed shift clock SFTCLK are different. It is determined that the shifted shift clock SFTCLK is located in the next cycle of the shift clock SFTCLK. Then, the phase comparison unit 810 outputs a delay signal L indicating that the shift clock SFTCLK is delayed.
- the phase comparison unit 810 obtains the device signal at the timing of the shift clock SFTCLK acquired by the acquisition unit 155a and the device signal at the timing of the delayed shift clock SFTCLK acquired by the acquisition unit 155b. Then, it is determined that the delayed shift clock SFTCLK is located in the same cycle as the shift clock SFTCLK. Then, the phase comparison unit 810 outputs an advance signal E indicating that the shift clock SFTCLK is advanced.
- the phase comparison unit 810 performs the processing described above using the device signal demultiplexed by the DEMUXs 165a and 165b. Thereby, the phase comparison unit 810 can perform phase comparison at a lower frequency than the original data signal. It should be noted that instead of the input IF circuit 624 shown in FIGS. 6 and 7, the determination unit 124 shown in FIGS. 8 to 9 is used, or the determination unit 124 is related to the input IF circuit 624 of FIG. 6 or FIG. A modified circuit as shown in FIG.
- each process such as operations, procedures, steps, and stages in the apparatus and method shown in the claims and the specification is clearly indicated as “before”, “prior”, etc.
- the output of the previous process can be implemented in any order unless it is used in the subsequent process.
- each part of the circuit can perform operations as soon as necessary data or signals are received. Can be processed in this order. Therefore, even if the operation flow in the specification is described using “first,” “next,” and the like for convenience, it does not mean that the operation flow is essential in this order.
- the acquisition unit 155 acquires the device signal or the reception signal according to the strobe signal STRB whose phase shift amount is adjusted with respect to the device signal, the multiplied clock REFCLKM, or the like.
- the device signal or the reception signal is acquired based on the shift clock SFTCLK obtained by phase-shifting the strobe signal or the multiplied clock REFCLKM by the phase shift unit 250.
- the acquisition unit 155 may relatively adjust the phase shift amount of the strobe signal STRB or the multiplied clock REFCLKM with respect to the device signal or the reception signal by delaying the device signal or the reception signal.
- the phase shift amount between the strobe signal STRB or multiplied clock REFCLKM and the device signal may be adjusted by delaying both the strobe signal STRB or multiplied clock REFCLKM and the device signal by different delay amounts.
- the phase adjustment control unit 260 masks the delay signal L and the advance signal E output from the phase comparison unit 210 or the phase comparison unit 810 with, for example, logic L, and outputs the delay and A phase comparison result indicating that there is no advance may be supplied to the digital filter 220.
- the signal on which the clock is superimposed may be a differential signal having a positive signal and a negative signal.
- the acquisition unit 155 and the acquisition units 155a and 155b may have a plurality of sets, and may be configured to acquire the signals from the comparator 140 by interleaving.
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Nonlinear Science (AREA)
- Tests Of Electronic Circuits (AREA)
- Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)
Abstract
Description
以上に示した問題は、試験装置から被試験デバイスに対してクロックが埋め込まれた信号を供給する場合、並びに、試験装置に限らない2以上の装置間でクロックエンベデッド信号を授受する場合にも生じうる。
(※コメント:図8は、図1の判定部124の変形例として記載しております。シフトクロックSFTCLKおよびシフトクロックSFTCLKの半サイクル遅れのタイミングでデバイス信号を取り込んだ結果に基づいて位相シフト量を調整します。)
Claims (16)
- 被試験デバイスを試験する試験装置であって、
当該試験装置内で生成された内部クロックと前記被試験デバイスが出力するデバイス信号に重畳されたクロックとの位相を比較する位相比較部と、
位相比較結果に基づいて、前記デバイス信号に対する前記内部クロックの位相シフト量を調整する調整部と、
前記デバイス信号に対して位相シフト量が調整された前記内部クロックに応じて前記デバイス信号を取得する取得部と、
前記デバイス信号にクロックが重畳されていない期間の少なくとも一部において、前記位相比較結果に基づく位相シフト量の変更を禁止する禁止部と、
を備える試験装置。 - 前記位相比較部は、前記内部クロックのエッジが前記デバイス信号に重畳されたクロックのエッジに対して遅れていることを示す遅れ信号、または、進んでいることを示す進み信号を前記位相比較結果として出力する請求項1に記載の試験装置。
- 前記調整部は、
前記禁止部により位相シフト量の変更が禁止されていないことを条件として、前記位相比較結果として前記遅れ信号を受け取った場合に前記調整部の位相シフト量を減少させ、前記進み信号を受け取った場合に前記調整部の位相シフト量を増加させ、
前記禁止部により位相シフト量の変更が禁止されたことを条件として、前記調整部の位相シフト量を変更しない
請求項2に記載の試験装置。 - 前記被試験デバイスを試験するための試験シーケンスを実行する試験部を更に備え、
前記禁止部は、前記試験シーケンスにおいて位相シフト量の変更が禁止された期間の間、前記調整部による位相シフト量の変更を禁止する
請求項1から3のいずれかに記載の試験装置。 - 前記取得部が取得した前記デバイス信号の値を期待値と比較する期待値比較部を更に備え、
前記禁止部は、前記期待値に基づいて前記調整部による位相シフト量の変更を禁止するか否かを判断する請求項1から4のいずれかに記載の試験装置。 - 前記禁止部は、前記取得部により取得された前記デバイス信号の値が予め指定された期間以上変化しない場合に、前記位相比較結果に基づく位相シフト量の変更を禁止する請求項1から5のいずれかに記載の試験装置。
- 前記調整部は、前記取得部により取得された前記デバイス信号の値が予め指定された期間以上変化しない場合に、前記予め指定された期間の間における位相シフト量の変更分をキャンセルする請求項1から6のいずれかに記載の試験装置。
- 前記調整部は、
前記取得部により取得された前記デバイス信号の値が変化しなくなったことを検出したことに応じて、前記デバイス信号の値が変化しなくなったことを検出するまでに調整した位相シフト量をレジスタに退避し、
前記取得部により取得された前記デバイス信号の値が予め指定された期間以上変化しない場合に、前記レジスタに退避した位相シフト量を前記デバイス信号に対する前記内部クロックの位相シフト量として再設定する
請求項1から7のいずれかに記載の試験装置。 - 被試験デバイスを試験する試験装置であって、
前記被試験デバイスは、
当該被試験デバイスの内部クロックと入力端子を介して入力される受信信号に重畳されたクロックとの位相を比較する位相比較部と、
位相比較結果に基づいて、前記受信信号に対する前記内部クロックの位相シフト量を調整する調整部と、
前記受信信号に対して位相シフト量が調整された前記内部クロックに応じて前記受信信号を取得する取得部と、
を備えており、
当該試験装置は、
前記被試験デバイスを試験するための試験信号を前記被試験デバイスの前記入力端子に供給する試験信号供給部と、
前記試験信号にクロックが重畳されていない期間の少なくとも一部において、前記位相比較結果に基づく位相シフト量の変更を禁止する禁止信号を前記被試験デバイスに供給する禁止部と、
を備える試験装置。 - 基準クロックと外部からの受信信号に重畳されたクロックとの位相を比較する位相比較部と、
位相比較の結果に基づいて、前記受信信号に対する前記基準クロックの位相シフト量を調整する調整部と、
前記受信信号に対して位相シフト量が調整された前記基準クロックに応じて前記受信信号を取得する取得部と、
前記受信信号にクロックが重畳されていない期間の少なくとも一部において、前記位相比較結果に基づく位相シフト量の変更を禁止する禁止部と、
を備える受信装置。 - 前記受信信号を入力する端子から前記受信信号を受信しない期間において、当該端子を介して外部へと送信信号を送信する送信部を更に備え、
前記禁止部は、前記送信部が前記端子を介して外部へと前記送信信号を送信する期間において、前記位相比較結果に基づく位相シフト量の変更を禁止する
請求項10に記載の受信装置。 - 受信装置に対して信号を送信する送信装置であって、
前記受信装置は、
当該受信装置の基準クロックと入力端子を介して入力される受信信号に重畳されたクロックとの位相を比較する位相比較部と、
位相比較結果に基づいて、前記受信信号に対する前記基準クロックの位相シフト量を調整する調整部と、
前記受信信号に対して位相シフト量が調整された前記基準クロックに応じて前記受信信号を取得する取得部と、
を備えており、
当該送信装置は、
前記受信装置に対して送信する送信信号を前記受信装置の前記入力端子に供給する送信部と、
前記送信信号にクロックが重畳されていない期間の少なくとも一部において、前記位相比較結果に基づく位相シフト量の変更を禁止させる禁止部と、
を備える送信装置。 - 被試験デバイスを試験する試験方法であって、
当該試験装置の内部クロックと前記被試験デバイスが出力するデバイス信号に重畳されたクロックとの位相を比較する位相比較段階と、
位相比較結果に基づいて、前記デバイス信号に対する前記内部クロックの位相シフト量を調整する調整段階と、
前記デバイス信号に対して位相シフト量が調整された前記内部クロックに応じて前記デバイス信号を取得する取得段階と、
前記デバイス信号にクロックが重畳されていない期間の少なくとも一部において、前記位相比較結果に基づく位相シフト量の変更を禁止する禁止段階と、
を備える試験方法。 - 被試験デバイスを試験する試験方法であって、
前記被試験デバイスは、
当該被試験デバイスの内部クロックと入力端子を介して入力される受信信号に重畳されたクロックとの位相を比較する位相比較部と、
位相比較結果に基づいて、前記受信信号に対する前記内部クロックの位相シフト量を調整する調整部と、
前記受信信号に対して位相シフト量が調整された前記内部クロックに応じて前記受信信号を取得する取得部と、
を備えており、
当該試験方法は、
前記被試験デバイスを試験するための試験信号を前記被試験デバイスの前記入力端子に供給する試験信号供給段階と、
前記試験信号にクロックが重畳されていない期間の少なくとも一部において、前記位相比較結果に基づく位相シフト量の変更を禁止する禁止信号を前記被試験デバイスに供給する禁止段階と、
を備える試験方法。 - 基準クロックと外部からの受信信号に重畳されたクロックとの位相を比較する位相比較段階と、
位相比較の結果に基づいて、前記受信信号に対する前記基準クロックの位相シフト量を調整する調整段階と、
前記受信信号に対して位相シフト量が調整された前記基準クロックに応じて前記受信信号を取得する取得段階と、
前記受信信号にクロックが重畳されていない期間の少なくとも一部において、前記位相比較結果に基づく位相シフト量の変更を禁止する禁止段階と、
を備える受信方法。 - 受信装置に対して信号を送信する送信方法であって、
前記受信装置は、
当該受信装置の基準クロックと入力端子を介して入力される受信信号に重畳されたクロックとの位相を比較する位相比較部と、
位相比較結果に基づいて、前記受信信号に対する前記基準クロックの位相シフト量を調整する調整部と、
前記受信信号に対して位相シフト量が調整された前記基準クロックに応じて前記受信信号を取得する取得部と、
を備えており、
当該送信方法は、
前記受信装置に対して送信する送信信号を前記受信装置の前記入力端子に供給する送信段階と、
前記送信信号にクロックが重畳されていない期間の少なくとも一部において、前記位相比較結果に基づく位相シフト量の変更を禁止させる禁止段階と、
を備える送信方法。
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020117003700A KR101214035B1 (ko) | 2008-09-04 | 2008-09-04 | 시험 장치, 송신 장치, 수신 장치, 시험 방법, 송신 방법, 및 수신 방법 |
PCT/JP2008/066005 WO2010026642A1 (ja) | 2008-09-04 | 2008-09-04 | 試験装置、送信装置、受信装置、試験方法、送信方法、および受信方法 |
JP2010527626A JP5243545B2 (ja) | 2008-09-04 | 2008-09-04 | 試験装置、送信装置、受信装置、試験方法、送信方法、および受信方法 |
TW098129279A TWI402514B (zh) | 2008-09-04 | 2009-08-31 | 對被測試元件進行測試的測試裝置、該測試裝置用的傳送裝置與接收裝置以及使用於該測試裝置的測試方法、傳送方法和接收方法 |
US13/026,155 US8643412B2 (en) | 2008-09-04 | 2011-02-11 | Test apparatus, transmission apparatus, receiving apparatus, test method, transmission method and receiving method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/JP2008/066005 WO2010026642A1 (ja) | 2008-09-04 | 2008-09-04 | 試験装置、送信装置、受信装置、試験方法、送信方法、および受信方法 |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/026,155 Continuation US8643412B2 (en) | 2008-09-04 | 2011-02-11 | Test apparatus, transmission apparatus, receiving apparatus, test method, transmission method and receiving method |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2010026642A1 true WO2010026642A1 (ja) | 2010-03-11 |
Family
ID=41796830
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2008/066005 WO2010026642A1 (ja) | 2008-09-04 | 2008-09-04 | 試験装置、送信装置、受信装置、試験方法、送信方法、および受信方法 |
Country Status (5)
Country | Link |
---|---|
US (1) | US8643412B2 (ja) |
JP (1) | JP5243545B2 (ja) |
KR (1) | KR101214035B1 (ja) |
TW (1) | TWI402514B (ja) |
WO (1) | WO2010026642A1 (ja) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120161800A1 (en) * | 2010-07-12 | 2012-06-28 | Advantest Corporation | Measurement circuit and test apparatus |
US20220321320A1 (en) * | 2021-03-31 | 2022-10-06 | Realtek Semiconductor Corp. | Linearity test system, linearity signal providing device, and linearity test method |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5537192B2 (ja) * | 2010-03-04 | 2014-07-02 | スパンション エルエルシー | 受信装置及びゲイン設定方法 |
JP2012247318A (ja) * | 2011-05-27 | 2012-12-13 | Advantest Corp | 試験装置および試験方法 |
US9203391B2 (en) | 2014-04-22 | 2015-12-01 | Qualcomm Incorporated | Pulse-width modulation data decoder |
TWI806539B (zh) * | 2022-04-08 | 2023-06-21 | 瑞昱半導體股份有限公司 | 測試系統以及測試方法 |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS581574B2 (ja) * | 1978-04-26 | 1983-01-12 | 富士通株式会社 | 多重無線中継装置 |
JPS61121547A (ja) * | 1984-11-16 | 1986-06-09 | Sony Corp | スペクトラム拡散信号受信装置 |
JPH01241247A (ja) * | 1988-03-23 | 1989-09-26 | Oki Electric Ind Co Ltd | デジタル信号検出回路 |
JPH0627217A (ja) * | 1992-07-08 | 1994-02-04 | Japan Radio Co Ltd | Gps受信機 |
JP2005077274A (ja) * | 2003-09-01 | 2005-03-24 | Toshiba Corp | 半導体集積回路装置及びそのテスト方法 |
JP2005285160A (ja) * | 2004-03-26 | 2005-10-13 | Advantest Corp | 試験装置及び試験方法 |
JP2008028628A (ja) * | 2006-07-20 | 2008-02-07 | Advantest Corp | 電気回路および試験装置 |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2015278B (en) * | 1978-02-25 | 1982-09-15 | Fujitsu Ltd | Straight-through-repeater |
GB2348327B (en) * | 1999-02-18 | 2003-02-19 | Sgs Thomson Microelectronics | Clock skew removal appartus |
JP4157144B2 (ja) * | 2005-05-09 | 2008-09-24 | 株式会社アドバンテスト | 試験装置、試験方法、および半導体デバイス |
KR100822241B1 (ko) | 2005-08-24 | 2008-04-17 | 엔이씨 일렉트로닉스 가부시키가이샤 | 인터페이스 회로 및 반도체 장치 |
WO2008020555A1 (fr) * | 2006-08-14 | 2008-02-21 | Advantest Corporation | Dispositif de test et procédé de test |
-
2008
- 2008-09-04 KR KR1020117003700A patent/KR101214035B1/ko active IP Right Grant
- 2008-09-04 JP JP2010527626A patent/JP5243545B2/ja active Active
- 2008-09-04 WO PCT/JP2008/066005 patent/WO2010026642A1/ja active Application Filing
-
2009
- 2009-08-31 TW TW098129279A patent/TWI402514B/zh active
-
2011
- 2011-02-11 US US13/026,155 patent/US8643412B2/en active Active
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS581574B2 (ja) * | 1978-04-26 | 1983-01-12 | 富士通株式会社 | 多重無線中継装置 |
JPS61121547A (ja) * | 1984-11-16 | 1986-06-09 | Sony Corp | スペクトラム拡散信号受信装置 |
JPH01241247A (ja) * | 1988-03-23 | 1989-09-26 | Oki Electric Ind Co Ltd | デジタル信号検出回路 |
JPH0627217A (ja) * | 1992-07-08 | 1994-02-04 | Japan Radio Co Ltd | Gps受信機 |
JP2005077274A (ja) * | 2003-09-01 | 2005-03-24 | Toshiba Corp | 半導体集積回路装置及びそのテスト方法 |
JP2005285160A (ja) * | 2004-03-26 | 2005-10-13 | Advantest Corp | 試験装置及び試験方法 |
JP2008028628A (ja) * | 2006-07-20 | 2008-02-07 | Advantest Corp | 電気回路および試験装置 |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120161800A1 (en) * | 2010-07-12 | 2012-06-28 | Advantest Corporation | Measurement circuit and test apparatus |
US9151801B2 (en) * | 2010-07-12 | 2015-10-06 | Advantest Corporation | Measurement circuit and test apparatus |
US20220321320A1 (en) * | 2021-03-31 | 2022-10-06 | Realtek Semiconductor Corp. | Linearity test system, linearity signal providing device, and linearity test method |
Also Published As
Publication number | Publication date |
---|---|
TW201013195A (en) | 2010-04-01 |
TWI402514B (zh) | 2013-07-21 |
US8643412B2 (en) | 2014-02-04 |
KR101214035B1 (ko) | 2012-12-20 |
US20110199134A1 (en) | 2011-08-18 |
JPWO2010026642A1 (ja) | 2012-01-26 |
JP5243545B2 (ja) | 2013-07-24 |
KR20110039354A (ko) | 2011-04-15 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5243545B2 (ja) | 試験装置、送信装置、受信装置、試験方法、送信方法、および受信方法 | |
US7737739B1 (en) | Phase step clock generator | |
KR20070027539A (ko) | 시험 장치 및 시험 방법 | |
US8090064B2 (en) | Single loop frequency and phase detection | |
KR101950320B1 (ko) | 위상 검출 회로 및 이를 이용한 동기 회로 | |
JP2008175646A (ja) | 半導体装置、半導体装置のテスト回路、及び試験方法 | |
JP2007017257A (ja) | 半導体試験装置 | |
WO2007086275A1 (ja) | 試験装置および試験方法 | |
JP5286845B2 (ja) | データリカバリ回路 | |
US7773667B2 (en) | Pseudo asynchronous serializer deserializer (SERDES) testing | |
KR20090059757A (ko) | 수신기 및 이를 포함하는 통신 시스템 | |
US8514920B2 (en) | Methods and apparatus for pseudo asynchronous testing of receive path in serializer/deserializer devices | |
JP4895551B2 (ja) | 試験装置および試験方法 | |
US9992049B1 (en) | Numerically controlled oscillator for fractional burst clock data recovery applications | |
US6704892B1 (en) | Automated clock alignment for testing processors in a bypass mode | |
JP5022359B2 (ja) | ジッタ増幅器、ジッタ増幅方法、電子デバイス、試験装置、及び試験方法 | |
JP7393079B2 (ja) | 半導体装置 | |
JP4293840B2 (ja) | 試験装置 | |
JP2009014363A (ja) | 半導体試験装置 | |
KR100911894B1 (ko) | 락킹타임을 줄일 수 있는 지연고정루프 | |
US7246018B1 (en) | Interpolator testing circuit | |
US10218491B2 (en) | Receiving circuit, integrated circuit, and receiving method | |
US5235290A (en) | Method and apparatus for smoothing out phase fluctuations in a monitored signal | |
WO2010137058A1 (ja) | 受信装置、試験装置、受信方法および試験方法 | |
US20010004246A1 (en) | Electric device, electric device testing apparatus, and electric device testing method thereof |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 08810060 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2010527626 Country of ref document: JP |
|
ENP | Entry into the national phase |
Ref document number: 20117003700 Country of ref document: KR Kind code of ref document: A |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 08810060 Country of ref document: EP Kind code of ref document: A1 |