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LeCroy AP034 Instruction Manual

Manual is about: Active Differential Probe

Summary of AP034

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    ,qvwuxfwlrq0dqxdo /h&ur\$3 $fwlyh'liihuhqwldo3ureh revision d — january 2000

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    Warranty lecroy warrants this oscilloscope accessory for normal use and operation within specifications for a period of three years from the date of shipment. Calibration after each 12 month interval is recommended to ensure performance to specification. Spare parts, replacement parts and repairs ar...

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    Ap034-om-e rev d issued: january 2000 lll &rqwhqwv table of contents overview description .................................................................................................................................. 1-1 applications .................................................................

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    Ly issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh incorrect frequency response ........................................................................................ 5-2 dc errors ....................................................................................................................

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    Ap034-om-e rev d issued: january 2000 y &rqwhqwv specifications nominal characteristics .............................................................................................................. 8-1 warranted electrical characteristics ...............................................................

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    Yl issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh blank page.

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    Ap034-om-e rev d issued: january 2000 ² 2yhuylhz 2yhuylhz description the ap034 is a wide-band, active differential probe. The probe features low noise, low input capacitance, high common mode rejection, and field effect transistor (fet) buffered inputs in the probe head. The user-selectable offset ...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh conventions used in this manual the following conventions may appear in this manual: note a note contains general information relating to the use of the product. Caution a caution contains information that should to be followed to avoid possible ...

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    Ap034-om-e rev d issued: january 2000 ² 6dihw\,qirupdwlrq 6dihw\,qirupdwlrq operator safety the ap034 active differential probe is intended to be used only with instruments that are connected to earth ground through the input bnc connector. When you are using the probe with an adpps power supply ada...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh blank page.

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    Ap034-om-e rev d issued: january 2000 ² 2shudwlrq 2shudwlrq caution the input circuits in the ap034 active differential probe incorporate components that protect the probe from damage resulting from electrostatic discharge (esd). Keep in mind that this is an active probe, and it should be handled ca...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh connected to the test circuit. The ground connection is optional. Positive voltages applied to the + input relative to the – input will deflect the oscilloscope trace toward the top of the screen. To maintain the high performance capability of th...

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    Ap034-om-e rev d issued: january 2000 ² 2shudwlrq characteristics of the input of the probe with which they were shipped. The input characteristics of the external attenuator itself do not exactly match those of the probe. Therefore, using the ÷10 and ÷20 attenuators at the same time is not recommen...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh • the larger (0.8 mm) mini clips can be used to connect to through-hole leaded components. • the offset round pins can be used for hand-held probing applications. Reposition the pins by rotating them to obtain the required spacing. Probe input lo...

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    Ap034-om-e rev d issued: january 2000 ² 2shudwlrq in most cases it is not necessary to ground the probe to the circuit under test. However, if the test circuit is isolated from earth ground, it is usually necessary to connect the probe ground to a point in the circuit. Grounding test circuits that a...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh selecting the proper range the ap034 active differential probe has a fixed gain of x1 (unity). Use of the ÷10 or ÷20 external attenuators reduces the amplitude of the input signal when it is necessary to extend the dynamic operating range of the ...

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    Ap034-om-e rev d issued: january 2000 ² 2shudwlrq when using a differential probe or amplifier, be careful to avoid exceeding the common mode range. Because the common mode signal is rejected by the differential probe, and is not displayed, changes in the amplitude of the common mode component are n...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh when the ap034 active differential probe is first connected to the oscilloscope, the following message will appear: “warning: probe offset buttons are locked.” this alerts you that offset control must be made through the oscilloscope, rather than...

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    Ap034-om-e rev d issued: january 2000 ² 2shudwlrq signal that can be viewed at any equivalent scale factor is the input differential mode range plus the offset used. See adding offset on the following page. When using the ap034 with the adpps power supply on oscilloscopes without probus interface, u...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh adding offset the ap034 active differential probe has true differential offset capability. This allows you to remove a dc bias voltage from the differential input signal while maintaining dc coupling. By using probe offset rather than the p ositi...

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    Ap034-om-e rev d issued: january 2000 ² 2shudwlrq displayed above the graticule for a few seconds after a change is made by turning the knob (refer to figure 3). In prior software versions, the channel o ffset knob adjusted the offset of the oscilloscope input rather than the probe offset. When the ...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh successful completion of the autobalance cycle. In many situations, this will be adequate to make routine measurements. Designing test fixtures for the ap034 probe often it is desirable to connect the probe directly to user- fabricated test fixtu...

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    Ap034-om-e rev d issued: january 2000 ² 5hihuhqfh,qirupdwlrq 5hihuhqfh,qirupdwlrq differential mode and common mode differential probes amplify the voltage difference that appears between the + and – inputs. This voltage is referred to as the differential mode or normal mode voltage. The voltage com...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh figure 6. Common mode and differential mode range common mode rejection ratio the ideal differential probe or differential amplifier would amplify only the differential mode voltage component and reject all of the common mode voltage component. R...

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    Ap034-om-e rev d issued: january 2000 ² 5hihuhqfh,qirupdwlrq seldom a pure sine wave. Signals with pulse wave shapes contain frequency components much higher than the repetition rate may suggest. As such, it is very difficult to predict actual performance in the application for cmrr-versus-frequency...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh blank page.

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    Ap034-om-e rev d issued: january 2000 ² &duhdqg0dlqwhqdqfh &duhdqg0dlqwhqdqfh cleaning the exterior of the probe and cable should be cleaned only using a soft cloth moistened with water or isopropyl alcohol. Abrasive agents, strong detergents, or other solvents may damage the probe. Always ensure th...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh 2. Set the oscilloscope calibrator to output a 100-mv, 1-khz square wave. Using the flex lead set, connect the probe + input to the calibrator output signal, leave the – input open. Set the oscilloscope to 50 mv/div and 500 µ s/div. Is the displa...

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    Ap034-om-e rev d issued: january 2000 ² &duhdqg0dlqwhqdqfh 2. Connect the probe to another oscilloscope. If the probe now measures properly, the problem may be in the oscilloscope. 3. If the probe behaves as if it is ac-coupled at high frequency, check for an open input connection. 4. Poor frequency...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh the calibrator, the problem may be caused by large mismatches in the source impedance. Try connecting both inputs to one of the input signals in the test circuit, then the other. If the common mode signal disappears, try probing lower impedance p...

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    Ap034-om-e rev d issued: january 2000 ² &duhdqg0dlqwhqdqfh 6. Mark the outside of the box with the shipping address given to you by the lecroy representative; be sure to add the following: • attn: representative> • fragile 7. Insure the item for the replacement cost of the probe. 8. Ship the package...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh figure 7. Replceable parts 13 14 12 11 2 5 8 6 7 4 9 10 1 3.

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    Ap034-om-e rev d issued: january 2000 ² &duhdqg0dlqwhqdqfh reference lecroy part number description rev qty. 1 529-304-001 plastic probe tip housing top a 1 2 377-000-007 lecroy ap034 probe tip label a 1 3 529-304-003 plastic probe tip housing end a 1 4 529-304-002 plastic probe tip housing bottom a...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh matching procedure for ÷ 10 plug-on external attenuator the ÷ 10 and ÷ 20 plug-on attenuators provided as standard accessories with the ap034 are calibrated to match the specific probe they are shipped with. Individual probes will have small vari...

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    Ap034-om-e rev d issued: january 2000 ² &duhdqg0dlqwhqdqfh from the output to provide the trigger signal for the test oscilloscope. Interconnect cable this is for connecting the output of the signal source to the probe. A bnc cable and a pair of small alligator clips or “lead grabber” adapter (pomon...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh 6. Using the alligator clips on the end of the interconnect cable, connect the signal source ground to the square pin on the attenuator adapter’s “–“ input. Attach the signal output to the square pin on the attenuator adapter’s “+” input. 7. Turn...

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    Ap034-om-e rev d issued: january 2000 ² &duhdqg0dlqwhqdqfh figure 8. Attenuator adjustment locations 12. Move the connections on the interconnect cable so the signal generator ground is connected to the square pin inserted in the ground connector of the attenuator adapter. Connect the signal generat...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh during the transition of the displayed waveform. It may not be possible to completely eliminate the overshoot. As with the +lf comp adjustment, the added capacitance of the adjustment tool may change the amplitude of the waveform when it is inser...

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    Ap034-om-e rev d issued: january 2000 ² 3huirupdqfh9hulilfdwlrq 3huirupdqfh9hulilfdwlrq this procedure can be used to verify the warranted characteristics of the ap034 active differential probe. The recommended calibration interval for the model ap034 active differential probe is one year. The compl...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh table 3. List of required equipment description minimum requirements test equipment examples wide band oscilloscope 1 minimum 1 ghz bandwidth 2 mv to 5 v scale factors probus interface equipped 2% vertical accuracy lecroy lc584a digital multimete...

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    Ap034-om-e rev d issued: january 2000 ² 3huirupdqfh9hulilfdwlrq whuplqdwlrq ri wkh rvfloorvfrsh pxvw eh vhw wr dqg wkh offset or position must remain at center screen. Preliminary procedure 1. Connect the ap034 active differential probe to the female end of the probus extension cable. Connect the ma...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh a. Check gain accuracy 1. From the oscilloscope display, select the channel that the ap034 is connected to (channel 1), then select the “coupling” menu. Set the coupling to dc 1 m Ω . (if the only choice available is ac 1 m Ω , remove the plug-on...

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    Ap034-om-e rev d issued: january 2000 ² 3huirupdqfh9hulilfdwlrq 12. Connect the free end of the output cable from the function generator to the differential drive no termination connector of the ap033/ap034 calibration fixture. 13. After the dmm reading has stabilized, record the measured output amp...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh termination connector. Make sure that the probe is fully engaged in the fixture. 3. Set the oscilloscope to display channel 1. In the oscilloscope channel 1 “coupling” menu, set coupling to dc 1 m Ω , and global bwl to off. Autobalance the ap034 ...

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    Ap034-om-e rev d issued: january 2000 ² 3huirupdqfh9hulilfdwlrq 12. Set the oscilloscope to display channel 1 only, set the trigger source to channel 1, and set the channel 1 vertical scale factor as needed to measure the amplitude of the displayed waveform. Adjust the trigger level as necessary for...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh c. Check low frequency cmrr note because greater amplitudes are required to measure the higher cmrr specifications at low frequencies, the function generator will be used in place of the high-frequency sine wave generator for the low frequency cm...

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    Ap034-om-e rev d issued: january 2000 ² 3huirupdqfh9hulilfdwlrq 4. Set the sine wave generator frequency to 70 hz, and the output amplitude to 20 v p-p , (4 divisions on the oscilloscope). If necessary, adjust the trigger level for a stable display. 5. Set the oscilloscope to display channel 1, but ...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh 14. Record the displayed “common mode signal at 1 mhz” to two-digit resolution in the test record. 15. Calculate the “common mode rejection ratio (cmrr) at 1 mhz” by dividing 8000 mv by the measured common mode signal recorded in step c-14. Recor...

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    Ap034-om-e rev d issued: january 2000 ² 3huirupdqfh9hulilfdwlrq ap034 performance verification test record this record can be used to record the results of measurements made during the performance verification of the ap034 active differential probe. Photocopy this page and record the results on the ...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh ap034 performance verification test record step description intermediate data test result gain accuracy a-7 sine wave generator output voltage ________________ mv a-13 probe output voltage ________________ mv a-15 gain error (test limit 2%) _____...

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    Ap034-om-e rev d issued: january 2000 ² $gmxvwphqw3urfhgxuh $gmxvwphqw3urfhgxuh introduction you can use this procedure to adjust the ap034 active differential probe to meet the warranted specifications. This procedure should only be performed if the instrument fails the performance verification tes...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh grounding wrist strap and follow standard static control procedures. The probe tip housing provides physical rigidity to the input pins of the probe. When the covers are removed, observe extra caution to avoid breaking the probe tip receptacles w...

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    Ap034-om-e rev d issued: january 2000 ² $gmxvwphqw3urfhgxuh table 4. Test equipment and accessories description minimum specifications test equipment examples wide band oscilloscope * 500 mhz bandwidth 2 mv to 200 mv vertical scale factors probus interface equipped* 2% vertical accuracy lecroy lt342...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh table 4. Test equipment and accessories description minimum specifications test equipment examples bnc coaxial cable (2 required) male-male bnc, approx. 1 m pomona 5697-36 bnc tee adapter female-male-female pomona 3285 banana plug adapter (2 requ...

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    Ap034-om-e rev d issued: january 2000 ² $gmxvwphqw3urfhgxuh gently slide the larger cover off by pulling it away from the probe tip end. 4. Connect the ap034 active differential probe output to the female end of the probus extension cable. Be careful to align the probus pins with the corresponding c...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh components. Remove or redirect any fans that may be blowing air currents over the probe tip during adjustment. Note correct operation of the ap034 active differential probe controls requires software version 8.1.0 or higher. You can find out the ...

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    Ap034-om-e rev d issued: january 2000 ² $gmxvwphqw3urfhgxuh procedure a. Adjust coarse dc balance (r226) 1. If necessary, set the probe offset to 0.000 v by rotating the o ffset knob in the channel section of the oscilloscope. 2. Insert the two-pin shorting plug into the socket on the logic board. U...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh figure 10. Amplifier board adjustment locations b. Adjust fine dc balance (r304) 1. Remove the shorting plug from the logic board. 2. Reinsert the shorting plug into the two holes near the end of the logic board. (figure 9.) 3. Reenter cal mode b...

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    Ap034-om-e rev d issued: january 2000 ² $gmxvwphqw3urfhgxuh 7. Using a low capacitance screwdriver, adjust fine dc balance (r304) until the ÷ 10 effective gain indicator lights (figure 11). Figure 11. ÷ 11 effective gain indicator 8. Disconnect the bnc cable from the short connector. Remove the shor...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh 5. Set the oscilloscope as follows: display: channel 2 channel 1 volts/div: 2 mv/div channel 2 volts/div: 5 v/div channel 2 coupling: '&0 channel 3 volts/div: 2 mv/div channel 3 coupling: ac 1m trigger on: ext10 cplg ext10: dc time/div: 10 ms/div...

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    Ap034-om-e rev d issued: january 2000 ² $gmxvwphqw3urfhgxuh figure 12. Probe tip adjustment locations 12. Remove the bnc cable from the output of the function generator and the calibration fixture. Leave the bnc cable from the sync output to the oscilloscope external trigger input in place. D. Adjus...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh 5. Connect the other end of the cable to the dmm input, making sure that the plug corresponding to the bnc shield (marked “ground”) is connected to the lo or com input. 6. Set the dc voltage source to read as close as possible to +1.600 v on the ...

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    Ap034-om-e rev d issued: january 2000 ² $gmxvwphqw3urfhgxuh 18. Again, remove the dual banana plug adapter from the output of the dc voltage source and reconnect it, with the pins reversed. The plug corresponding to the bnc shield (marked “ground”) should now be connected to the – or common output c...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh 6. Record the dmm reading. Be careful not to alter the output amplitude of the generator after the measured value has been recorded 7. Remove the banana plug adapter and connect the free end of the cable to the differential drive no termination c...

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    Ap034-om-e rev d issued: january 2000 ² $gmxvwphqw3urfhgxuh fixture to the probe tip. Press the probe into the fixture to fully engage the pins. 5. Set the oscilloscope display to channel 1, vertical scale factor to 50 mv/div and the horizontal scale to 1 µ s/div. Set the trigger source to channel 1...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh 5. Adjust attenuator cmrr (capacitor c18a) for minimum amplitude shift of the displayed waveform at the trigger point in time. See figure 10 for adjustment location. 6. Leave the setup connected for the next step. H. Assemble probe and amplifier ...

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    Ap034-om-e rev d issued: january 2000 ² $gmxvwphqw3urfhgxuh i. Attenuator matching and final check 1. Repeat the performance verification procedure to ensure compliance with the warranted specifications. 2. Perform the attenuator matching procedure listed on page 5-8. Apply calibration seals in acco...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh blank page.

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    Ap034-om-e rev d issued: january 2000 ² 6shflilfdwlrqv 6shflilfdwlrqv the following specifications are valid for model ap034 probes after the probe has reached operating temperature. This takes 20 minutes with power applied, in an environment with stable ambient temperature. The probe must be operat...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh warranted electrical characteristics warranted characteristics are parameters with guaranteed performance. Unless otherwise noted, tests are provided in the performance verification procedure for all warranted specifications. Lf gain accuracy: 2%...

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    Ap034-om-e rev d issued: january 2000 ² 6shflilfdwlrqv typical electrical characteristics typical characteristics are parameters with no guaranteed performance. Tests for typical characteristics are not provided in the performance verification procedure. Bandwidth, probe only (–3 db): dc to 1 ghz ou...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh figure 13. Typical cmrr graphs.

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    Ap034-om-e rev d issued: january 2000 ² 6shflilfdwlrqv general characteristics temperature: 0 to 50 °c (operating) –40 to 75 °c (storage) input connectors: compatible with 0.025 in. (0.635 mm) square pins 0.036 in. (0.91 mm) maximum diameter (for round pins) power requirements: powered from oscillos...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh compliance and certifications ec declaration of conformity: conforms to emc directive 89/335/eec for electromagnetic emission and immunity requirements. En 55011:1997: the probe has been tested to verify compliance with this standard, class b for...

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    Ap034-om-e rev d issued: january 2000 ² 6shflilfdwlrqv standard accessories hard case ÷ 10 plug-on attenuator ÷ 20 plug-on attenuator plug-on ac coupler probe connection accessory kit: flex lead set (1) mini clip, 0.8 mm (3) mini clip, 0.5 mm (2) ground lead (1) offset pins, round (4) square pin hea...

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    ² issued: january 2000 ap034-om-e rev d $3$fwlyh3ureh blank page.