1692 Digibridge 电路图.pdf

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1、1692 RLC Digibridge Instruction Manual Form 1692-0120-00/C2 QuadTech, Inc., 1993 5 Clock Tower Place, 210 East Maynard, Massachusetts, U.S.A. 01754 October, 2000 Telephone 978-461-2100 Sales 800-253-1230 Facimile 978-461-4295 Website The material in this manual is for informational purposes only and

2、 is subject to change, without notice. QuadTech assumes no responsibility for any error or for consequential damages that may result from the misinterpretation of any procedures in this publication. Contents Specifications Warranty Introduction -Section 1 Installation -Section 2 Operation -Section 3

3、 Theory -Section 4 Service and Maintenance -Section 5 Parts Lists and Diagrams -Section 6 RadioFans.CN 收音机爱 好者资料库 These two supplementary pages contain infonnation of improvements or modifications not documented in the current manual. All references to GenRad in the manual now apply to QuadTech, Inc

4、. Page iv -Table of Contents (Parts Lists and Diagrams -Section 6) Power supply assembly, board layout and schematic (pages 6-13 Bins 0 thru 9 (10 lines) ACQ OVER; (1 line) indicates end of data acquistion (component can be moved without affecting measurement results) EOT; (1 line) indicates end of

5、test and that valid bin nwnbers for sorting are available. Outputs are active low (open collector drivers rated at 30 V x. Each will sink 16 mA at 0.4 V. External power and pull-up resistors are required). Handler Inputs: Start; (1 line) To initiate measurement. Input is active low (0V V1 0.4V) and

6、(+2.5V Vh +5V) viii ENVIRONMENT Operating; 0 to 50 degrees C, 1 us, and (if START is not debounced) a-c the settling time or programmed delay. For single measurements, the DUT can be disconnected after e. The selected BIN line goes low at f; the other BIN lines stay high. For AVERAGE measurement rou

7、tines, AOQ OVER goes low (e) at the end of the last measurement . 2.7.2 Timing Figure 2-3. Refer to the accompanying figure for timing guidelines. Notice that START must have a duration of 1 us (minimum) in each state (high and low). If START is provided by a mechanical switch without debounce circu

8、itry, the Digibridge will make many false starts; if START does riot settle down (low) within the default settling time after the first transition to high, the measurement time may increase substantially. Measurement starts at time d, which is essentially the same as time b or c; measurement is comp

9、leted at g. (The START signals are expanded for clarity.) Interval a-e, during which the DUT must remain connected for data acquisition, is considerably shorter than the total measurement time a-g. The DUT can be changed after e (indexing on ACQ, to save time) or after g (indexing on EOT, for a simp

10、ler test setup), as explained below. After the calculation interval e-f, measurement results are available for sorting, i.e., one of the BIN lines goes low. A few micro-seconds later, EOT goes low (can be used to set a latch holding the bin assignment). ACQ OVER, the selected BIN line, and EOT then

11、stays low until the next start command. The time required for measurement depends on test condition, and operating selections. Interval a-e can be less than 15 ms; the cycle a-g can be less than 40 ms; refer to paragraph 3.5 for details. Set up the handler either of two ways: indexing on EOT or inde

12、xing on ACQ, as follows. The handler must supply a signal (here called start next measurement) when it has completed connection of the DUT to the test fixture. 2-6 INSTALLATION Indexing on EOT. Set up the handler to respond to the EOT signal from the Digibridge, which occurs at the end of test, when

13、 the bin assignment is available for sorting. Set up the Digibridge to receive its START signal from the handlers start next measurement signal. This setup is simpler than the one below. NOTE The Digibridge requires that a non-zero value be entered for nominal value to enable generation of the EOT s

14、ignal and indication by the GO/NO-GO lights; see paragraphs 3.8.3,3.8.4. Indexing on ACQ. Set up the handler to respond to the ACQ OVER signal from the Digibridge, which occurs when the data acquisition is complete. The handler can then remove the DUT from the test fixture and replace it with anothe

15、r DUT, while the Digibridge is calculating the result. In addition, set up an interface that provides a START signal to the Digibridge by logical combination of the, EOT signal from the Digibridge AND the start next measurement signal from the handler. Indexing on ACQ results in higher measurement r

16、ate than indexing on EOT. Be sure the TALK switch is set to TALK ONLY, if the IEEE-488 bus is not used. Figure 2-4. Block diagram of a generalized system interconnected by the 16-signalline bus specified in the IEEE Standard 488. Reprinted from Electronics, November 14, 1974; copyright McGraw-Hill,

17、Inc., 1974. INSTALLATION 2-7 2.8 IEEE-488 INTERFACE (OPTION) 2.8.1 Purpose Figure 2-4. If you have the 1658-9620 interface option, you can connect this instrument to a printer or into a system (containing a number of devices such as instruments, apparatus, peripheral devices, and generally a control

18、ler or computer) in which each component meets IEEE Standard 488-1978, Standard Digital Interface for Programmable Instrumentation. A complete understanding of this Standard (about 80 pages) is necessary to understand in detail the purposes of the signals at the IEEE-488 INTERFACE connector on the r

19、ear panel of this instrument. NOTE For copies of the Standard, order IEEE Std 488- 1978, IEEE Standard Digital Interface for Programmable Instrumentation, from IEEE Service Center, Department PB-8, 445 Hoes Lane, Piscataway, N. J. 08854. To make connection to a single device like a printer, use a IE

20、EE-488 cable, which fits the rear-panel connector labeled IEEE-488 INTERFACE. For larger systems, each device is connected to a system bus, in parallel, usually by the use of several stack able cables. Refer to the figure for a diagram of a hypothetical system. A full set of connections is 24 (16 si

21、gnals plus shield and ground returns), as tabulated below and also in the Standard. Suitable cables, stack able at each end, are available from Component Manufacturing Service, Inc., West Bridgewater, MA 02379, U.S.A. (Their part number 2024/1 is for a 1- meter-Iong cable.) This instrument will func

22、tion as either a TALK/LISTEN or a TALK ONLY device in the system, depending on the position of the TALK switch. TALK/LISTEN denotes full programmability and is suited for use in a system that has a controller or computer to manage the data now. The handshake routine assures that the active talker pr

23、oceeds slowly enough for the slowest listener that is active, but is not limited by any inactive (unaddressed) listener. TALK ONLY is suited to a simpler system -e.g. Digibridge and printer -with no controller and no other talker. Either mode provides measurement results to the active listeners in t

24、he system. 2-8 INSTALLATION Figure 2-5. The handshake process, illustrated by timing diagrams of the pertinent signals for a system with one talker and several listeners. For details, refer to the standard. 2.8.2 Interlace Functions Figure 2-5. The following functions are implemented. Refer to the S

25、tandard for an explanation of the function subsets, represented by the identifications below. For example, T5 represents the most complete set of talker capabilities, whereas PP0 means the absence of a capability. SH1, source handshake (talker) AH1, acceptor handshake (listener) T5, talker (full cap

26、ability, serial poll) L4, listener (but not listen-only) SR1, request by device for service from controller RL2, remote control (no local lockout, no return-to-Iocal switch) PP0, no parallel poll DC0, no device clear DT1, device trigger (typically starts measurement) C0, no controller functions. The

27、 handshake cycle is the process whereby digital signals effect the transfer of each data byte by means of status and control signals. The cycle assures, for example, that the data byte has settled and all listeners are ready before the talker signals data valid. Similarly, it assures that all listen

28、ers have accepted the byte before the talker signals data not valid and makes the transition to another byte. Three signal lines are involved, in addition to the 8 that convey the byte itself. Refer to the accompanying figure. INSTALLATION 2-9 2.8.3 Signal Identification Refer to Table 2-2 for a key

29、 to signal names, functions, and pin numbers. Further expJanation is found in the Standard. The first three signals listed take part in the handshake routine, used for any multiline message via the data bus; the next five are used to manage the flow of information; the last eight constitute the mult

30、iline message data bus. 2-10 INSTALLATION Table 2-2 (continued) IEEE-488 INTERFACE KEY * END is typically sent concurrently with the delimiter linefeed character that terminates the string(s) of data output from the Digibridge (1, 2, or 3 lines; see para 2.8.4). *IDY is not implemented in this Digib

31、ridge. 2.8.4 Codes and Addresses General- The device-dependent messages, such as instrument programming commands and measurement data (which the digital interface exists to facilitate), have to be coded in a way that is compatible between talkers and listeners. They have to use the same language. Ad

32、dresses have to be assigned, except in the case of a single talker only with one or more listeners always listening. The Standard sets ground rules for these codes and addresses. In this instrument, codes for input and output data have been chosen in accordance with the rules. The address (for both

33、talker and listener functions) is user selectable, as explained below. Instrument Program Commands. The set of commands used in remote programming is an input data code 1 which the instrument will respond as a talker/listener, after being set to a remote code and addressed to listen to device-depend

34、ent command strings. The set includes all of the keyboard functions except switching external bias ON/OFF and full recalibration, which are not remotely programmable. Refer to paragraph 3.11.3 for a table of the commands used in programming Address. The initial setting of address, provided by the fa

35、ctory, is binary 00011. Consequently, the talk address command (MTA) is C in ASCII code and, similarly, the listen-address command (MLA) is #- If a different address pair is desired, set it manually using the following procedure. INSTJLLATION 2-11 WARNING Because of shock hazard and presence of elec

36、tronic devices subject to damage by static electricity (conveyed by hands or tools), disassembly is strictly a service procedure. a. Take the Digibridge to a qualified electronic technician who has the necessary equipment for minor disassembly and adjustment. Remove the interface option assembly, as

37、 described in the 1692 Digibridge Service instructions. (There is no need to remove the top cover first.) b. Set the switches in DIP switch assembly S2 to the desired address, which is a 5-bit binary number. (See below. ) c. Replace the interface option assembly in its former place. Notice that S2 i

38、s located at the end of the interface option board, about 3 cm (1 in.) from the TALK switch S1. If S2 is covered, lift the cover off, exposing the DIP switch, which has 6 tiny switches, numbered 1 thru 6. To enter logical 1 s, depress the side of each switch nearest the end of the board (switch open

39、). To enter logical 0s, depress the other side of the switch (switch closed). The address is read from 5 to 1 (not using 6). Thus, for example, to set up the address 00011, enter 0s at positions 5, 4, 3; enter 1 s at positions 2, 1. (This makes the talk address C and the listen address #.) Strictly

40、speaking, the address includes more; S2 determines only the device-dependent bits of the address. You cannot choose talk and listen addresses separately, only as a pair. The list of possible pairs is shown in Table 2-3. 2-12 INSTALLATION Table 2-3 ADDRESS PAIRS AND SETTINGS FOR SWITCH S2 Do NJT set

41、the switch to 11111, because a talk address of - would be confused with an un talk conmand, and a listen address of ?, with an un listen conmand.(ASCII code for - is 1 011 III and for ? is 0 III 111.) INSTALLATION 2-13 In the above example, the remote message codes MLA and MTA are X01000ll and XI000

42、0l1, respectively. Thus the listen address and the talk address are distinguished, although they contain the same set of device dependent bits, which you set into S2. Data Output. Data (results of measurements) are provided on the DI01.DI07 lines as serial strings of characters. Each character is a

43、byte, coded according to the 7-bit ASCII code, as explained above. The alphanumeric characters used are appropriate to the data, for convenience in reading printouts. The character strings are always provided in the same sequence as that tabulated in paragraph 3.11.3; for example: RLC value, QDR val

44、ue, bin number -if all 3 were selected (by the X7 command). The carriage-return and line-feed characters at the end of each string provide a printer (for example) with the basic commands to print each string on a separate line. For example, if the measurement was 0.54321 uF (1 kHz, range 4 held), th

45、e character string for RLC value is: U(space)C(space)uF(2 spaces )0.54321( CR)(LF). If the D measurement was .001, the character string for QD value is: (2 spaces)D(5 spaces)00.0010(CR)(LF). If the measurement falls into bin 9, the character string for bin number is: F( space )BIN( 2 spaces )9( CR )

46、(LF). The character string for RLC value has the length of 17 characters; for QD value, 17 characters; for bin number, 10 characters -including spaces, carriage-return, and line-feed characters. Refer to the format tables in paragraph 3.11.2 for details. 2.9 ENVIRONMENT The Digibridge can be operate

47、d in nearly any environment that is comfortable for the operator. Keep the instrument and all connections to the parts under test away from electromagnetic fields that may interfere with measurements. Refer to the Specifications at the front of this manual for temperature and humidity tolerances. To

48、 safeguard the instrument during storage or shipment, use protective packaging. Service personnel refer to Section 5 When the Digibridge is mounted in a rack or other enclosed location, make sure that the ambient temperature inside the rack does not exceed the limits specified under Environment in the Specifications at the front of this manual, and that air can circulate freely past all air inlet and outlet vents. 2-14 INSTALLATION 3.1 BASIC PROCEDURE. 3-1 3.2 CONNECTING THE DUT . 3-4 3 .3 MEASUREMENT PARAMETERS, RESULTS DISPLAYS, OUTPUTS 3-13 3.4 PRINCIPAL TEST CONDITIONS . 3-2