1. Manuals
  2. Brands
  3. Highland Manuals
  4. Pulse Generator
  5. P400
  6. Technical manual

Highland P400 Technical Manual

Benchtop digital delay/pulse generator
Hide thumbs
Table of Contents

Advertisement

Quick Links

Download this manual
HIGHLAND TECHNOLOGY
Model P400
Benchtop Digital Delay/
Pulse Generator
Technical Manual

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the P400 and is the answer not in the manual?

Questions and answers

Summary of Contents for Highland P400

  • Page 1 HIGHLAND TECHNOLOGY Model P400 Benchtop Digital Delay/ Pulse Generator Technical Manual...
  • Page 2 The P400 has finite failure rates associated with its hardware, firmware, design, and documentation. Do not use the product in applications where a failure or defect in the instrument may result in injury, loss of life, or property damage.

  • Page 3: Table Of Contents

    Table of Contents Introduction and Scope ................1 Scope ..................... 1 Introduction ..................... 1 Operating And Safety Precautions ............2 Specifications ..................3 Theory of Operation ................7 Basic Timing ................... 7 Block Diagram and Basic Functions ............8 Quick Start: Pulse-Train Example ............11 Operating Instructions................
  • Page 4 Remote Error Codes ................48 Command Strings ................. 50 RS-232 Interface .................. 51 Ethernet Interface ................. 52 7.5.1 DHCP-Mode Configuration ............52 7.5.2 Static-Mode Configuration ............53 7.5.3 Connecting the P400 to the Network ........53 Versions, Options, and Accessories ........... 55 Index....................... 56...
  • Page 5 Figure 19. 10 V Pulse with High-Impedance Termination ........30 Figure 20. RS-232 Connector Pin-Out ..............51 Table of Tables Table 1. P400 Specifications ................3 Table 2. Front-Panel Features ................15 Table 3. Back-Panel Features ................16 Table 4. P 400 Commands ................. 33 Table 5.

  • Page 6: Introduction And Scope

    This document is the technical manual for the Highland Technology Model P400 benchtop digital delay generator, Highland part number 23A400-1. 1.2 Introduction The P400 is a versatile, four-channel digital delay and pulse generator. The unit supports five trigger sources. Internal direct digital synthesis (DDS) rate generator...

  • Page 7: Operating And Safety Precautions

    During powerup and powerdown, it is possible that the P400 may create undesired outputs at the T0, A, B, C, D, or GATE outputs. Do not use the P400 in situations where such outputs may result in compromises in personnel safety or equipment...

  • Page 8: Specifications

    Specifications Table 1. P400 Specifications FUNCTION Four-channel digital delay and pulse generator Independently programmable delay/pulse width/polarity/high level/low level on all four delay outputs A, B, C, and D CHANNELS Four outputs of programmable delay, pulse width, polarity, and voltage levels...
  • Page 9 DELAY RANGE 999.999999999999 seconds, delay or width of A, B, C, D outputs, total delay + width not to exceed 999.999999999999 seconds A to D timings are relative to T0 rising edge DELAY ACCURACY T0, rises 25 ns ± 500 ps after trigger A to D outputs, ±...
  • Page 10 INDICATORS 20-character by 4-line, alphanumeric display LEDs indicate selected channel, activity, triggers, communications, and errors TIMEBASE Standard TCXO: Initial calibration ±0.25 PPM Drift <2 PPM/year Temperature coefficient below 50 ppb/° C Jitter below 2 ns per second of delay Optional OCXO: Initial calibration ±0.1 PPM Drift <1 PPM/year Temperature coefficient below 3.6 ppb/°...
  • Page 11 OPTIONS Rear-panel transformer-isolated 5 to 50 V programmable high-voltage pulse outputs 10BASE-T Ethernet Ovenized oscillator timebase (OCXO) Single/dual rackmount adaptors OEM versions CONFORMANCE Designed to meet UL/FCC/CE requirements...

  • Page 12: Theory Of Operation

    Theory of Operation 3.1 Basic Timing Figure 1 depicts the basic P400 timing cycle. Figure 1. Example Timing Diagram A timing cycle begins 25 ns after a trigger pulse is received. T0 is asserted, transitioning from VL (programmed low level) to VH (programmed high level), indicating the start of the timing cycle.

  • Page 13: Block Diagram And Basic Functions

    VL. When the EOD interval expires the P400 is ready to accept new trigger pulses. If the last programmed edge is programmed to be k ns after T0, the P400 will accept triggers separated by (k + 60) ns up to the specified 10 MHz max. For very short programmed delays, the P400 will typically externally trigger above 13 MHz.
  • Page 14 Each driver has programmable polarity, and high and low voltage levels. MICROPROCESSOR SYSTEM An internal 32-bit microprocessor subsystem manages the P400. It interacts with the front-panel controls and displays and the external RS-232 and Ethernet interfaces.
  • Page 15 POWER SUPPLIES Voltage regulators generate the required internal voltages from the 24 VDC input on the back panel. These regulators are typically powered by the external, AC-powered, universal-input, switching power supply furnished with each unit.

  • Page 16: Quick Start: Pulse-Train Example

    C, and D produce sequential 100 microsecond positive pulses, with baselines of 0 volts and pulse height +4 volts into a high-impedance load. Connect an oscilloscope to the P400, with the T0 pulse applied to scope Channel 1, and trigger on the rising edge of this signal.

  • Page 17: Figure 3. Pulse-Train Example Timing

    Note that, if you change pulse delay or width such as to make the trailing edge of the pulse exceed 500 µs after trigger, the T0 pulse width will extend to track the Channel A falling edge, demonstrating that the P400 timing cycle runs until all channels are done.
  • Page 18 2 KHz, the P400 will begin missing triggers, and the "RATE" LED will illuminate, because the unit is receiving triggers before the previous timing cycle is completed. Push the HELP button, then scroll through the Help text using the spinner knob.

  • Page 19: Operating Instructions

    Operating Instructions 5.1 Front- and Rear-Panel Overview The front panel is shown in Figure 4 and described in Table 2. RATE REMOTE HIGHLAND TECHNOLOGY MODEL P400 DIGITAL DELAY GENERATOR ENTER milli micro nano pico STOP START STORE RECALL HELP GATE...

  • Page 20: Table 2. Front-Panel Features

    These identify engineering unit positions in time displays START and STOP Keys Start and stop triggering or manually trigger a delay, indicated by the adjacent red/green LED The P400 always powers up in the STOP state. Activity LEDs These indicators light when the associated function is active...

  • Page 21: Figure 5. Rear Panel

    DDS Output Sine wave output from the internal DDS frequency synthesizer Line Trigger Input 6 to 24 VAC input for triggering the P400 synchronous to the AC line RS-232 DB9 Connector Provides for remote serial control Location for Ethernet option connector if installed Location for optional outputs;...

  • Page 22: Help Mode

    5.2 Help Mode The Help mode displays operating instructions for the P400. To access Help, press the HELP key, shown in Figure 4. To exit the Help menu press the HELP key a second time. The initial lines of the help page explain further the use of the help facility.

  • Page 23: Gate Menu

    4. Gate is an input as in case 3, but is active-low. The GATE led lights if the gate logic is in its trigger-enable condition, so is always on in modes 1 and 2. If it is off, the P400 cannot be triggered.

  • Page 24: Trigger Menu

    When internal trigger mode is selected, the P400 is triggered by the internal DDS generator at the rate shown in Line 4, FRQ. Line 5, PER, is set by the P400 to display the period corresponding to the trigger frequency in Line 4.

  • Page 25: Channel T0 Menu

    Line 8 of the menu, and M is set on Line 9. For example, if BURST PULSES (N) is set to 4 and OF TRIGGERS (M) is set to 20 then, if the P400 is triggered at a constant rate, the output would appear to be a burst of four pulses followed by a gap corresponding to 16 missed triggers.

  • Page 26: Channel A Through D Menus

    50 Ω termination is used, output levels will be one-half those shown. For example, to produce ECL levels with an external 50 Ω termination to ground, set VH to –1.6 V and VL to –4.0 V. The P400 output should not swing more than 5 volts while driving high- impedance loads (see Section 6).

  • Page 27: Auxiliary Menu

    T0. Negative time settings are only meaningful if the channel is set relative to another channel (A – D). The P400 does not permit circular or illogical timings and dependencies. 5.8 Auxiliary Menu Set by user...

  • Page 28: Store And Recall Menus

    Line 16, the input buffer, displays the last incoming 20 characters, and Line 17, the output buffer, displays the first 20 reply characters. Line 16 is cleared when a serial command is processed. See Chapter 7 for information on programming the P400 remote features. 5.9 Store and Recall Menus Set by user...

  • Page 29: Figure 12. Recall Menu

    Erase a stored configuration by selecting the memory location and pressing the CLR → key. The P400 will display a wait screen for approximately three seconds as the configuration is erased. It is not necessary to erase a memory location before storing a new configuration.

  • Page 30: Power-Up States

    If you do not want to keep the new configuration, press the RECALL key to return to the Recall menu, then press the CLR → key to restore the P400 to its previous state. 5.10 Power-Up States Press the POWER button to turn the P400 on or off. The P400 starts in the last configuration used before power down.

  • Page 31: Figure 13. High Voltage Option Block Diagram

    Figure 13. High Voltage Output Equivalent Circuit Because the HV outputs can furnish very high peak power (all five channels deliver 250 watts simultaneously at 50 volts out) the duty cycle and pulse widths are inherently limited. Pulse widths are also limited by transformer core saturation.

  • Page 32: Figure 15. Duty Cycle

    DUTY CYCLE VS. OUTPUT VOLTAGE 10.00% 9.00% 8.00% 7.00% 6.00% 5.00% 4.00% 3.00% 2.00% 1.00% 0.00% OUTPUT VOLTAGE Figure 15. Duty Cycle Figure 14 and Figure 15 show the maximum available pulse width and duty cycle available from any one channel; channels are independent so these limits do not depend on other channels.

  • Page 33: Figure 17. Typical 50-Volt Output Pulse

    Outputs are positive pulses, but are isolated so can be inverted by external wiring. Cleanest negative pulses will result from adding a coaxial crossover (swapping inner and outer conductors) some distance from either the P400 or the load. If any ringing is observed, slipping a ferrite core or EMI suppressor over the...

  • Page 34: Typical Performance

    500 MHz oscilloscope with the oscilloscope terminating both signals at 50 ohms. The upper trace is a 0 to 5 volt "TTL" step. The P400 was programmed to output 0 (VL) and 10-volt (VH) levels, which are divided by a factor of two by the termination.

  • Page 35: Figure 19. 10 V Pulse With High-Impedance Termination

    P400 output stage. To avoid this situation, do not set the P400 output to swing more than 5.00 volts while driving high-impedance loads. Figure 19. 10 V Pulse with High-Impedance Termination...

  • Page 36: Typical Jitter Performance

    P400s programmed to generate slightly different delays. The delay increase beginning around 10 milliseconds is a result of the phase noise of the TCXO timebase internal to the P400. The OCXO timebase option moves this corner out by at least 10:1.

  • Page 37: Remote Programming

    Remote Programming The P400 can be used as a stand-alone instrument or may be connected to a host computer. The P400 supports serial commands for almost every action that can be performed using the front panel. All commands support both the SCPI long-form and the short-form mnemonic and are not case sensitive;...

  • Page 38: Table 4. P400 Commands

    Table 4. P400 Commands BURst CounterCLear Command: BUR:CCL<CR><LF> Response: OK<CR><LF> Query: BUR:CCL?<CR><LF> Response: count <CR><LF> Description: Resets the burst counter to 0. Sending the query returns the current burst counter value. count will be between 0 and BURst TRIGger – 1.
  • Page 39 BURst:PULse Command: BUR:PUL pulses <CR><LF> Response: OK<CR><LF> Query: BUR:PUL?<CR><LF> pulses <CR><LF> Response: Description: Sets the number of pulses, n, per burst cycle. Pulses can be set from 1 to BURst TRIGger – 1. Example: Set the Burst Pulse value to 32,000 reply: OK<CR><LF>...
  • Page 40 CHANnel Delay/Width Command: CHAN:DW a <CR><LF> Response: OK<CR><LF> Query: CHAN:DW? a <CR><LF> Response: DW<CR><LF> Description: Sets the channel’s timing mode to Delay/Width. The possible values for a are shown below. Channel A Timing Mode Channel B Timing Mode Channel C Timing Mode Channel D Timing Mode Example: Set Channel to D/W, Delay/Width mode.
  • Page 41 CHANnel OFF Command: CHAN:OFF a <CR><LF> Response: OK<CR><LF> Query: CHAN:OFF? a <CR><LF> Response: OFF<CR><LF> Description: Disables the channel’s output. The possible values for a are shown below. Channel A Output Channel B Output Channel C Output Channel D Output CHANnel ON Command: CHAN:ON a <CR><LF>...
  • Page 42 CHANnel POSitive Command: CHAN:POS a <CR><LF> Response: OK<CR><LF> Query: CHAN:POS? a <CR><LF> Response: POSitive<CR><LF> Description: Sets the channel’s output polarity to positive. The channel’s output starts at VL and transitions to VH after the delay time. At the end of the width time the channel’s output transitions from VH to VL.
  • Page 43 CHANnel VHIgh Command: CHAN:VHI a , volts <CR><LF> Response: OK<CR><LF> Query: CHAN:VHI? a <CR><LF> volts <CR><LF> Response: Description: Sets channel a ’s VH to volts . The possible values for a are shown below. Channel A VH Channel B VH Channel C VH Channel D VH volts can be from –4.30 to +11.80 in 0.10 increments.
  • Page 44 CHANnel VLOw Command: CHAN:VLO a , volts <CR><LF> Response: OK<CR><LF> Query: CHAN:VLO? a <CR><LF> volts <CR><LF> Response: Description: Sets channel a ’s VL to volts . The possible values for a are shown below. Channel A VL Channel B VL Channel C VL Channel D VL volts can be from –5.00 to +4.10 in 0.10 increments.
  • Page 45 GATE MODe Command: GATE:MOD mode <CR><LF> Response: OK<CR><LF> Query: GATE:MOD?<CR><LF> mode <CR><LF> Response: Description: Sets the gate mode. The possible values for gate are shown below. Output, TTL high when trigger is enabled. Output, TTL low when trigger is enabled. Input, Trigger is enabled when the input is at TTL high.
  • Page 46 MEMory RECall Command: MEM:REC n <CR><LF> Response: OK<CR><LF> MEM:STO? n <CR><LF> Query: Response: status <CR><LF> Description: Recalls the unit’s configuration in location n . n can be set from 0 to 30. Allow three seconds for the unit to recall the configuration before sending another command.
  • Page 47 MEMory STOre Command: MEM:STO n <CR><LF> Response: OK<CR><LF> MEM:STO? n <CR><LF> Query: Response: status <CR><LF> Description: Stores the unit’s configuration in location n . n can be set from 0 to 30. Allow three seconds for the unit to store the configuration before sending another command.
  • Page 48 STOp Command: STO<CR><LF> Response: OK<CR><LF> Query: None Response: None Description: Sending this command is the same as pressing the STOP button. Example: STO<CR><LF> reply: OK<CR><LF>...
  • Page 49 TIME DELay Command: TIME:DEL n delay units <CR><LF> Response: OK<CR><LF> TIME:DEL n ?<CR><LF> Query: Response: delay <CR><LF> Description: Sets the time delay for channels A through D. The possible values for n are shown below. Delay for channel A leading edge Delay for channel A trailing edge Delay for channel B leading edge Delay for channel B trailing edge...
  • Page 50 TIME RELative To Command: TIME:RELT n m <CR><LF> Response: OK<CR><LF> Query: TIME:RELT n ?<CR><LF> m <CR><LF> Response: Description: Sets the channel n edge relative to channel m edge. The possible values for n and m are shown below. Channel T0 leading edge ( m only) Channel A leading edge Channel A trailing edge Channel B leading edge...
  • Page 51 TRIGger FREQuency Command: TRIG:FREQ freq units <CR><LF> Response: OK<CR><LF> Query: TRIG:FREQ?<CR><LF> freq <CR><LF> Response: Description: Sets the internal trigger frequency from 10 mHz to 10.000 000 00 MHz in 10 mHz increments. The default units are Hertz. The possible values for units are shown below.
  • Page 52 TRIGger INPUT TERMination Command: TRIG:INPUT:TERM imp <CR><LF> Response: OK<CR><LF> Query: TRIG:INPUT:TERM?<CR><LF> Response: imp <CR><LF> Description: Sets the trigger input termination impedance. The possible values for imp are shown below. 50OHM internal termination HIGHZ High impedance internal termination Example: Set the internal trigger termination to 50 Ohm. TRIG:INPUT:TERM 50OHM<CR><LF>...

  • Page 53: Remote Error Codes

    Example: *WAI<CR><LF> reply: OK<CR><LF> 7.2 Remote Error Codes Error codes are returned when a command or query sent to the P400 is incorrect, incomplete, or otherwise not accepted. The formatting for error codes is shown below. ? nn <CR><LF> The possible values for nn are shown in Table 7-1.

  • Page 54: Table 5. Remote Error Codes

    Table 5. Remote Error Codes Error Error Name Comments Number BUFFER OVERFLOW A command overloaded the buffer or no line terminator was found. ABORT RECEIVED An abort character (Ctrl-D) was found while processing input. COMMAND MISSING Indicates no command word was found where one was expected.

  • Page 55: Command Strings

    If the command level changes for a command in the string, then the command must be preceded by a colon. The P400 replies to command strings with a string of responses, followed by a single <CR><LF> command terminator.

  • Page 56: Rs-232 Interface

    Select RS-232 mode on the Auxiliary menu by scrolling down to Remote mode: and turning the spinner knob until RS-232 is shown. A standard serial cable (non-null modem) can be used to connect the P400 to a host computer. Only TX, RX and GND are required for proper operation. For computers that require hardware handshaking the P400 is configured for loopback mode.

  • Page 57: Ethernet Interface

    No Handshake. 7.5 Ethernet Interface The P400 can be equipped with the optional P430 Ethernet Adaptor for remote operation over a TCP/IP network. Select Ethernet mode on the Auxiliary menu by scrolling down to Remote mode: and turning the spinner knob until Ethernet is shown.

  • Page 58: Static-Mode Configuration

    Press the ENTER key. 7.5.3 Connecting the P400 to the Network When the network configuration is complete, you can connect the P400 to the network using the telnet protocol. To connect the P400 to a Windows computer through telnet, follow these steps: Select “Run…”...
  • Page 59 In DHCP mode, type telnet followed by the hostname 2000 as indicated on the Auxiliary menu. A telnet session will open and you can begin sending commands to the P400. The P400 commands are explained in earlier in this chapter.

  • Page 60: Versions, Options, And Accessories

    Optional accessories include an external trigger source AC line adaptor, dual or single 19-inch rack-mount shelves, and a replacement AC-line power supply. The latest P400 application notes, current updates, and new option information may be found at Highland Technology’s website, www.highlandtechnology.com .

  • Page 61: Index

    Index Block Diagram, 8 Inputs, 4 Burst mode, 20 buttons, 15 line, 1, 16, 20, 49 Channel maximum voltage, 2 A-D, 21 remote, 1, 16, 33 dependencies, 20, 22 Interface menu, 21 Ethernet, 53 T0, 20 front panel, 14 timing, 7 rear panel, 16 Clock RS-232, 52...
  • Page 62 Pulse-Train Example, 11 TRIGger INPUT POLarity, 47 TRIGger INPUT TERMination, 48 Rear Panel, 16 TRIGger INPUT VOLTage, 48 Remote control, 33 TRIGger Source, 49 command strings, 51 WAIt, 49 examples, 52 Error Codes, 49 commands, 33 Ethernet, 6, 16, 24, 53 BURst Counter CLear, 34 interfaces, 5 BURst MODe, 34...

Table of Contents