Agilent 81133A/81134A Pulse Generator User’s Guide sA
Important Notice Warranty © Agilent Technologies, Inc. 2008 Manual Part Number 5988-7401EN Revision September 2008 Printed in Germany Agilent Technologies Herrenberger Straße 130 D-71034 Böblingen Germany The material contained in this document is provided "as is," and is subject to being changed, without notice, in future editions.
Contents Contents Safety Requirements 7 Safety Summary Environmental Conditions Before Applying Power Ground the Instrument Do not Operate in an Explosive Atmosphere Do not Remove the Instrument Cover Initial Inspection Power Requirements Performance Requirements Ventilation Requirements Cleaning Recommendation Declaration of Conformity Introduction to the Agilent 81133A/81134A Pulse Generator Benefits and Key Features Front Panel Overview Input and Outputs Rear Panel Overview Operating the Agilent 8
Contents Using the Graphical User Interface Using the Remote Programming Interfaces Setting Up a Data Pattern Using the Graphical User Interface Using the Remote Programming Interfaces Setting Up a Burst Signal Using the Graphical User Interface Using the Remote Programming Interfaces Setting Up a Repetitive Burst Signal Using the Graphical User Interface Using the Remote Programming Interfaces Setting Up Signals for a Stressed Eye Diagram Measurement Connecting the Instruments Setting Up the 81134A by
Contents Saving and Recalling Settings 83 Updating the Firmware 85 Troubleshooting 87 Index 89 Agilent 81133A/81134A Pulse Generator User’s Guide, September 2008 5
Contents 6 Agilent 81133A/81134A Pulse Generator User’s Guide, September 2008
Safety Requirements The following general safety precautions must be observed during all phases of operation of this instrument. Failure to comply with these precautions or with specific warnings elsewhere in this manual violates safety standards of design, manufacture, and intended use of the instrument. Agilent Technologies Inc. assumes no liability for the customer's failure to comply with these requirements. Before operation, review the instrument and manual for safety markings and instructions.
Safety Requirements Safety Summary Before Applying Power Verify that all safety precautions are taken. The power cable inlet of the instrument is used to disconnect the instrument from the mains in case of hazard. The instrument must be positioned so that the operator can easily access the power cable inlet. When the instrument is mounted in a rack, the rack must be provided with an easily accessible mains switch.
Initial Inspection Safety Requirements Initial Inspection Inspect the shipping container for damage. If the container or cushioning material is damaged, keep it until the contents of the shipment have been checked for completeness and the instrument has been verified both mechanically and electrically. WARNING To avoid hazardous electric shock, do not perform electrical tests when there are signs of shipping damage to any part of the instrument's outer covers or panels.
Safety Requirements Power Requirements Power Requirements NOTE When the front panel switch is off, the instrument is in “standby” mode. The instrument is disconnected from the AC line power only by disconnecting the power cord. The instrument can operate from any single- phase AC power source supplying 100 – 240 V in the frequency range from 47 – 63 Hz. The maximum power consumption is 200 VA with all options installed.
Cleaning Recommendation Safety Requirements Cleaning Recommendation Use a dry cloth or one slightly dampened with water to clean external case parts. Do not attempt to clean internally. WARNING To prevent electrical shock, disconnect the instrument from mains before cleaning.
Safety Requirements Declaration of Conformity Declaration of Conformity DECLARATION OF CONFORMITY According to ISO/IEC Guide 22 and CEN/CENELEC EN 45014 Manufacturer’s Name: Manufacturer’s Address: Agilent Technologies Deutschland GmbH Boeblingen Verifications Solutions (BVS) Herrenberger Str. 130 D-71034 Boeblingen Declares, that the product Product Name: Model Numbers: Product Options: 3.
Introduction to the Agilent 81133A/81134A Pulse Generator The Agilent 81133A and 81134A Pulse/Pattern Generators are high- end, easy- to- use tools for generating pulses, patterns and data at speeds up to 3.35 GHz. They are ideal instruments for testing logic devices (for example, ECL, LVDS, LVPECL) and other digital devices with clock rates from 15 MHz to 3.35 GHz. You can use the Pulse Generators for applications where timing and performance are critical and full control over signal jitter is required.
Introduction to the Agilent 81133A/81134A Pulse Generator Benefits and Key Features Benefits and Key Features Your advantages are: • Fast rise times, low jitter and full parameter flexibility When timing is critical, the 81133A/81134A’s fast rise times, the low jitter and full parameter flexibility make it an ideal pulse, clock and data source. • PRBS from 25- 1 … 231- 1 You can evaluate the performance of a device in eye diagram measurements with PRBS from 25- 1 … 231- 1.
Front Panel Overview Introduction to the Agilent 81133A/81134A Pulse Generator Frequency Divider The freqency of the output signals must always be > 15 MHz. This limits the available range for the frequency divider (for example, for a 32 MHz signal, for the frequency divider, 2 (= 16 MHz) is available, but not 4 (= 8 MHz)). Front Panel Overview The following figure shows the main elements of the front panel.
Introduction to the Agilent 81133A/81134A Pulse Generator Front Panel Overview • Navigation knob Used to navigate through and to change parameter values in an easy way, and also for navigating through the online help. For more information, see “Operating the Agilent 81133A/81134A Pulse Generator” on page 19. • Inputs and Outputs The instrument provides global and channel- specific inputs and outputs as described in the following section.
Front Panel Overview Introduction to the Agilent 81133A/81134A Pulse Generator • Clock Input The clock input is used to apply an external clock signal or a reference signal for the internal PLL if a higher frequency accuracy than 50ppm is required. This input can be AC or DC terminated. If it is DC is terminated, the termination voltage can be set. For more information, see “Clock Sources” on page 73. • Start Input The start input is used to start the instrument on an external signal.
Introduction to the Agilent 81133A/81134A Pulse Generator Rear Panel Overview Rear Panel Overview At the rear panel, you can find the connectors for the remote programming interfaces GPIB, USB and LAN, and the power connector.
Operating the Agilent 81133A/81134A Pulse Generator The instrument provides several navigation buttons that make it easy to scroll through the different pages of the graphical user interface and to change parameter values. Scrolling through the Pages To scroll through the different pages, use the instrument's tab keys (located below the navigation knob). See “Navigation through the Pages” on page 20. Changing Parameter Values To change parameter values, use the navigation knob.
Operating the Agilent 81133A/81134A Pulse Generator Navigation through the Pages Navigation through the Pages The key tabs at the lower left corner of the display allows you to scroll through the different pages (Main, Channel, Data, Aux, and Config) of the graphical user interface.
How to Navigate through the Parameters at one Page Operating the Agilent 81133A/81134A Pulse Generator How to Navigate through the Parameters at one Page The navigation knob makes it easy to move through and set the parameters: © Rotate the navigation knob to move from one parameter to the next. How to Select a Parameter from a Selection List To select a parameter from a selection list: 1 Move the selection to the corresponding list by rotating the navigation knob.
Operating the Agilent 81133A/81134A Pulse Generator How to Select a Parameter from a Selection List 2 Press the navigation knob to open the selection list. Press 3 Rotate the navigation knob to scroll through the list. 4 Select an item by pressing the navigation knob (like clicking with the mouse).
How to Change a Number Field Operating the Agilent 81133A/81134A Pulse Generator How to Change a Number Field You have three possibilities for changing a number field: • By entering new values with the keypad • By using the navigation knob to modify the values for finetuning • By changing single digits Entering New Values To enter a new value: 1 Focus at the number field by rotating the navigation knob to the desired position. 2 Enter the value using the keypad.
Operating the Agilent 81133A/81134A Pulse Generator How to Change a Number Field 3 Modify the unit: – By pressing the respective softkey function (in this case, you can immediately see the changes at the output). Softkey functions to select the unit – OR – By rotating the navigation knob. Press In this case, you have to press Enter or the navigation knob to see the changes at the output.
How to Change a Number Field Operating the Agilent 81133A/81134A Pulse Generator 3 Press and rotate the navigation knob to set the least significant digit to change. Press NOTE This method is useful for fine- tuning. It also changes the values in real- time, so that you can immediately see the changes at the output. 4 Rotate the navigation knob to change the value. 5 Press the navigation knob once when you are done.
Operating the Agilent 81133A/81134A Pulse Generator 26 How to Change a Number Field Agilent 81133A/81134A Pulse Generator User’s Guide, September 2008
Setting Up Generic and Advanced Signals The intention of this chapter is to give the necessary steps to set up generic and advanced signals for first- time users of the Agilent 81133A/81134A Pulse Generator.
Setting Up Generic and Advanced Signals Setting Up a Clock Signal Setting Up a Clock Signal Task Set up two clock signals with 100 MHz and 200 MHz frequencies, a duty cycle of 50%, a high level of 1.0 V and a low level of 0 V. Duty Cycle = 50% 1.0 V 0.0 V f = 200 MHz Duty Cycle = 50% 1.0 V 0.
Setting Up a Clock Signal Setting Up Generic and Advanced Signals Using the Graphical User Interface First Steps Before you start: 1 Put the instrument into operation. 2 Protect the DUT by disconnecting the channel outputs first. Do this by pressing the softkey next to the following function: The open contactor shows you that your DUT is now disconnected. Instrument Settings To set the instrument parameters: 1 In the instrument panel, choose the Pulse/Pattern mode.
Setting Up Generic and Advanced Signals Setting Up a Clock Signal 4 Enable the Channel 1 normal Output: By pressing the respective softkey in the user interface: – OR – By pressing the normal Out softkey for channel 1 next to the Output port.
Setting Up a Clock Signal Channel 2 Settings Setting Up Generic and Advanced Signals To set the channel parameters for channel 2: 1 Switch to channel 2 by pressing the Ch2 softkey . 2 Select the pattern mode Square. 3 Set the Freq. Divider to 2. 4 In the Levels panel: – Switch Ampl to High and set High to 1.0 V. – Set Low to 0 V. 5 Enable the Channel 2 normal Output either: By pressing the respective softkey in the user interface.
Setting Up Generic and Advanced Signals Setting Up a Clock Signal The Channel 2 page now looks as follows: Frequency Divider Reconnect the DUT 32 Reconnect the DUT by clicking the following softkey function: Agilent 81133A/81134A Pulse Generator User’s Guide, September 2008
Setting Up a Clock Signal Generated Signal Setting Up Generic and Advanced Signals If you attach a scope (as DUT), you can immediately see the signal. Use the Pulse Generator’s TRIGGER OUT to trigger the scope. To enable the trigger output: 1 At the Aux page, press the TrigOut softkey function. Indicator TrigOut softkey function The green LED indicates that Trigger Out is enabled. – OR – Press the Trigger Out softkey next to the Trigger Out port.
Setting Up Generic and Advanced Signals Setting Up a Clock Signal The signals as displayed on a standard oscilloscope are depicted below.
Setting Up a Clock Signal Setting Up Generic and Advanced Signals Using the Remote Programming Interfaces The following code performs the same task. Protect the DUT Set up the Instrument //disconnect channels :OUTP:CENT OFF //set mode to Pulse/Pattern :FUNC PATT //set freq to 200 MHz :FREQ 200 MHz Set up Channel 1 //set pattern mode to Square :FUNC:MODE1 SQU //set high-Level to 1 V :VOLT1:HIGH 1.
Setting Up Generic and Advanced Signals Setting Up a Pulse Signal Setting Up a Pulse Signal Task Set up a continuous pulse signal with 20 ns period, a pulse width of 5 ns, an amplitude of 2.0 V and an offset of 1.5 V (high level 2.5 V, low level 500 mV). Pulse Width = 5 ns 2.5 V 500 mV Period = 20 ns Using the Graphical User Interface Instrument Settings To set the instrument parameters: 1 Disable the outputs. 2 In the instrument panel, choose the Pulse/Pattern mode. 3 Set the Period to 20 ns.
Setting Up a Pulse Signal Setting Up Generic and Advanced Signals 5 Enable the Channel 1 normal Output: By pressing the respective softkey in the user interface: – OR – By pressing the normal Out softkey for channel 1 next to the Output port. The Channel page now looks as follows: Pattern Mode Width Levels Reconnect the DUT Generated Signal Enable the outputs: Use the pulse generator’s TRIGGER OUT to trigger the scope.
Setting Up Generic and Advanced Signals Setting Up a Pulse Signal To set up the trigger output: 1 On the Aux page, select the trigger mode Pulse. The frequency of the trigger output equals the system frequency. 2 Enable the trigger output. Trigger Mode TrigOut softkey function The signal as displayed on a standard oscilloscope is depicted below.
Setting Up a Pulse Signal Setting Up Generic and Advanced Signals Using the Remote Programming Interfaces The following code performs the same task. Protect the DUT Set up the Instrument //disconnect channels :OUTP:CENT OFF //set mode to Pulse/Pattern :FUNC PATT //set period to 20 ns :PER 20 ns Set up Channel 1 //set pattern mode to Pulse :FUNC:MODE1 PULSE //set width to 5 ns :WIDT1 5 ns //set ampl to 2 V :VOLT1:AMPL 2.000 V //set offset to 1.5 V :VOLT1:OFFSET 1.
Setting Up Generic and Advanced Signals Setting Up a Data Pattern Setting Up a Data Pattern Task Set up two signals: • A PRBS signal to test a digital transmitter. • A 32- bit pattern signal with NRZ data output format at 500 MHz to check a digital circuit with ECL logic. The pattern is: 11110011100110010010100100000000 NOTE This example is demonstrated with the 81134A instrument. With the 81134A instrument, you can set up both signals simultaneously.
Setting Up a Data Pattern Setting Up Generic and Advanced Signals 6 Enable the Channel 1 normal Output: By pressing the respective softkey in the user interface: – OR – By pressing the normal Out softkey for channel 1 next to the Output port. The Channel page now looks as follows: PRBS Polynome Signal Mode Pattern Mode PRBS ECL Levels Channel Settings for the Pattern Signal To set the channel parameters for channel 2: 1 Switch to Channel 2 by pressing the Ch2 softkey . 2 Switch to the Channel page.
Setting Up Generic and Advanced Signals Setting Up a Data Pattern 6 Enable the Channel 2 normal Output either: By pressing the respective softkey in the user interface. – OR – By pressing the normal Out softkey for channel 2 next to the Output port. The Channel page now looks as follows: Pulse Type NRZ Pattern Mode Data ECL Levels Data Settings for the Pattern Signal To set the data pattern: 1 Switch to the Data page. 2 Enter a Data Length of 32 bits. 3 Switch to the Numeric Edit Mode.
Setting Up a Data Pattern Setting Up Generic and Advanced Signals The Data page now looks as follows: Data pattern length Data pattern for channel 2 Numeric Edit Mode Reconnect the DUT Enable the outputs: Generated Signals Use the pulse generator’s TRIGGER OUT to trigger the scope on the data pattern. To set up the trigger output: 1 On the Aux page, in the Trigger Output panel: – Select the trigger mode Data. One trigger pulse occurs at the start of the repetitive data pattern.
Setting Up Generic and Advanced Signals Setting Up a Data Pattern 2 Enable the trigger output. Trigger Mode TrigOut softkey function The signals as displayed on a standard oscilloscope are depicted below.
Setting Up a Data Pattern Setting Up Generic and Advanced Signals Using the Remote Programming Interfaces The following code performs the same task: Protect the DUT Set Up the Instrument //disconnect channels :OUTP:CENT OFF //set mode to Pulse/Pattern :FUNC PATT //set freq to 500 MHz :FREQ 500 MHz Set up Channel 1 //set pattern mode to PRBS :FUNC:MODE1 PRBS //set polynome to 2^12-1 :FUNC:MODE1 PRBS, 12 //set datamode to NRZ :DIG1:SIGN:FORM NRZ //set predefined levels to ECL values :VOLT1:AMPL 800 mV;
Setting Up Generic and Advanced Signals Setting Up a Burst Signal Setting Up a Burst Signal Task Set up a burst signal consisting of a 32- bit data pattern repeated twice at a period of 500 ps with 50 ps delay and 100 ps pulse width. The data pattern is: 10100000000000000000000000000000 The amplitude is 2.0 V and the offset is 0 V. Start the output at the rising edge of an external signal with 1 V threshold applied at the start input.
Setting Up a Burst Signal Setting Up Generic and Advanced Signals The instrument panel now looks as follows: Instrument Mode Channel Settings for the PRBS Signal Burst Repetition To set the channel parameters: 1 Switch to the Channel page. 2 Set the signal mode to RZ. 3 In the Timing panel: – Switch from Dcycle to Width and set the Width to 100 ps. – Set the Delay to 50 ps. 4 In the Levels panel, set: – The level format to Custom. – Amplitude to 2.0 V. – Offset to 0.0 V.
Setting Up Generic and Advanced Signals Setting Up a Burst Signal The Channel page now looks as follows: Timing Parameter Levels Data Settings for the Pattern Signal To set the data pattern: 1 Switch to the Data page. 2 Enter a Data Length of 32 bits. 3 Enter the data pattern via the keypad for channel 1.
Setting Up a Burst Signal Setting Up Generic and Advanced Signals Reconnect the DUT Auxiliary Settings for Start Input and Trigger Output Enable the outputs: To set the start input and trigger output parameters: 1 Switch to the Aux page. 2 In the Start Input panel, set: – The start mode to Ext. Input. This automatically puts the instrument in “armed” mode. This is indicated by the activated Armed softkey function.
Setting Up Generic and Advanced Signals Setting Up a Burst Signal The Aux page now looks as follows: Armed is activated Parameters to start the output by an external signal Trigger Mode TrigOut softkey function Generated Signal Use the generator’s TRIGGER OUT to trigger a scope. The signal as displayed on a standard oscilloscope is depicted below.
Setting Up a Burst Signal Setting Up Generic and Advanced Signals Using the Remote Programming Interfaces The following code performs the same tasks: Protect the DUT Set Up the Instrument //disconnect channels :OUTP:CENT OFF //set mode to Burst, 2 :FUNC BURST, 2 //set period to 500 ps :PER 500 ps Set up Channel 1 //set signalmode to RZ :DIG1:SIGN:FORM RZ //set width to 100 ps :WIDT1 100 ps //set delay to 50 ps :DEL1 50 ps //set predefined levels to Custom values (Ampl=2V; Offset=0mV) :VOLT1:AMPL 2 V;
Setting Up Generic and Advanced Signals Setting Up a Repetitive Burst Signal Setting Up a Repetitive Burst Signal Task Set up a signal with 4 repeated bursts. Each burst consists of a 32- bit pattern signal with NRZ data output format at 100 MHz to check a digital circuit with LVPECL logic.
Setting Up a Repetitive Burst Signal Setting Up Generic and Advanced Signals The instrument panel now looks as follows: Burst Repetition Instrument Mode Channel Settings for the PRBS Signal Specifies the number of zeros To set the channel parameters: 1 Switch to the Channel page. 2 In the Timing panel: – Set the signal mode to NRZ. – Set the Delay to 50 ps. 3 In the Levels panel, set: – The level format to Custom. – Amplitude to 2.0 V. – Offset to 0.0 V.
Setting Up Generic and Advanced Signals Setting Up a Repetitive Burst Signal The Channel page now looks as follows: Levels Data Settings for the Pattern Signal To set the data pattern: 1 Switch to the Data page. 2 Enter a Data Length of 32 bits. 3 Enter the data pattern via the keypad for channel 1.
Setting Up a Repetitive Burst Signal Reconnect the DUT Generated Signal Setting Up Generic and Advanced Signals Enable the outputs: Use the pulse generator’s TRIGGER OUT to trigger a scope. To set up the trigger output: 1 On the Aux page, in the Trigger Output panel: – Select the trigger mode Pulse. One trigger pulse occurs at the start of the repetitive data pattern. – Set the Ampl to 1 V. – Set the Offset to 0 V. – Set the Divider to 256. 2 Enable the trigger output.
Setting Up Generic and Advanced Signals Setting Up a Repetitive Burst Signal The signal as displayed on a standard oscilloscope is depicted below.
Setting Up a Repetitive Burst Signal Setting Up Generic and Advanced Signals Using the Remote Programming Interfaces The following code performs the same tasks: Protect the DUT Set Up the Instrument //disconnect channels :OUTP:CENT OFF //set mode to rBurst, 4, 4 :FUNC RBURST, 4, 4 //set freq to 100 MHz :FREQ 100 MHz Set up Channel 1 //set signalmode to NRZ :DIG1:SIGN:FORM NRZ //set delay to 50 ps :DEL1 50 ps //set predefined levels to Custom values (Ampl=2V; Offset=0mV) :VOLT1:AMPL 2 V; :VOLT1:OFFS 0
Setting Up Generic and Advanced Signals Setting Up Signals for a Stressed Eye Diagram Measurement Setting Up Signals for a Stressed Eye Diagram Measurement Task Set up signals for a stressed eye measurement by: • Intentionally adding jitter to your signals • Changing the crossover of the eye pattern One-Channel Setup For a one- channel setup, you need: • An 81133A or 81134A instrument • An arbitrary waveform generator to generate additional jitter, for example, the 33250A • A scope for displaying the s
Setting Up Signals for a Stressed Eye Diagram Measurement Setting Up Generic and Advanced Signals Connecting the Instruments Connect the Pulse Generator, the Arbitrary Waveform Generator and the DCA as follows: CAUTION Before disconnecting/connecting any cables make sure that the 81134A output channels are turned off! 81134A Pulse Generator TrigOut Channel 2 86100 DCA Channel 1 Channel 1 Delay Control Input Channel 2 Input Output Trigger In 20 dB Attenuator 33250A Arbitrary Waveform Generator
Setting Up Generic and Advanced Signals Setting Up Signals for a Stressed Eye Diagram Measurement Setting Up the 81134A by Using the Graphical User Interface Instrument Settings To set the instrument parameters: 1 Disable the outputs. 2 In the instrument panel, choose the Pulse/Pattern mode. 3 Set the Period to 1 GHz. Channel Settings To set the channel parameters for channel 2: 1 Switch to the Channel page. 2 Switch to Channel 2 by pressing the Ch2 softkey . 3 Select the pattern mode PRBS.
Setting Up Signals for a Stressed Eye Diagram Measurement Setting Up Generic and Advanced Signals The Channel page now looks as follows: Delay Control Input for Channel 2 (Enabled) Variable Crossover Point Delay Ctrl Sensitivity Reconnect the DUT Generated Signal Enable the outputs: Use the pulse generator’s TRIGGER OUT to trigger the scope. To set up the trigger output: 1 On the Aux page, select the trigger mode Pulse. The frequency of the trigger output equals the system frequency.
Setting Up Generic and Advanced Signals Setting Up Signals for a Stressed Eye Diagram Measurement 2 Enable the trigger output.
Setting Up Signals for a Stressed Eye Diagram Measurement Setting Up Generic and Advanced Signals Setting Up the 33250A Waveform Generator Program a 50 MHz sine wave with an amplitude of 2 Vpp: 1 Press the Freq softkey. 2 With the numeric keypad enter 50 as the frequency. 3 Select the desired unit MHz by pressing the corresponding softkey. 4 Press the Ampl softkey. 5 Enter the value 2 with the numeric keypad. 6 Press the Vpp softkey to select the desired unit.
Setting Up Generic and Advanced Signals Setting Up Signals for a Stressed Eye Diagram Measurement Play with the Settings The delay control input adds additional delay to the signal depending on the voltage that is fed to the input. • On the 33250A, you can change the amplitude and frequency of the signal to show the influence of the delay control input. • Change from sine wave to rectangular wave by pressing the corresponding button.
Using the Agilent 81133A/81134A Pulse Generator CAUTION When using the Agilent 81133A/81134A Pulse Generator, make sure you do not set parameters to values outside of the specified ranges. If any parameters are out of range, the generated signals may not be valid. The instrument does not check if values are within range. For valid ranges, see the Online Help (available by pressing the "?" button on the instrument). This chapter: • Describes different pages of the graphical user interface.
Using the Agilent 81133A/81134A Pulse Generator Pages of the User Interface Pages of the User Interface The instrument has a user interface to simplify entering and monitoring of the signal settings. The user interface is divided into different pages and panels. The following figure shows the instrument panel and the Channel page.
Pages of the User Interface Using the Agilent 81133A/81134A Pulse Generator • Data Page At the Data page, you can set up an arbitrary data pattern up to the maximal available memory (8 kBit) per channel. • Aux Page The Aux page provides controls to specify: – The Clock Source – The Start Input – The Trigger Output • Config Page If you want to program the instrument remotely, the Config page is used to set up all necessary parameters to establish the connection between the instrument and your control PC.
Using the Agilent 81133A/81134A Pulse Generator Combining Parameters for Signal Generation Combining Parameters for Signal Generation The following table shows you how the various modes and parameters can be combined.
Combining Parameters for Signal Generation Using the Agilent 81133A/81134A Pulse Generator – Data in either RZ, R1 or NRZ format – Pseudo random bit stream (PRBS) polynomials For details on these signals, see “Pattern Modes” on page 70. • Burst Mode This mode enables you to generate a burst consisting of data repeated n times followed by continuous zero data. n In Burst mode, exactly one burst of data is output after either: – Applying a external signal at the start input.
Using the Agilent 81133A/81134A Pulse Generator Combining Parameters for Signal Generation Pattern Modes You can select the following pattern modes: • Square Generates a square wave (clock) of fixed width (50% duty cycle). • Pulse Generates pulses with selectable width or duty cycle. • Data Generates data in either RZ, R1 or NRZ format. In RZ and R1 mode, the pulse width can be selected as either width or duty cycle. • PRBS Generates a PRBS polynomial of selectable type in either RZ, R1 or NRZ format.
Combining Parameters for Signal Generation Using the Agilent 81133A/81134A Pulse Generator Signal Modes In Data and PRBS pattern modes, the pulse output format can be selected from RZ, R1, and NRZ. The timing of the different format is shown in the following diagram: 1 1 1 0 0 1 RZ R1 NRZ • RZ Return to 0 pulse format. On every 0 bit of the pattern, the signal remains low.
Using the Agilent 81133A/81134A Pulse Generator Combining Parameters for Signal Generation Variable Crossover You can change the crossover point in range 30% … 70% of the NRZ signal separately for each channel. The variable crossover is used to artificially close the eye pattern, which simulates distortion. The crossover adjustment is not calibrated except for the 50% point. Example 72 The figure below shows the normal and complement output with the crossover point set to 50% and 70% respectively.
Combining Parameters for Signal Generation Using the Agilent 81133A/81134A Pulse Generator Clock Sources The selected clock source defines the time base from which all other timing parameters are derived. You can select between: • Internal The clock is derived from the internal YIG oscillator. • External Enables the external clock input (Clock In) to accept an external clock signal that forms the time base.
Using the Agilent 81133A/81134A Pulse Generator Combining Parameters for Signal Generation – Ext. Direct Allows you to vary the frequency of the external clock signal in the range of one octave. In external direct mode, the internal PLL is bypassed. This ensures that the instrument frequency exactly follows the external clock. For both, Int. Direct and Ext. Direct, range switching occurs at the following frequencies: – 1680 MHz – 840 MHz – 420 MHz – 210 MHz – 105 MHz – 52.5 MHz – 26.
Combining Parameters for Signal Generation Using the Agilent 81133A/81134A Pulse Generator Start Mode When the Ext. Input start mode is selected, the instrument sends the generated signal to the outputs according to the signal applied at the Start In connector. You can define the following parameters that the external signal must meet: • Threshold (voltage) • Termination voltage • Edge (rising/falling) If you select the Ext. Input mode, the instrument automatically switches in armed mode.
Using the Agilent 81133A/81134A Pulse Generator NOTE Timing of Generated Signals The trigger divider does not take the frequency divider of the channels into account. For a frequency divider of n, n trigger pulses are generated for each data packet, starting with the first edge of bit 0 of the data packet.
Timing of Generated Signals Using the Agilent 81133A/81134A Pulse Generator Clock The following figure shows the typical timing for the clock signal. Duty Cycle = 50 % Output Channel 1 Output Channel 2 Freq. Divider = 2 Trigger Out Characteristics • Pulse periods are generated continuously where: – Delay and deskew of all channels is zero. – The duty cycle is fixed at 50%. • The instrument mode is Pulse/Pattern. • The pattern mode is Square.
Using the Agilent 81133A/81134A Pulse Generator Timing of Generated Signals Pulses The following figure shows the typical timing for continuous pulses. Duty Cycle Output Channel 1 Delay Output Channel 2 Freq. Divider = 2 Trigger Out Characteristics • Pulse periods can be either generated continuously or can be started manually or by the arming source. • Delay, pulse width (or duty cycle) and deskew can be set for each channel. • The instrument mode is Pulse/Pattern. • The pattern mode is Pulse.
Timing of Generated Signals Using the Agilent 81133A/81134A Pulse Generator Data Pattern The following figure shows the typical timing for a data pattern. Data Pattern of 32 bits Output RZ Output NRZ 1 1 1 0 1 0 1 1 1 1 Output R1 Trigger Out Characteristics • A data pattern can be either generated continuously or can be started manually or by the arming source. The data length is selectable in the range 32 … 8192 bits (in steps of 32). • The instrument mode is Pulse/Pattern.
Using the Agilent 81133A/81134A Pulse Generator Timing of Generated Signals PRBS See “Data Pattern” on page 79 for for the timing diagram. Characteristics • A PRBS signal can be either generated continuously or can be started manually or by the arming source. The PRBS polynome is selectable from 25 – 1 … 231 – 1. • The instrument mode is Pulse/Pattern. • The pattern mode is PRBS. • You can select between RZ, NRZ and R1 signal modes for each output.
Timing of Generated Signals Using the Agilent 81133A/81134A Pulse Generator Started Burst The following figure shows the typical timing for the started burst. The bursts are started by the rising edge of the arming source. Arming Source Triggered by: External Input Manual Start Data Pattern (Burst of 2) Output 1 0 1 0 0 1 0 Continuous Zeros 1 0 0 0 0 0 0 Trigger Out Characteristics • A burst of repeated data is started manually or by the arming source.
Using the Agilent 81133A/81134A Pulse Generator Timing of Generated Signals Repetitive Burst The following figure shows the typical timing for the repetitive burst. Burst = 4 x Data Pattern Output Data Data Data 4 null data packets Data Channel 1 Trigger Out Characteristics • A burst of repeated data can be either generated continuously or can be started manually or by the arming source. • You can select the number of repeated data in the range 4 ... 16384 (in increments of 4).
Jitter Modulation Using the Agilent 81133A/81134A Pulse Generator Jitter Modulation The external source for jitter modulation is applied to the delay control input. Jitter modulation can be turned on and off individually for each channel. Either one of two fixed sensitivities can be selected. The source for the jitter modulation input is assumed to be either a function generator or an arbitrary waveform generator. Both have the capability of setting the output levels.
Using the Agilent 81133A/81134A Pulse Generator 84 Saving and Recalling Settings Agilent 81133A/81134A Pulse Generator User’s Guide, September 2008
Updating the Firmware Firmware updates of the instrument can be done by using one of the supported programming interfaces. Updates and patches are available on the Agilent Web at: http://www.agilent.com/find/pulse_generator They are applied by downloading the update/patch from the web (single executable) and running it. The connection path to the instrument is queried for the time the executable is run. A warning is issued if a new firmware revision would be overwritten by an older one.
Updating the Firmware 86 Agilent 81133A/81134A Pulse Generator User’s Guide, September 2008
Troubleshooting This chapter provides basic troubleshooting tips that you can use if the instrument is not performing as expected. Instrument out of Specs The specification is valid within +/- 10 degree Celsius after running Selfcalibration. If the operating temperature changes, you can run the SelfCal function. SelfCal is started by pressing the SelfCal softkey on the Main page. Outputs Disabled The outputs are automatically turned off to protect the instrument when they are not terminated correctly.
Troubleshooting Instrument does not Respond If the instrument does not respond when you press a button, it is possible that it is being used remotely. To reactivate the instrument, press the Local key (if this is available). As a last resort, you can power the instrument down and back up. Before you do this, though, make sure that no one is carrying out remote tests using the instrument.
Index Index A environmental conditions requirements 7 advanced signals setup 27 error messages 87 J example burst signal 46 clock signal 28 data pattern 40 pulse signal 36 repetitive burst signal 52 signals for stressed eye diagram measurement 58 jitter modulation 83 example 60 Aux page 67 B benefits 14 internal PLL 74 K channel page pages channel 66 external (clock source) 73 external 10 MHz reference (clock source) 73 key features 14 clock jitter 14 data 14 delay modulation range 14 delay ra
Index P pages Aux 67 Data 67 graphical user interface 66 Main 66 scrolling 19 pages overview 20 parameter selecting 21 parameter values changing 19 pattern modes 70 Data 70 PRBS 70 Pulse 70 Square 70 signal mode NRZ 71 R1 71 RZ 71 signal modes 71 signals for stressed eye diagram measurement example 58 single digits changing 25 softkeys 15 Square (pattern mode) 70 Start Input 17 start mode 75 T tab keys 15 pulse signal example 36 timing clock 77 data pattern 79 PRBS 80 pulses 78 repetitive burst 82 trig
Index Agilent 81133A/81134A Pulse Generator User’s Guide, September 2008 91
Copyright Agilent Technologies 2008 Printed in Germany September 2008 5988-7401EN sA
