371A Tektronix Curve Tracer Used

The 370-series digital curve tracers offer several advantages over analog curve tracers:

• Higher voltage and current sourcing capability (up to 3000 V and 400 A)
• Higher resolution voltage and current measurements (down to 1 pA and 50 μV)
• View a family of curves without flicker
• Display a reference curve to measure variations due to temperature, etc.
• Voltage, current, DC beta, and slope measurement with built-in cursor measurements
• Store curves and setups for consistent tests and measurements based on reference curves
• Full-color printouts using an HPGL plotter instead of expensive Polaroids
• Automate tests with computer and software (e.g., Metrics, LabView, etc.)

Collector Supply
Modes (positive and negative polarities for both modes)

• High Current: 250 s pulses with maximum peak of 30 V.
• High Voltage: Full rectified sine with maximum peak of 3000 V (positive and negative polarities for both modes)

Output
High-Current (pulsed) Mode:

• Peak Voltage: 30 V +10%, –5%; Peak Current: 400 A; Maximum m Power: 3 kW
• Peak Voltage: 30 V +10%, –5%; Peak Current: 40 A; Maximum m Power: 300 W

High-Voltage Mode:

• Peak Voltage: 3 kV +10, –0%; Peak Current: 40 mA ±20%; Maximum m Power: 30 W
• Peak Voltage: 3 kV +10, –0%; Peak Current: 4 mA ±20%; Maximum m Power: 3 W
• Peak Voltage: 300 V +15%, –0%; Peak Current: 4 mA ±20%; Maximum m Power: 300 mW
• Peak Voltage: 300 V +15%, –0%; Peak Current: 0.4 mA ±20%; Maximum m Power: 30 mW
• Polarities: NPN+: Positive; NPN–: Negative.
• Variable Collector Supply Range: Continuously variable from 0% to 100% in 0.1% resolution.
• Pulsed Collector Supply Pulse Width: 250 μs 10%.
• Pulsed Collector Repetition Rate
• 3 kW: 0.25 times line frequency.
• 300 W: 0.5 times line frequency.
• Loop Compensation (High Voltage mode): Stray capacitance between collector terminal and ground is compensated for up to a maximum of 100pF.
• Circuit Breakers: Both the high-voltage and the high-current supplies have breakers which operate independently. The high-current output breaker opens automatically in an over-current condition. Both breakers can be operated manually.

Vertical Display System Collector Current Measurement
Vertical Range (in 1-2-5 increments)

• 3 kW maximum: 1 A/div to 50 A/div.
• 300 W maximum: 500 μA/div to 5 A/div.
• 30 W maximum: 100 μA/div to 500 μA/div.
• 3 W, 300 mW maximum: 10 A/div to 500A/div.
• 30 mW maximum: 1 μA/div to 50 μA/div.
• Accuracy – Within 0.1 vertical division.
• Cursor Accuracy (nonstore mode, window cursor) – Readout X 2% plus 0.2 div of vertical setting.

Horizontal Display System Collector Voltage Measurement
Vertical Range (in 1-2-5 increments)

• 3 kW, 300 W maximum: 100 mV/div to 5V/div.
• 30 W, 3 W maximum: 50 V/div to 500V/div.
• 300 mW, 30 mW maximum: 5 V/div to 50V/div
• Step Generator Voltage Range (VBE): 100 mV/div to 5 V/div (in increments of 1-2-5).
• Accuracy: Within 0.1 horizontal division.
• Cursor Accuracy (nonstore mode, window cursor): Readout times 2% plus 0.2 div of the horizontal setting.

Step Generator

Current Mode–High-Current (pulsed) Mode:

• Step Range and Waveform: 1 mA/step to 2 mA/step pulse
• Maximum Current: Step/offset amplitude setting X 20, maximum 20 A at 2A/step
• Maximum m Voltage: 10 V ±20%

High-Voltage Mode:

• Step Range and Waveform: 1 μA/step to 2 mA/step stairstep
• Maximum Current: Step/offset amplitude setting X 20, maximum 20 A at 2A/step
• Maximum m Voltage: 10 V ±20%
• Ripple, Noise: Step/offset amplitude setting X 1% plus 10 nA.
• Pulse Width (collector supply high-current mode, 1 mA/step step/offset amplitude setting): 500 s ±10%.

Voltage Mode High-Current (pulsed) and High-Voltage

• Mode:
• Step Range and Waveform: 200 mV/step to 5 V/step stairstep
• Maximum Current: 100 mA +50%,–20%
• Maximum m Voltage: Step/offset amplitude setting X 20, maximum 50 V.
• Ripple, Noise: Step/offset amplitude setting X 1% plus 10 mV,
• Number of Steps: 0 to 10 except 0 to 5 for the 5 V/step and 2A/step ranges.
• Step Polarity: Same as collector supply polarity. Reverse with STEP-INVERT button.

Step Rate

• Pulse: 0.25 X the line frequency at 3kW, 0.5 X the line frequency at 300W.
• Stairstep: 2 X the line frequency.
• Offset: 0 to 10 X the step/offset amplitude setting with 1% resolution except 0 to 5 X at 5V/step and 2A/step settings. Polarity is same as the step signal.
• Test Fixture: Designed to allow easy connection to a variety of devices. Includes an integral safety enclosure to assure operator protection. Special patch cords are provided for connecting large devices.

Metrics Software

• Recommended Computer Configuration: Minimum processor: 386DX/33 MHz IBM compatible computer.
• Free memory: 8 Mb minimum.
• Disk space: At least 14 Mb.
• Floppy drive: 1.44 Mb 3.5-inch.
• Operating system: Microsoft Windows 3.
• Interface cards: National Instruments GPIB card.

The 371A high-power curve tracer performs DC parametric characterization on a wide variety of power semiconductors including thyristors, SCRs, IGBTs, and power MOSFETs. The high-voltage collector mode permits testing the Off-Characteristics of a device up to 3000 volts.
The pulsed high-current collector mode provides output current pulses greater than 400 amps peak for testing On-Characteristics. It also permits high-power testing up to 3,000 watts. In the sweep measurement mode, the 371A automatically constructs a family of curves while stimulating the device with low-duty-cycle pulses. With this capability, power curves can be displayed without excessive heating of the device.

Interactive, Programmable Control
Interactive control of all 370A/371A measurements is accomplished from the full featured front panel or over the GPIB. Every operating parameter can be controlled using a GPIB controller. For interactive control, Metrics software provides complete control and analysis without having to program the instrument. 370/371-series Lab-View drivers are available from the Tektronix BBS. These drivers have many of the building blocks for creating a custom measurement solution.

Store and Recall Setups and Digitized Curves
Up to 64 digitized characteristic curves can be stored on a diskette and recalled at the touch of a button. A live curve can then be compared with a previously stored curve to assess temperature drift or other changes in operating parameters. To help identify the data, up to 24 characters of text may be used to label or annotate the curve data.

Operating parameters can be adjusted, stored, and recalled using several storage methods including the 370A/371A non-volatile memory, the built-in DOS compatible floppy disk, or to an external GPIB controller.

Test Fixturing
A test fixture which provides safe device enclosure to ensure operator protection during measurements is provided as a standard accessory. The test fixture accommodates standard A1001 through A1005 adapters with Kelvin sensing, 3-pin adapters without Kelvin sensing, and the A1023 and A1024 surface-mount adapters.

Direct Hardcopy
Plotter output data can be sent directly from the 370A/371A without the need for an external controller. Plotting can continue while the 370A/371A performs the next tasks.

Test and Measurement Software Option
Metrics ICS Interactive Characterization Software (Tektronix PN 063-1649-00) combined with the 370/371 driver (Tektronix PN 063-1650-00) offers computer-controlled DC parameter characterization and analysis of numerous semiconductor devices. Every aspect of instrument control and data analysis is available through a set of interactive dialog boxes that are configured in a graphics-oriented Microsoft Windows environment.

Metrics ICS can make measurements that are not available on a manually operated instrument, including the ability to sweep any supply. Extensive data management capabilities include project files, data export, DDE links, and search capabilities. Metrics ICS built-in automation capabilities include conditional pass/fail testing and result logging.

Labview™ Driver
370A and 371A drivers for National Instruments Lab-View software is available from the Tektronix Bulletin Board Service. These drivers allow setting most controls in the instrument, saving data to disk, and displaying the data on the computer screen. Since LabView is a graphical programming language, the drivers can be modified to suit a particular measurement requirement. To download either driver, set your modem for N,8,1,19,200 baud and dial 503-627-5658. Once logged in, select the download option and type TEK370.ZIP to download the 370 driver or TEK371.ZIP to download the 371 driver.