Current Sense Resistor – Vektrex
Current sense resistor model VCSR simply and accurately converts pulsed or DC current to a voltage that may be measured. The VCSR’s low temperature coefficient allows accurate measurement of waveform tilt; even at high current levels; to 44 A pulsed mode.
Measure Small Current Details With Accuracy
Connect the VCSR inline with a digitizing voltmeter to view and measure fine detail in the current waveform. Small distortions at the top of the waveform and recovery from overshoot are easily detected and measured. The VCSR’s low inductance minimizes the overshoot errors that may occur when using a shunt allowing true device data to be measured.
Amp Second Product Calculations
The accurate VCSR is useful to determine optical measurement corrections for pulsed LED and laser measurements such as amp-second corrections and corrections based upon a pulse profile factor.
Accurately View Current Waveform
Measure current accuracy and accurately view the current waveform generated by your current source/source measure unit. With VCSR, a more accurate current representation is possible at a lower cost than with other instruments. Compare current waveforms using the inline VCSR and Tektronix probe.
Applications
- Non-isolated current sensing
- Pulsed current visualization
- Current accuracy confirmation in all operational modes
- Waveform tuning
- Rise time and overshoot measurement
- Amp-second product calculations
Performance Specifications
| Model | Nominal Resistance Ω | Max DC Current A (Pulse Time >10ms) | Max Pulsed Current A | Recommended Pulse Current A (Pulse Time <10ms) |
|---|---|---|---|---|
| VCSR-0.05 | 0.05 | 7.7 | 44 | I peak < 7.7 / D |
| VCSR-0.1 | 0.1 | 5.4 | 31 | I peak < 5.4 / D |
| VCSR-1 | 1 | 0.7 | 7 | I peak < 0.7 / D |
Note: D is duty cycle = Pulse time/Period
| Type | Current Sensing |
| Connection | Inline |
| Senses | 1AC, DC or Pulsed DC Non-isolated |
| +/- Current Terminal | Safety Banana Jack – on top |
| Voltage Output | BNC Female Connector – on top |
| Size | 2.772″ x 2.026″ x 1.063″ |
| Mounting | Two screw hole locations |
| Output Cable | 50 Ω coax cable |
| Bandwidth (+/- 3dB) | 8 MHz |
| Uncalibrated Accuracy, % | 1 |
| Calibrated Accuracy, % | 0.1 |
| Inductance | Very low |
| Temp Coefficient, ppm | 15 |
| Customization | Yes, contact Vektrex with your requirements |
VCSR Size Dimensions
How To Use Vektrex Current Sense Resistor
The VCSR is easy to place in-line in the load circuit (ideally near the load). Convenient mounting flanges allow it to be permanently secured in a test station. Current connections are via banana jack connectors and the voltage output signal is available on a BNC connector.
Use VCSR with Vektrex SpikeSafe SMU
Vektrex developed Control Panel software application controls the instrumentation and graphically portrays the pulse shape. Control Panel data is also exportable and may be imported into a database or other applications for use.
The device is a 1 A LED. To measure the pulse overshoot, a 1ms pulse was generated using Vektrex SMU Part Number: PSMU-PRF-5-50us. The 0.4% overshoot is measured using Vektrex current sense resistor part number VCSR-0.1.
Using the appropriate VCSR and Vektrex developed Control Panel Software Application it is easy to verify current accuracy in all LED/Laser drive modes including DC, Constant Current, Pulsed Current, CW, QCW.
VCSR Calibration Value
The VCSR calibrated accuracy is 0.1%. With calibration, the shunt resistance value is provided. When using a calibrated current sense resistor and Vektrex Control Panel software application, simply click on the Use Shunt Resistance box in the Control Panel Digitizer Settings tab and enter the VCSR’s calibration value. Digitizer captures and statistics are then scaled in amps instead of volts.
Contact Us
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