Download Automated TFT Noise Characterization Platform Test Bench

P01345 – Automated TFT Noise Characterization Platform
Test Bench Descriptions
Equipment
Test Benches Needed
Dynamic Signal Analyzer
TB1, TB2, TB5
SR570
TB5, TB6
Oscilloscope
TB7, TB8, TB9, TB9, TB11
Network Analyzer
TB12
1kΩ Resistor
TB3, TB10
RF Signal Generator
TB12
Lab Computer
TB1, TB2, TB3, TB5, TB6, TB8, TB9, TB10
PN4117 Low Noise JFET
TB2
1MΩ Resistor
TB9
Power Supply
TB11
10Ω Power Resistor
TB11
Table 1: List of Equipment needed for each Test Bench
1. Test Bench 1 (TB1) – LNA Gain and BW
a. Set all bias sources to 0.
b. DUT is an open-circuit.
c. Use DSA Transfer Function Measurement feature to determine the system gain and
bandwidth for each gain setting in the Low Noise Amplification subsystem.
2. Test Bench 2 (TB2) – System Noise Floor and Measurement Frequency Range
a. DUT is PN4117 Low Noise JFET.
b. Set bias sources to various points in operational range.
c. Perform Noise Measurement
d. Compare results to specified JFET noise in datasheet.
3. Test Bench 3 (TB3) – System Noise Floor and Measurement Frequency Range
a. DUT is a 1kΩ resistor (Thermal Noise of (4kTR)1/2 ).
b. Set bias sources to various points in operational range.
c. Perform Noise Measurement
d. Compare results to specified JFET noise in datasheet.
4. Test Bench 4 (TB4) – Input Referred Noise of LNA
a. DUT is an open circuit.
b. Perform Noise Measurement
c. Divide measured noise by gain of amp.
d. Perform measurement for all gain settings.
5. Test Bench 5 (TB5) – Bias Current Source Noise
a. DUT is an open circuit.
b. Connect DUT DRAIN connector to SR570 Amplifier
c. Set Bias Current Source to representative values in operational range.
P01345 – Automated TFT Noise Characterization Platform
Test Bench Descriptions
d. Set SR570 source current to those same values.
e. Measure noise at output of SR570 using Dynamic Signal Analyzer.
6. Test Bench 6 (TB6) – Bias Voltage Source Noise
a. DUT is an open circuit
b. Connect Bias Voltages to SR570 input.
c. Measure Noise at output of SR570 using Dynamic Signal Analyzer.
7. Test Bench 7 (TB7) – Settling Time of Bias Circuitry
a. Solder test points to filter capacitors.
b. Measure 99% settling time of filter caps under worst-case switching conditions (0-10V
change) using oscilloscope.
8. Test Bench 8 (TB8) – Bias Voltage Range
a. Use software to set Bias Voltages to maximum value (10V)
b. Check output voltage with oscilloscope after settling.
9. Test Bench 9 (TB9) – Bias Current Resolution
a. DUT is large resistor (1Mohm)
b. Use software to configure bias current to minimum value
c. Use software to configure bias current to minimum value + 1LSB
d. Use oscilloscope to measure voltage difference across DUT.
10. Test Bench 10 (TB10) – Bias Current Range
a. DUT is a 1kΩ Resistor.
b. Use software to set bias current to maximum value.
c. Use an oscilloscope to measure voltage across DUT.
11. Test Bench 11 (TB11) – Battery Life
a. Use Linear Regulated Bench-top Power Supply for +/- 18V
b. Use Current Sense resistor in line with + and – rails.
c. Measure average voltage on a 10Ω power resistor throughout 10 measurement cycles
with an oscilloscope.
d. Calculate average current, then average power, over the time taken for 10
measurements.
e. Use system under battery power for 1 full day of measurement to determine if battery
life is usable.
12. Test Bench 12 (TB12) – RF Shielding Effectiveness
a. Use RF Signal Generator to generate an output signal
b. Use network analyzer to detect signal when outside of box and when inside.
P01345 – Automated TFT Noise Characterization Platform
Test Bench Descriptions
13. Test Bench 13 (TB13) – Ground Loops
a. It is very difficult to create a quantitative test for ground loops. Their existence will
manifest itself in 60Hz noise that is difficult to eliminate.