Transistor Tracer Transistor Characteristic Curve Tester with 4-inch TFT IPS Screen for Triodes Pairing

Transistor Tracer Transistor Characteristic Curve Tester with 4-inch TFT IPS Screen for Triodes Pairing

Specification:
- Working power supply with positive and negative dual power supply 24V 4A input (sufficient 4A)
- The working voltage of the main control in the board is +3.3V, the working voltage of the LCD screen is 3.3V, the working voltage of the LCD backlight board is +5.8V, and the working voltage of other chips is +/-18V.
- The characteristic curve of a transistor is measured for the collector working scan voltage of NPN transistor from 0 to +24V and PNP transistor from 0 to -24V; the characteristic curve of a transistor diode and resistor is measured for the collector working scan voltage from 0 to +24V.
- The maximum base current of the class wave is 500MA, with a range of 11 magnifications. 500MA/gear (5R), 250MA/gear (10R), 125MA/gear (20R), 49MA/gear (51R), 25MA/gear (100R), 12.5MA/gear (200R), 4.9MA/gear (510R), 2.5MA/gear (1K), 1.25MA/gear (2K), 490UA/gear (5.1K), 200UA/gear (10K).
- The maximum current of the collector is 5A, and the range is divided into 11 magnifications. The collector sampling resistor voltage is 5V, the sampling resistors are: 1R, 2R, 4R, 6R, 9.9R, 19.9R, 39.9R, 78.9R, 146.9R, 266.9R, 486.9R; and the full range current: 5 A, 2.5A, 1.25A, 0.833A, 505MA, 251MA, 125MA, 63MA, 34MA, 18.7MA, 10MA.
- The output characteristic curve scanning line consists of 8 levels, with a single scanning time of 200MS and a total scanning time of 2400MS.
- 4-inch TFT IPS high-definition screen with a resolution of 320 x 480.
- Product size: 106 x 130 x 56mm.

Operational Instruction:
- In order to understand the characteristic curve of a transistor, it is necessary to understand the measuring principle during measurement. When measuring the output characteristic curve of a triode, the step wave current given by the base is not the step wave voltage. The step wave current set for this product is specified in the above specifications. Collector scan voltage 0 to ±24V sawtooth wave power supply.

- Reason for collector current grading: When the collector current is relatively small, the scanning line will be very close, which is not conducive to reading data and the reading will be inaccurate. The magnification level is to increase the collector resistance, and the read voltage will be relatively large. Because it is calculated based on small resistance, the current value needs to be divided by the magnification level, and the instrument will automatically calculate it.

- When measuring based on NPN or PNP, please select the switch according to the model. This switch selects positive or negative operating voltage. NPN requires a positive power supply voltage, while PNP requires a negative power supply voltage. When measuring diodes and resistors, the correct power supply should also be set.

- When using, please make a simple test port adapter board for easy measurement.

- Selection key: short press to rotate and select the testing method; long press to select the function; The plus and minus keys can be long or short pressed to select sub-menus; Return key: short press the sub-menu to return, long press to return to the main interface.

- Measure the output characteristic curve, first select the NPN and PNP polarity conversion switches, such as NPN transistor: long press the selection key to enter this testing mode. Default state: Base mode X11, collector mode X11, scan voltage U12. The displayed values of the time base pole and collector gears need to correspond to the position value of the gear shift switch. First, test in the small gear, and then switch to the large gear to prevent damage to the test triode. The base current of the X1 gear is high, with a maximum of 500MA, and the sawtooth voltage of the U22 scanning voltage is above 20V, so low-power triodes are prone to damage.

- When measuring, scan the voltage U12 in the base gear X11 and collector gear X11, and the gear conversion switch should also be switched accordingly. Press and hold the selection button to immediately start a test. If the curve is found to be wide, it indicates that the collector gear should be rotated counterclockwise. If it is adjusted to X9 position, press the return button briefly, press the selection button briefly to switch to the collector gear, and then use the up and down keys to set the collector gear to X9. Press and hold the selection button to start a measurement again. If switching to X8 or other devices, the above steps are required until a better test curve is obtained.

- If you have already tested and want to change the base or collector gear, you need to rotate the switch to the corresponding position, then short press the return button, short press the selection button to switch to the corresponding gear, adjust the up and down buttons to the corresponding value, long press the selection button to start the test, and in any case, long press the return button to immediately return to the main menu and end the measurement.

- Generally, the scanning voltage of low-power transistors should be set to a small value. For example, when testing T31C, the maximum current is 3A and the withstand voltage is 100V. Therefore, the scanning voltage can be adjusted to U22. If the test current is high and the scanning voltage is at U11, the scanning line will be very short.

- On the measurement interface, the value on the y-axis represents the collector current corresponding to each curve, while the other current corresponds to the base current. ICmax1 and ICmax2 are the collector current values at two locations, corresponding to the current amplification factor ß value (HFE) at that current. It can be seen that the ß value is smaller for larger currents.

- Whether to adjust the base range or collector range depends on the triode being tested. Adjusting the base rate range changes the measured parameter. Mobilizing the electrode magnification range does not change the measured parameters, only expands or densifies the display for easy reading.

- When the output characteristic curve changes the base rate range, both the base and collector current parameters will change on the display screen. Changing the collector rate range only changes the collector current parameter.

Usage techniques and skills:
1. When measuring the beta value of a triode, which is relatively small and the curve is very close, the base rate range should be adjusted to the minimum digital position, that is, when the IB current is large, the collector rate range should be adjusted to the maximum digital position, and the curve will unfold.
2. When measuring the β value of the triode, adjust it in the opposite direction as above.
3. In general, small signal triodes such as 9018 operate at low currents, so IB should adjust the position with a higher magnification range and then adjust the collector magnification range to present a better curve waveform.
4. When the base current IB of a slightly high-power transistor is relatively small, we will see that the IB=30UA curve is very close to the 0MA line. This is because the base bias voltage given is too small, and the triode has just passed the dead zone, or even is still in the dead zone. So we should know that when testing this triode, the base current should be set to a relatively large value, that is, the base rate range should be set to a smaller range, and then the electrode rate range should be adjusted to obtain a more balanced curve.
5. The highest curve of IC high current is shorter than the one below because when the scanning voltage is at its maximum, the voltage on the test resistor is very high, so the voltage on the transistor becomes relatively low.
6. Testing diodes, the voltage drop of ordinary diodes is about 0.7V, the red voltage drop of light-emitting diodes is about 1.7 V, the yellow voltage drop is about 1.8V, the green voltage drop is about 2V, and the blue voltage drop is about 3.5V. For example, for a blue light-emitting diode, the voltage drop measured with a multimeter is 2.8V, and the volt ampere curve is 2.8 until above 3.5V. This indicates that when tested with a multimeter, the conduction current provided by the meter is very small, so the voltage drop is very small, and the actual working value will be greater than the value tested with the multimeter.
7. When testing the emitter junction voltage of the transistor in the diode mode, it is 0.7V (silicon). When the collector and base are tested together, the voltage drop of the emitter junction test will be much less than 0.7V, indicating that the transistor is operating in a saturated state and the conduction voltage should be less than 0.7V.
8. Since it is not a dedicated test resistor, the resistance value is tested in the diode mode. The curve with a resistance value greater than 1K is very close to the horizontal axis, and it is only easy to observe the resistance test curve in the tens to hundreds of ohms range. The limit of the volt ampere curve of a resistor: The volt ampere curve of an open circuit resistor overlaps with the horizontal axis, while the volt ampere curve of a short circuit resistor overlaps with the vertical axis. That is to say, the larger the resistance, the closer the curve is to the horizontal axis, and the smaller the resistance, the closer the curve is to the vertical axis.

Package Included:
- 1 x Transistor Characteristic Curve Tester