1. Use ATmega8, ATmega168 or ATmega328 microcontroller.
2. 2×16 character LCD display results.
3. One key operation, automatically turn off the power.
4. The shutdown current is only 20nA, which supports battery operation.
5. The low-cost version does not require a crystal oscillator and supports automatic power off. The ATmega168 or ATmega328 of the 1.05k version of the software uses sleep mode to reduce power consumption when there is no measurement.
6. Automatic detection of PNP and NPN bipolar transistors, N, P-channel MOSFETs, JFETs, diodes, dual diodes, thyristors thyristors.
7. Automatically detect the pin layout.
8. Measure the current amplification factor of the bipolar transistor and the threshold voltage of the emitter junction.
9. Darlington transistors can be identified by high threshold voltage and high current amplification factor.
10. For bipolar transistors, MOSFET protection diode detection.
11. Measure the threshold voltage and gate capacitance of the MOSFET.
12. Support the measurement and symbol display of two resistances, the highest four digits and unit display. The two ends of the displayed resistance symbol are the connected tester probe numbers (1-3). So the potentiometer can also be measured. If the potentiometer is adjusted to one end of it, the tester cannot distinguish between the middle and both ends of the pin.
13. The resolution of resistance measurement is 0.1 ohm, and the highest measured value is 50M ohm.
14. A capacitor can be detected and measured. The highest four digits and units are displayed. The value can be from 25pf (8MHz clock, 50pF @ 1MHz clock) to 100mF. The resolution is up to 1 pF (@ 8MHz clock).
15. It can be measured for the equivalent series resistance (ESR) capacitance of capacitors above 2UF. The resolution is 0.01 ohms and displays a two-digit value. This feature requires at least 16K flash ATMEGA (ATmega168 or ATmega328).
16. The symbols of the correct direction can be displayed for both diodes. In addition, the forward pressure drop is displayed.
17. The LED is detected as a diode, and the forward voltage drop is much higher than normal. The dual light emitting diode is detected as a dual diode.
18. The Zener diode can be detected if the reverse breakdown voltage is lower than 4.5V. This will appear as two diodes, which can only be determined by voltage. The sign of the probe around the diode is the same, in this case, you can identify the true anode of the diode by the threshold voltage near 700mV!
19. **** This article understands every year, don’t turn it up ****
If more than 3 diode parts are tested, the establishment of the number of diodes displays another message of failure. This will only happen if the diode is connected to all three probes and at least one is a type diode. In this case, you should only connect two probes and start the measurement again, one by one.
20. Measure the reverse capacitance of a single diode. Bipolar transistors can also be measured if you connect the base to the collector or emitter.
twenty one. Only one measurement is needed to find the connection of the full bridge.
twenty two. Capacitors with values below 25pf are usually undetectable, but can be connected in parallel with a diode or at least 25pf capacitors. In this case, you must subtract the parallel capacitance value.
twenty three. Resistance below 2100 ohms will measure inductance if your ATMEGA has at least 16K flash memory. The range will be from 0: 01mH to over 20H, but the accuracy is not good. The measurement results show only a single component connection.
twenty four. The test time is about two seconds, only the capacitance and inductance measurement will take a long time.
25. The software can set the number of measurements before the power is automatically turned off.
26. Built-in self-test function and optional 50Hz signal to check clock frequency accuracy and wait for call (ATmega168 and ATmega328).
27. Optional equipment for measuring the internal resistance and zero offset self-test capability of the output of the calibration port (ATmega168 and ATmega328). A 100nF to 20uF capacitor is required between pin 1 and pin 3 to compensate the offset voltage of the analog comparator. This can reduce the measurement error of capacitors above 40uF. Using the same capacitor internal correction voltage reference voltage was found to adjust the internal reference to measure the gain of the ADC.
If the test current exceeds the sustain current, the thyristor and the triac can be detected. However, some semiconductor thyristors and triacs have a higher trigger current than the tester can provide. The test current available is only about 6mA! Note that all functions are only used for microcontrollers with more program memory such as ATmega168.