Posted by Circuits Arena on Monday, 10 November 2014
ZENER DIODE TESTER CIRCUIT DIAGRAM | Diode Polarity Tester Circuit is the artlcle explaining ZENER DIODE TESTER SYMBOL Zener Diode Symbol Zener diodes and are intended specifically for operation in th...
ZENER DIODE TESTER
SYMBOL
Zener Diode Symbol
Zener diodes and are intended specifically for operation in the
reverse breakdown mode primarily as inexpensive voltage references. Diodes whose reverse-breakdown characteristics are controlled precisely during manufacture are called as Zener diodes. This battery operated compact circuit can be made in a small plastic case with two crocodile clip leads as test probes.
ZENER DIODE TESTER CIRCUIT DIAGRAM
The built-in Digital DC Voltmeter (DVM) module obviates the requirement
of an extra voltmeter/multimeter. The DVM reads the voltage drop across
the device under test. This circuit is suitable for testing of ZD up to
30V range.
Zener Diode Test:
- Identify the test leads and connect the ZD to its proper terminals.
- Push S2 and read the DVM. If the readout is > 30V probably the ZD under test is open/have a higher value, and if it is < 1V the ZD is short. Otherwise you can observe a good value.
- This circuit can also be used to check forward voltage drop across
diodes and LEDs at a pre-setted value of current. Here the maximum test
current is near 12 mA with the 2.7K ballast resistor (R3).
- Test current through the device under test can be set to a different
value by changing the value of the ballast resistor (R3). Recommended
value of test current range is 5 to 15mA.
Components for Diode Polarity Tester:
- U1: NE555N IC
- Q1: P55NF0 Power Mosfet
- D1, D3: 1N5819 Schottky Diode ( 1A/40V)
- D2: 1N4752 Zener Diode ( 33V/1W)
- L1: 10µH Inductor (200mA)
- LED1: 5mm Red
- R1, R4: 1K ¼ w
- R2: 10K ¼ w
- R3: 2K7 ¼ w (see text)
- C1: 1nF
- C2: 10nF
- C3: 100µF/63V
- C4: 470µF/25V
- DVM: 3-Wire Digital Voltmeter Module (DVM) / available at eBay!
- S1: SPST Toggle Switch (N/O)
- S2: SPST Push Switch (N/O)
- BATT: 6V (1.5V x 4)
