When forward biased it behaves like an ordinary silicon diode – a large forward recent passes, and the forward diode voltage is normally 0.7 V. Avalanche diodes can be found with maintaining voltages from many voltages to many thousands volts and with energy dissipation ratings around 50 Watts.
The temperature tenderness of a Zener diode (temperature coefficient) is provided as a portion modify in reference voltage per centigrade degree modify in diode temperature. This quantity is generally in the number of +/- 0.1 percent per deg C. The direction of the modify is related to the process of dysfunction (avalanche multiplication versus Zener breakdown). Usually, if the reference voltage is over 6V the coefficient is good, if below, negative.
Some companies have made temperature compensated reference diodes by combining an optimistic temperature coefficient dysfunction diode with a ahead partial, negative heat coefficient, silicon diode in a single deal (i.e. the generic 1N829, a 6.2V reference diode with a heat coefficient of +/- 0.0005 % per deg D around a range of -55 to +100 deg C). Rather than use a single larger diode it’s frequently better to put multiple breakdown 2cl77 diodes in series when developing a higher voltage reference. This mix enables higher voltage, larger energy dissipation, lower heat coefficient, and decrease dynamic resistance (the reciprocal slope of the volt-amp bend in the functioning region). Needless to say, this is a more expensive alternative than a single diode.
Diodes come in many forms and sizes. High-current diodes are often mounted on a heat-sink system to reduce their running temperature. It is possible to put diodes in parallel to improve the current-carrying volume, but the VI faculties of both diodes must certanly be carefully matched to ensure recent divides evenly (although a small resistor may be put in line with each diode to simply help equalize the currents). All diodes involve some loss recent (current that gets through whenever a diode is reverse-biased).
That leakage current-better called the opposite current (IR)-is very small, typically within the nano ampere range. Diodes also provide a optimum allowable reverse voltage, maximum opposite voltage (PRV), or top inverse voltage (PIV), over which a sizable current may flow in the wrong direction. If the PIV is exceeded, the diode could get zapped and may become completely damaged. The PIV for diodes differs from several volts to around several thousand volts. One technique for achieving an efficiently larger PIV is to put diodes in series. Again, it is very important that diodes are matched to ensure that the opposite voltage breaks similarly (although a small resistor put into similar with each diode may be used to equalize the opposite voltages).
Other things to consider about diodes contain optimum ahead current (IF), capacitance (formed over the pn junction), and reverse recovery time. Most diodes have a 1-prefix situation (e.g., 1N4003). The two stops of a diode usually are famous from each other with a mark. For glass-encapsulated diodes, the cathode is specified with a dark group, whereas black-plastic encapsulated diodes work with a bright band. If no icons exist (as seen with many energy diodes), the cathode might be a bolt like piece. This part is put through a heat-sink device (piece of metal with a hole) and is mounted down by a nut. A fiber or mica machine can be used to separate the cathode electrically from the material heat drain, and a unique plastic oil is positioned between the machine and heat drain to improve thermal conductivity.
A zener diode is just a unit that acts as a typical pn-junction diode as it pertains to ahead biasing, but it also has the capability to perform in the reverse-biased way whenever a unique description voltage (VB) is reached. Zener diodes routinely have dysfunction currents in the range of a few volts to some hundred volts (although bigger successful description voltages may be reached by putting zener diodes in series).