What is saturation current?
Definition of saturation current : the limiting current through an ionized gas or an electron tube such that further increase of voltage produces no further increase in current.
How do you calculate saturation current in a pn junction diode?
Hint: We know that the current that flows in reverse bias PN junction diode is called reverse saturation current. From the diode current equation I=Is(eVηVT−1) the current should decrease as the temperature is increased but the opposite happens.
How do you find saturation current?
Attachments. The reverse saturation current (Is) for a diode is typically modeled as I = Is * (e^(V/(nVt)) – 1). This model is applicable to LEDs only for very low forward currents. For forward currents above a few mA, the ohmic losses in the LED must be included to accurately model the forward voltage.
What is reverse saturation current of a pn junction diode?
In a PN junction diode, the reverse saturation current is due to the diffusive flow of minority electrons from the p-side to the n-side and the minority holes from the n-side to the p-side. Hence, the reverse saturation current depends on the diffusion coefficient of electrons and holes.
Why is it called saturation current?
The maximum value of the photoelectric current is called the saturation current. Saturation current implies that all the photoelectrons emitted by the emitter are immediately collected by the anode.
What causes saturation current?
The reverse saturation current is the part of the reverse current in a semiconductor diode which is caused by the diffusion of minority carriers from the neutral regions to the depletion region.
How do you calculate current in a diode?
Hence if the temperature increases from room temperature (25° C) to 80° C, the voltage drop across the diode will be (80-25) x 2.5 mV = 137.5 mV.
What is saturation current in semiconductor?
The saturation current (or scale current), more accurately the reverse saturation current, is that part of the reverse current in a semiconductor diode caused by diffusion of minority carriers from the neutral regions to the depletion region. This current is almost independent of the reverse voltage. (
What is saturation current in diode equation?
For silicon diodes a typical saturation current is I S = 1 0 − 12 A \text I_{\text S}=10^{-12}\,\text A IS=10−12A. k is Boltzmann’s constant, T is the temperature in kelvin, and q is the charge on an electron in coulombs.
What is saturation diode?
Saturation current. The saturation current or, more accurately, the reverse saturation current is that part of the reverse current in a semiconductor diode caused by diffusion of minority carriers from the neutral regions to the depletion region. This current is almost independent of the reverse voltage.
Why does current saturates in photoelectric effect?
The number of electrons emitted per second is fixed. SO, SATURATION CURRENT IS THAT CURRENT WHEN THE RATE OF FLOW OF CHARGE IN THE CIRCUIT BECOMES EQUAL TO THE RATE OF EMISSION OF ELECTRONS .
Why reverse current is called reverse saturation current?
In a reverse characteristic of pn junction,current increase in range of nano amp(silicon) or microamp(ger)with respect to reverse voltage . when voltage breakdown occurs,current remains constant and not increase eventhough there is increase of voltage. this current is known as reverse saturation current.