What is the difference between latching current and holding current

Once latched, the gate signal can be removed and it will stay conducting latched until the current falls to the level called the holding current. Clearly the "holding" current is less than the latching current. Latching depends on current gain to create 2 Vbe drops then positive feedback of SCR holds them until net saturated hFE which is lower thus no external current input to stay held, rather load current or zero crossing v, to get unlatched.

When current is reduced such that the positive feedback cannot sustain the latch with some reduce load current due to lower voltage drop. In simple terms it is different due to external trigger currents and internal self latching bias current ratios.

Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Asked 3 years, 1 month ago. Active 3 years, 1 month ago. This is allied with the turned-off method. This is allied with turned on a method. This current is always below the latching current. This is around two to three times above the holding current.

The SCR will be deactivated once the anode supply decreases to below 5mA for the particular holding current rating mA within the datasheet. The holding current value, as well as latching current value, is stable. Latching Current and Holding Current Ratio Generally, latching currents are higher than the holding currents used for high rating thyristors.

But they can drop to 0. Usually, the 20A thyristor used in this is BT and the ratio of this is 1. Consequently, if the total number is in use, then it can be taken like 2 at 25 degrees centigrade. Thus, this is all about brief information about latching current and holding current. From the above information, finally, we can conclude that latching current is the highest anode current which is used for maintaining the thyristor turned on instantly once the gate signal is detached.

Similarly, the holding current is the lowest anode current which is used for maintaining the thyristor in conducting state. Notify me when new comments are added.

Perfect Reply. Latching Current. Holding Current. It is related with turn on process of SCR or thyristor. It is related to turn off process. Minimum current above which gate losses its control.