Current Regulative Diode CRD

Current Regulative Diode CRD

This diode maintains a constant current flow even when the voltage fluctuation occurs.
It helps supply a constant current over a wide range of voltages from below 1 V to 100 V. This makes it possible to supply a constant current to load despite voltage fluctuations, changes in load resistance, ripple voltage, etc.
Constant current circuits have complex component configurations and require complicated designs. However, with SEMITEC CRDs, it is possible to easily achieve the constant-current characteristics with just a single component.

Rated voltage

Maximum voltage that can be applied by pulsed energizing

Pinch-off current

When the applied voltage is increased, the state where it enters the constant current region that maintains a constant current is called pinch-off, and the current value at that time is the pinch-off current.

Knee point characteristic

The current value that is 80% of the pinch-off current is the knee point current Ik (mA), and the knee point voltage Vk (V) is the voltage applied at that time.

Clamping current ratio I 100V/Ip

Ratio of pinch-off current to current at applied voltage of 100 V

Clamping current ratio I 30V/Ip

Ratio of pinch-off current to current at applied voltage of 30 V

Maximum working voltage

Maximum voltage that can be applied by continuous DC current

Series connection

Applied voltage can be expanded by series connection of CRDs.
As a precaution when connecting in series, connect a zener diode in parallel so that the maximum working voltage of the CRD is not exceeded.

Series connection

Parallel connection

The current value can be expanded by connecting CRDs in parallel.
For example, if 10mA and 15mA diodes are connected in parallel, the current value will be 25mA.
There is no limit to the number of connections. For example, connecting 10 18mA diodes in parallel can create a large current of 180mA.

Parallel connection
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