C1701C Triac Controller – Zero Voltage Switch UPC1701C

Part Number: C1701C, UPC1701C

Function: Zero Voltage Switch

Manufacturer: NEC

Package: DIP 8 Pin Type

Images:C1701C pdf datasheet


Zero Voltage Switching (ZVS) is a technique used in power electronics to minimize the switching losses and improve the efficiency of high-frequency power converters, such as DC-DC converters or inverters.

In a typical power converter, the switches (usually MOSFETs or IGBTs) are turned on and off to control the flow of current and voltage. During the switching process, there is a brief period when both the voltage and current are non-zero, resulting in power dissipation and switching losses.

ZVS aims to reduce these losses by synchronizing the switching of the power devices with the voltage or current waveform, such that the switch turns on or off when the voltage or current across it is close to zero. By doing so, the switching losses and stress on the power devices are minimized.


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C1701C nec UPC1701C

The Triac controller is designed to regulate the power delivered to the load by adjusting the conduction angle of the Triac. The conduction angle refers to the portion of the AC waveform during which the Triac is allowed to conduct current. By varying the conduction angle, the average power delivered to the load can be controlled.

The operation of a Triac controller involves triggering the Triac at specific points in the AC waveform to turn it on and allowing it to remain on until the next zero-crossing of the AC voltage. This technique is known as phase control or phase angle control.

There are different methods for triggering the Triac, such as:

1. Zero-crossing triggering: The Triac is triggered at the point where the AC voltage crosses zero. This method is commonly used for resistive loads.

2. Burst firing: The Triac is triggered for a predetermined number of cycles during each half-cycle of the AC voltage. This method is often used for inductive loads.

3. Pulse-width modulation (PWM): The Triac is rapidly switched on and off within each half-cycle to achieve precise control of the power delivered to the load.

C1701C Datasheet