Active Discharge Circuit for 400 V or 800 V Systems

Product Highlights > Active Discharge Circuit for 400 V or 800 V Systems

            Active Discharge Circuit for 400 V or 800 V Systems
                    The Vishay active discharge circuit features a discharge of 450 V or 850 V to 60 V in less than 2 seconds
    

Image of Vishay Dale Active Discharge Circuit for 400 V or 800 V Systems The Vishay active discharge reference design for 400 V or 800 V systems highlights the different resistor technologies within the Vishay portfolio. In addition to highlighting wire-wound, thick-film, and MELF resistors, these designs utilize the Vishay MOSFETs and photovoltaic gate driver.

Active Discharge is a known method of discharging the stored energy in a capacitor (or any other energy-storing element) in a controlled manner in which the system voltage can reach a safe value within a certain amount of time. In automotives, this time duration is defined by the car manufacturer according to legal requirements. For example, in automotive applications, the safe voltage is defined as 60 V, and the DC bus voltage must reach this value in less than 5 s after the crash. This is defined by United Nations regulation No. 94 of the Economic Commission for Europe of the United Nations. However, some OEMs prefer more restrictive discharge timing. Therefore, in this application the discharge time is set at less than 2 s.

Features

Discharge 450 V or 850 V to 60 V in less than 2 seconds
High pulse load surface-mounted wire-wound resistors, carbon film MELF resistors, and thick-film technology resistors
Low part count isolated gate drive circuit without the need for an external power supply
Four designs for 400 V systems
Four designs for 800 V systems

Applications

Electric vehicles
Industrial equipment

Renewable energy systems
Power supplies