Analog Devices LT4363 | Demoboard DC2062A-B

Description

Demonstration circuit 2062A showcases the LT®4363 surge stopper in a 12V, 3A ISO-7637-2 application. Inputs of up to 50VDC and load dumps of up to 100V are limited to 25V at the output. The MOSFET is protected against output overloads by current limiting. Sustained overvoltage or overcurrent conditions cause the LT4363 to turn off after a timer delay. The LT4363-1 (DC2062A-A) latches off and is reset by pulling SHDN low for at least 100μs. The LT4363-2 (DC2062A-B) automatically retries after a cool down delay; retry is inhibited if OV is higher than 1.275V.

Danger! High voltage testing should be performed by qualified personnel only. As a safety precaution at least two people should be present during high voltage testing.

Board LayoutDC2062A is designed to withstand load dump. This high voltage is stood off by RUV4, ROV4, R7, RLED2, Q1, Q4. Maximum input voltage is limited by Q1’s 100V BVDSS rating. The permissible time at 100V is limited by MOSFETsafe operating area (SOA) and R7, which dissipates slightly less than 1.2W and is capable of doing so for at least 500ms.

The minimum spacing is limited by 1206 pad spacing where the gap between solder pads is 2mm, or just under 80mils. Thus, the spacing between the input plane and all other board traces is maintained at a minimum of 2mm.As a point of reference, a 2mm needle gap in air breaksdown well above 1kV.

More information

• Datasheet
• IC product information