In many low voltage applications, undesired voltage overshoots may occur at the input during the circuit operation. To avoid the harm of this overvoltage, generally use parallel clamps such as fuses or other current limiting devices.
The disadvantage of the parallel protection may be resetting or renewing the protector component. This circuit provides a series protection that turns off the power switch using a serially connected high voltage MOSFET ( IXFH26N50 – Q1) power switch and a fast overvoltage detector IC, MAX1614. The series connected rectifier diode D1 and the power switch is together capable of protecting the load up to +/- 500V of either polarity
The DS2151DK and DS2153DK are ordered and shipped for either T1 or E1 operation. However, the kits are easily converted to operate on the other mode. This application note describes how to convert the demo kits to either T1 or E1 operation.
The DS2151DK and DS2153DK are both shipped with Rt = 0Ω, R5 & R6 are shorted in the PCB. Some of the configurations in the data sheets specify non zero resistors for Rt. In order to place resistors, Rt ≠ 0, the traces must be cut. Carefully cut the traces connecting the through holes for R5 & R6 with an X-acto knife, and solder the resistors in place.
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