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dc1575bfa

DEMO MANUAL DC1575B

OPERATION

The DC1575B is used to evaluate the LTC

®

4362 in two 

protection configurations selected at JP2 for overvoltage 

and overcurrent protection, or overvoltage, overcurrent, 

and negative voltage protection. The device in need of 

protection is connected to the OUT test point or to the 

USB output connector J2. An input supply is connected 

at V

IN

 or a USB source is connected at J1.

ON

 Control

The 

ON

 pin on the LTC4362 is controlled at JP1. Select 

ENABLE to enable the LTC4362, or DISABLE to enter a 

low current sleep mode.

Protection OV/OC

The first selection at JP2 is OV/OC protection which pro-

tects against overvoltage and overcurrent. The LTC4362 

turns on an internal N-channel MOSFET when the input 

voltage is below the overvoltage threshold. An internal 

current sense resistor provides overcurrent detection.  

In the case of an overcurrent, the LTC4362-2 used in the 

DC1575B automatically tries to turn the internal MOSFET 

back on. An orange input LED indicates if the input supply 

is on while a green OUT LED indicates the gate is on and 

input is connected to the output.

Protection OV/OC/NV

The second selection at JP2 is OV/OC/NV protection which 

protects against overvoltage, overcurrent and negative 

voltage. The LTC4362 turns on an internal N-channel 

MOSFET when the input voltage is below the overvoltage 

threshold. A P-channel MOSFET is driven by the GATEP pin 

of the LTC4362 to protect the output against an inadvertent 

negative voltage connection at the input. An internal current 

sense resistor provides overcurrent detection. In the case 

of an overcurrent, the LTC4362-2 used in the DC1575B 

automatically retries to turn the internal MOSFET back 

on. The orange V

IN

 LED indicates if the input supply is on 

while a green OUT LED indicates the gate is on and input 

is passed over to the output. A red –V

IN

 LED indicates if 

a negative input voltage is present.

USB Protection

DC1575B also provides connection for USB protection.  

First connect a USB device with a USB cable at J2. Select 

the protection type at JP2 and match this with JP3. Select 

ENABLE at JP1. The USB source can then be connected 

at J1.

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