FP133 datasheet(7/10 Pages) FEELING

7 / 10 page

FP133

This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice.

No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product.

Website: http://www.feeling-tech.com.tw

Rev. 0.9

7/10

LOAD

RG1

RG2

VIN

VIP

VCC

GND

CSO

VIN+VIN-

1.25V

FPO

To Fault Protection

Circuits

Function Description

Current Shunt Regulator

The figure below shows the FP133 current shunt block, load current (IS) flowing from power

supply and a dropout voltage (VIN

+-V

-) at the sense resistor (R

S).

Assume internal NPN transistor collector current is same as emitter current (IO) and VIP is very

close to VIN, the FP133 transfer function is:

----- (1)

In this figure, the (VIN

+-V

-), is equal to I

S x RS and the current shunt output voltage (CSO) is

equal to IO x RL. The final transfer function for rail current measurement in this application is:

CSO





----- (2)



----- (3)

In FP133 internal circuits, the CSO output is connected to the shutdown comparator inverting

input. When the voltage of CSO is higher than the internal reference voltage (1.25V), the FPO pin is

switching from high to low state. This signal can be used for OCP protection control.

Note:

1. The minimum operating voltages of VCC, VIP and VIN are 2.7V. If these supply voltages are

lower than 2.7V, the transfer function at current shunt output (CSO) is no correct.

2. Do not force a VIN voltage that is 15V higher than VIP. This condition would generate a leakage

current and an incorrect voltage at FP133 output.



 



FP133 Datasheet(PDF) 7 Page - Feeling Technology Corp.

FP133 Datasheet(HTML) 7 Page - Feeling Technology Corp.

Html Pages

1 2 3 4 5 6 7 8 9 10

Datasheet Download

Link URL