MP3385A – 4-STRING WLED CONTROLLER WITH I

MP3385A Rev. 1.01

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15

8/29/2017

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500mV by the OCP2:0 bits in register 05H.

When the current exceeds the current limit

value, the IC latches off until the power is reset

or EN is toggled when operating in latch-off

mode if the OCPM bit = 0. The device restarts

when the current drops below the current limit

again if the OCPM bit = 1.

Short Inductor/Diode Protection

When the external inductor or diode is shorted,

the IC provides protection by detecting the

current flowing through the power MOSFET.

When the current sense voltage across the

sense resistor (connected between IS and GND)

hits the current protection threshold and lasts

for four switching cycles, the IC stops switching

and latches.

Thermal Shutdown Protection

To prevent the IC from operating at exceedingly

high

temperatures,

thermal

shutdown

is

implemented

to

detect

the

silicon

die

temperature.

When

the

die

temperature

down. The IC resumes normal operation when

the die temperature drops below the lower

threshold. Typically, the hysteresis value is

25°C.

Fault

Flag

Output

and

Fault

Register

Indicator

FT remains in an open-drain condition when the

LED driver is operating in a normal condition. It

is connected to VCC by an external 100kΩ

resistor and pulled to logic high when there is

no fault. FT goes to logic low if a fault occurs.

Set the corresponding fault bit in register 03H to

1.

I

I

master sends a 7-bit address followed by an

eighth read (Read: 1) or write (Write: 0) bit. The

bit indicates the register address to or from

which the data is written or read (see Figure 3).

Figure 3: The I