9/28

XC6411/XC6412

Series

■

OPERATIONAL EXPLANATION

■

NOTES ON USE

1. Please use this IC within the stated absolute maximum ratings. The IC is liable to malfunction should the ratings be exceeded.

2. Where wiring impedance is high, operations may become unstable due to noise and/or phase lag depending on output

current.

3. As for the XC6412 series, internally achieved phase compensation makes a stable operation of the IC possible even when

prevent an undershoot or overshoot, we recommend that the output capacitor (CL) of about 0.1 to1.0μF be connected

close to the IC as possible.

4. The XC6412C series (USP-6C package) is under development.

<Dual Inputs>

The power input voltage pin of the regulator 1 and regulator 2 in the XC6411P/XC6412C series operate independently of

absolute, which makes the circuit structure efficiently.

<Short Protection Circuit>

The XC6411P/6412 series’ regulator offers short-circuit protection by means of a built-in foldback circuit. When the load current

reaches the current limit level, the fixed current limiter circuit operates and output voltage drops. As a result of this drop in

output voltage, the foldback circuit operates, the output voltage drops further and output current decreases. When the output

voltage pin is shorted, a current of about 50mA flows.

<EN2 Pin>

The regulator 2’s internal circuitry can be operated or shutdown via the signal from the EN2 pin with the XC6412 series. In so

If this IC is used with the correct specifications for the EN pin, the operational logic is fixed and the IC will operate normally.

However, supply current may increase as a result of through current in the IC's internal circuitry.

<Output Voltage Control>

The voltage, divided by resistors R11 & R12 for a regulator 1 and R21 & R22 for a regulator 2 is compared with the internal

stabilized by a system of negative feedback. The current limit circuit operates when the load current reaches the current limit

level.

* Diodes shown in the above circuit are ESD protection diodes and parasitic diodes.

●

XC6411P Series

●

XC6412B Series (SOT-26)

●

XC6412C Series (USP-6C)

*Preliminary

+

-

R11

R12

VIN1

VIN2

VOUT 1

VOUT 2

VSS

Voltage

Reference1

+

-

R21

R22

Current

Lim it2

+

-

R11

R12

VIN

EN2

VOUT 1

VOUT 2

VSS

Current

Lim it1

Voltage

Reference1

+

-

R21

R22

Current

Lim it2

Voltage

Reference2

ON/OFF

Control

VR2　Each Circuit

、

Current

Lim it1

Voltage

Reference2

+

-

R11

R12

VIN1

VIN2

VOUT 1

VOUT 2

VSS

Voltage

Reference1

+

-

R21

R22

Current

Lim it2

、

Current

Lim it1

Voltage

Reference2

EN2

ON/OFF

Control

VR2　Each Circuit