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XCL104/XCL105

Series

■

OPERATIONAL EXPLANATION

＜

EN function / load disconnection function / bypass mode＞

When a "H" voltage (VENH) is input to the EN pin, the output voltage is raised by the start-up mode, and then normal operation

starts.

When the "L" voltage (VENL) is input to the EN pin, the IC enters the standby mode, and the current consumption is reduced to

the standby current ISTB.

The polarity of the parasitic diodes of the Pch synchronous switching FET and Pch synchronous switching FET in the standby

mode and the operation of the CL discharge function depending on the types.

The details of the operation for each type are as follows.

A/D/G/J types : Load disconnection function with CL discharge function

When the Nch driver FET and Pch synchronous switching FET are turned off, the CL discharge function operates.

When the CL discharge function operates, the charge on the output side is quickly discharged and the output voltage is reduced.

When the Nch driver FET and Pch synchronous switching FET are turned off and fix the polarity of the parasitic diode of the Pch

synchronous switching FET to anode: VOUT and cathode: Lx, the conduction from the input side to the output side is cut off.

The current consumption during this operation is the standby current ISTB (TYP. 0.0μA).

XCL105 C/F/M/L types : Load disconnection function without CL discharge function

Nch driver FET and Pch synchronous switching FET are turned off.

Even in standby mode, the VIN voltage is compared with the VOUT voltage, and the polarity of the parasitic diode for the Pch

synchronous switching FET is controlled so that the input and output sides do not connect through the parasitic diode of the Pch

synchronous switching FET.

Even if an external voltage higher than the VIN voltage is applied to the output side by controlling this parasitic diode, the input

side and the output side will not connect, and the output OR connection is possible.

The current consumption during this operation is the standby current ISTB (TYP. 0.16μA).

XCL105 B/E/H/K types : Bypass mode

When the Nch driver FET turned off and the Pch synchronous switching FET turned on, the resistance between the Lx and VOUT

becomes RLXP (TYP. 0.23Ω) and connects.

This operation allows current to be supplied to the output side even in the standby mode, enabling to drive the subsequent

devices.

The current consumption during this operation is the standby current ISTB (TYP. 0.0μA).

In standby mode (EN="L") Operation list

TYPE

Nch Driver FET

/ Pch Driver FET

VOUT

pin Voltage

CL

Discharge

ISTB (TYP.)

Applied Voltage to the VOUT pin

(EN=”L”)

A/D/G/J

OFF

/OFF

GND

Active

0.0μA

No

(CL Discharge Operation)

C/F/M/L

(Only XCL105)

OFF

/OFF

OPEN

-

0.16μA

Yes

B/E/H/K

(Only XCL105)

OFF

/ON

VIN

-

0.0μA

No

(Reverse Flow toward the input)