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XCL205/XCL206/XCL207 Series

■BLOCK DIAGRAM

1) XCL205 / XCL206 / XCL207 series A Type

NOTE: The XCL205 offers a fixed PWM control, a signal from CE/MODE Control Logic to PWM/PFM Selector is fixed to "L" level inside.

The XCL206 control scheme is PWM/PFM automatic switching, a signal from CE/MODE Control Logic to PWM/PFM Selector is fixed to

"H" level inside.

The diodes placed inside are ESD protection diodes and parasitic diodes.

2) XCL205 / XCL206 / XCL207 series B/C/G Type

3) XCL205 / XCL206 / XCL207 series F Type

CE/MODE

R2

R1

Error

Amp.

Vref with

Soft Start,

CE

Phase

Compensation

Current Feedback

Current Limit

PWM

Comparator

Logic

Synch

Buffer

Drive

R3

R4

UVLO

UVLO Cmp

Ramp Wave

Generator

OSC

Lx

VSS

VIN

VOUT

CE/MODE

Control

Logic

VSHORT

FB

CFB

Inductor

VSS

L2

L1

PWM/PFM

Selector

CE/

CE/MODE

R2

R1

Error

Amp.

Vref with

Soft Start,

CE

Phase

Compensation

Current Feedback

Current Limit

PWM

Comparator

Logic

Synch

Buffer

Drive

R3

R4

UVLO

UVLO Cmp

Ramp Wave

Generator

OSC

Lx

VSS

VIN

VOUT

CE/MODE

Control

Logic

VSHORT

FB

CFB

Inductor

VSS

L2

L1

PWM/PFM

Selector

CE/

CE/MODE

Error

Amp.

Vref with

Soft Start,

CE

Phase

Compensation

Current Feedback

Current Limit

PWM

Comparator

Logic

Synch

Buffer

Drive

R3

R4

UVLO

UVLO Cmp

Ramp Wave

Generator

OSC

Lx

VSS

VIN

FB

CE/MODE

Control

Logic

VSHORT

FB

Inductor

VSS

L2

L1

PWM/PFM

Selector