Functional Block Diagram

Functional Block Diagram

Control Part

LC5220

6

5

4

1

8

3

2

OPP

Logic

Gate Driver

UVLO

TSD

Band Gap

Reference

Regulator

OCP

Blanking

PWM

Control

Reference

Control

CC_REF

OCP_REF

Output

Control

Logic

TSD

UVLO

PWM

OCP

OPP

SLEEP

ENABLE

REG

VBB

REF

PWM

GND

Current

Detect

CC

OC

SEN

OUT

PWM _IN

SEN_IN

Pin List Table

Name

Number

Function

REG

1

Internal regulator supply, provides current to internal and external circuits;

connect a 0.1 μF bypass capacitor between this pin and GND.

PWM

2

Input for PWM control: to use internal PWM, connect a capacitor for setting

off-time; to use external PWM, connect to PWM signal source.

REF

3

Reference voltage input: sets peak output current of OUT pin (internal power

MOSFET) for internal PWM control, enables toggling output of OUT pin

(Enable function), and enables latched shutdown of output (Sleep function)

SEN

4

Output current detection: detects peak output current for internal PWM control,

and detects overcurrent for OCP; connect to current detection resistor.

OUT

5

Drain of internal power MOSFET.

VBB

6

Supply voltage, provides power to internal circuits through internal regulator.

GND

8

Ground pin.

―

7

Pin removed to increase creepage distance between high voltage pin and low

voltage pin.

1

2

3

4

8

6

5

GND

VBB

OUT

REG

PWM

REF

SEN

Pin-out Diagram

LC5223D and

LC5226D

6

SANKEN ELECTRIC CO., LTD.

LC5223D/26D-DS

Off-Line DC/DC LED Driver ICs

August 8, 2012