RT8015

2

DS8015-03

March 2011

www.richtek.com

Functional Pin Description

Pin No.

Pin Name

Pin Function

1

SHDN/RT

Oscillator Resistor Input. Connecting a resistor to ground from this pin sets the

2,

9 (Exposed Pad)

GND

Signal Ground. All small-signal components and compensation components should

connect to this ground, which in turn connects to PGND at one point. The exposed

pad must be soldered to a large PCB and connected to GND for maximum power

dissipation.

3

LX

Internal Power MOSFET Switches Output. Connect this pin to the inductor.

4

PGND

Power Ground. Connect this pin close to the (

5

PVDD

Power Input Supply. Decouple this pin to PGND with a capacitor.

6

VDD

equal to PVDD.

7

FB

Feedback Pin. Receives the feedback voltage from a resistive divider connected

across the output.

8

COMP

Error Amplifier Compensation Point. The current comparator threshold increases

with this control voltage. Connect external compensation elements to this pin to

stabilize the control loop.

Typical Application Circuit

Note : Using all Ceramic Capacitors

L1 (uH)

R1 (k

Ω)

R2 (k

Ω)

3.3V

2.2

22

750

240

13

1

2.5V

2.2

22

510

240

13

1

1.8V

1.0

22

300

240

7.5

1.5

1.2V

1.0

22

120

240

7.5

1.5

Recommended Component for Different Output Voltage Applications

6

VDD

PVDD

5

RT8015

2.6V to 5.5V

4

PGND

SHDN/RT

1

LX

3

COMP

FB 7

8

GND

2,

Exposed

Pad (9)

332k

22uF

L1

2.2uH

R1

510k

R2

240k

22uF

1nF

2.5V/2A