RT8289
5A, 32V, 500kHz Step-Down Converter
General Description
Features
z High Output Current up to 5A
The RT8289 is a step-down regulator with an internal Power
MOSFET. It achieves 5Aof continuous output current over
a wide input supply range with excellent load and line
regulation. Current mode operation provides fast transient
response and eases loop stabilization.
z Internal Soft-Start
z 100mΩ Internal Power MOSFET Switch
z Internal Compensation Minimizes External Parts
Count
z High Efficiency up to 90%
The RT8289 prorides protections such as cycle-by-cycle
current limiting and thermal shutdown. In shutdown mode,
the regulator draws 25A of supply current.
z 25μA Shutdown Current
z Fixed 500kHz Frequency
z Thermal Shutdown Protection
The RT8289 requires a minimum number of external
components, to proride a compact solution.
z Cycle-by-Cycle Over Current Protection
z Wide 5.5V to 32V Operating Input Range
z Adjustable Output Voltage from 1.222V to 26V
z Available in an SOP-8 (Exposed Pad) Package
z RoHS Compliant and Halogen Free
The RT8289 is available in a SOP-8 (Exposed Pad)
package.
Ordering Information
RT8289
Applications
z Distributive Power Systems
Package Type
SP : SOP-8 (Exposed Pad-Option 1)
z LCD TV
Lead Plating System
G : Green (Halogen Free and Pb Free)
Note :
z DSL Modems
z Pre-regulator for Linear Regulators
z Battery Charger
Richtek products are :
` RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
Pin Configurations
(TOP VIEW)
` Suitable for use in SnPb or Pb-free soldering processes.
8
BOOT
NC
SW
VIN
GND
EN
2
3
4
7
6
5
GND
NC
9
FB
SOP-8 (Exposed Pad)
Typical Application Circuit
1
8
7
5
V
IN
BOOT
RT8289
VIN
5.5V to 32V
C
10nF
L
C
BOOT
IN
10µH
4.7µF x 2
V
OUT
SW
5V/5A
Chip Enable
D
EN
R1
B550C
10k
C
OUT
Open
= Automatic Startup
4
47µFx2
(POSCAP)
6, Exposed Pad (9)
FB
GND
R2
3.16k
DS8289-01 March 2011
www.richtek.com
1
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
