RT8269 Datasheet, PDF (1/12 Pages) Richtek Technology Corporation – 3A, 24V, 400kHz Step-Down Converter

RT8269
3A, 24V, 400kHz Step-Down Converter
General Description
The RT8269 is a high voltage buck converter that can
support the input voltage range from 4.75V to 24V and the
output current can be up to 3A. Current Mode operation
provides fast transient response and eases loop
stabilization.
The chip provides protection functions such as cycle-by-
cycle current limiting and thermal shutdown protection.
In shutdown mode, the regulator draws 25μA of supply
current. The RT8269 is available in a SOP-8 (Exposed
Pad) surface mount package.
Ordering Information
RT8269
Package Type
SP : SOP-8 (Exposed Pad-Option 1)
Note :
Lead Plating System
G : Green (Halogen Free and Pb Free)
Richtek products are :
` RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
` Suitable for use in SnPb or Pb-free soldering processes.
Typical Application Circuit
Features
z Wide Operating Input Range : 4.75V to 24V
z Adjustable Output Voltage Range : 0.92V to 15V
z Output Current up to 3A
z 25μA Low Shutdown Current
z Power MOSFET : 0.1Ω
z High Efficiency up to 95%
z 400kHz Fixed Switching Frequency
z Stable with Low ESR Output Ceramic Capacitors
z Thermal Shutdown Protection
z Cycle-By-Cycle Over Current Protection
z RoHS Compliant and Halogen Free
Applications
z Distributive Power Systems
z Battery Charger
z DSL Modems
z Pre-regulator for Linear Regulators
Pin Configurations
(TOP VIEW)
BOOT
VIN
SW
GND
8
2
7
GND
3
9⁶
4
5
SS
EN
COMP
FB
SOP-8 (Exposed Pad)
V_IN
4.75V to 24V
Chip Enable
C_IN
10µFx2
2 _VIN
7 _EN
BOOT ¹
RT8269
SW ³
8 _SS
C_SS
0.1µF
9
(Exposed
4,
Pad)
GND
FB ⁵
COMP ⁶
C_{BOOT L1}
10nF 10µH
D1
B330A
C_C
2.7nF
R_C
22k
R1
25.8k
R2
10k
V_OUT
3.3V/3A
C_OUT
22µFx2
C_P
NC
DS8269-02 March 2011
www.richtek.com
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