RT8259 Datasheet, PDF (1/13 Pages) Richtek Technology Corporation – 1.2A, 24V, 1.4MHz Step-Down Converter

RT8259
1.2A, 24V, 1.4MHz Step-Down Converter
General Description
The RT8259 is a high voltage buck converter that can support
the input voltage range from 4.5V to 24V and the output
current can be up to 1.2A. Current Mode operation provides
fast transient response and eases loop stabilization.
The chip also provides protection functions such as cycle-
by-cycle current limiting and thermal shutdown protection.
The RT8259 is available in a SOT-23-6 and TSOT-23-6
packages.
Ordering Information
RT8259
Package Type
E : SOT-23-6
J6 : TSOT-23-6
Lead Plating System
G : Green (Halogen Free and Pb Free)
Note :
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.
Marking Information
For marking information, contact our sales representative
directly or through a Richtek distributor located in your
area.
Features
z Wide Operating Input Voltage Range : 4.5V to 24V
z Adjustable Output Voltage Range : 0.8V to 15V
z 1.2A Output Current
z 0.3Ω Internal Power MOSFET Switch
z High Efficiency up to 92%
z 1.4MHz Fixed Switching Frequency
z Stable with Low ESR Output Ceramic Capacitors
z Thermal Shutdown
z Cycle-By-Cycle Over Current Protection
z RoHS Compliant and Halogen Free
Applications
z Distributed Power Systems
z Battery Charger
z Pre-Regulator for Linear Regulators
z WLEDDrivers
Pin Configurations
(TOP VIEW)
PHASE VIN EN
6
5
4
23
BOOT GND FB
SOT-23-6/TSOT-23-6
Typical Application Circuit
V_IN
4.5V to 24V
C1
10µF
5 _VIN
BOOT ¹
RT8259
PHASE ⁶
Chip Enable
4 _EN
Open =
Automatic Startup
GND
2
FB ³
CB
10nF
L1
4.7µH
D1
B230A
V_OUT
3.3V
R1
62k
R2
19.6k
C2
22µF
DS8259-03 March 2011
www.richtek.com
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