RT8290 Datasheet, PDF (1/12 Pages) Richtek Technology Corporation – 3A, 23V, 340kHz Synchronous Step-Down Converter

RT8290
3A, 23V, 340kHz Synchronous Step-Down Converter
General Description
The RT8290 is a high efficiency synchronous step-down
DC/DC converter that can deliver up to 3A output current
from 4.5V to 23V input supply. The RT8290's current mode
architecture and external compensation allow the transient
response to be optimized over a wide range of loads and
output capacitors. Cycle-by-cycle current limit provides
protection against shorted outputs and soft-start eliminates
input current surge during start-up. The RT8290 also
provides output under voltage protection and thermal
shutdown protection. The low current (<3μA) shutdown
mode provides output disconnection, enabling easy power
management in battery-powered systems. The RT8290
is awailable in an SOP-8 (Exposed Pad) package.
Applications
z Industrial and Commercial Low Power Systems
z Computer Peripherals
z LCD Monitors and TVs
z Green Electronics/Appliances
z Point of Load Regulation of High-Performance DSPs,
FPGAs and ASICs.
Pin Configurations
(TOP VIEW)
BOOT
VIN
SW
GND
8
2
7
GND
3
6
9
4
5
SS
EN
COMP
FB
SOP-8 (Exposed Pad)
Features
z 4.5V to 23V Input Voltage Range
z 1.5% High Accuracy Feedback Voltage
z 3A Output Current
z Integrated N-MOSFET Switches
z Current Mode Control
z Fixed Frequency Operation : 340kHz
z Output Adjustable from 0.925V to 20V
z Up to 95% Efficiency
z Programmable Soft-Start
z Stable with Low-ESR Ceramic Output Capacitors
z Cycle-by-Cycle Over Current Protection
z Input Under Voltage Lockout
z Output Under Voltage Protection
z Thermal Shutdown Protection
z Thermally Enhanced SOP-8 (Exposed Pad) Package
z RoHS Compliant and Halogen Free
Ordering Information
RT8290
Package Type
SP : SOP-8 (Exposed Pad-Option 1)
Lead Plating System
G : Green (Halogen Free and Pb Free)
Z : ECO (Ecological Element with
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.
Typical Application Circuit
V_IN
4.5V to 23V
R_EN
100k
2 _VIN
C_IN
10µFx2
7 _EN
BOOT ¹
RT8290
SW ³
8 _SS
C_SS
0.1µF
9
(Exposed
4,
Pad)
GND
FB ⁵
COMP ⁶
C_{BOOT L1}
10nF ^10µH
C_C
3.9nF
R_C
6.8k
R1
26.1k
R2
10k
V_OUT
3.3V/3A
C_OUT
22µFx2
DS8290-02 March 2011
C_P
NC
www.richtek.com
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