®
RT6207A/B
5A, 18V, 650kHz, ACOT
TM
Synchronous Step-Down Converter
General Description
The RT6207A/B is a high-performance 650kHz, 5A step-
down regulator with internal power switches and
synchronous rectifiers. It features quick transient response
using its Advanced Constant On-Time (ACOT
TM
) control
architecture that provides stable operation with small
ceramic output capacitors and without complicated
external compensation, among other benefits. The input
voltage range is from 4.5V to 18V and the output is
adjustable from 0.7V to 8V. The proprietary ACOT
TM
control
improves upon other fast response constant on-time
architectures, achieving nearly constant switching
frequency over line, load, and output voltage ranges. Since
there is no internal clock, response to transients is nearly
instantaneous and inductor current can ramp quickly to
maintain output regulation without large bulk output
capacitance. The RT6207A/B is stable with and optimized
for ceramic output capacitors. With internal 60mΩ switches
and 22mΩ synchronous rectifiers, the RT6207A/B displays
excellent efficiency and good behavior across a range of
applications, especially for low output voltages and low
duty cycles. Cycle-by-cycle current limit provides
protection against shorted outputs, input under-voltage
lock-out, externally-adjustable soft-start, output under- and
over-voltage protection, and thermal shutdown provide safe
and smooth operation in all operating conditions. The
RT6207A/B is available in the UQFN-13JL 2x3 (FC)
package, with exposed thermal pad.
Features
Fast Transient Response
Advanced Constant On-Time (ACOT
TM
) Control
4.5V to 18V Input Voltage Range
Adjustable Output Voltage from 0.7V to 8V
5A Output Current
Ω
60mΩ Internal High-Side N-MOSFET and 22mΩ
Ω
Internal Low-Side N-MOSFET
Steady 650kHz Switching Frequency
Up to 95% Efficiency
Optimized for All Ceramic Capacitors
Externally-Adjustable, Pre-Biased Compatible Soft-
Start
Cycle-by-Cycle Current Limit
Input Under-Voltage Lockout
Output Over- and Under-Voltage Protection
Power Good Output
Externally-Adjustable, Pre-Biased Compatible Soft-
Start
Thermal Shutdown
Applications
Industrial and Commercial Low Power Systems
Computer Peripherals
LCD Monitors and TVs
Green Electronics/Appliances
Point of Load Regulation for High-Performance DSPs,
FPGAs, and ASICs
Simplified Application Circuit
V
IN
C
IN
V
PVCC
Enable
C
SS
R
PG
PGOOD
EN
SS
FB
PVCC
GND
C
PVCC
V
PVCC
R2
RT6207A/B
SW
VIN
BOOT
L
V
OUT
C
BOOT
C
FF
R1
C
OUT
Copyright
©
2015 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS6207A/B-02
December 2015
www.richtek.com
1
RICHTEK [ RICHTEK TECHNOLOGY CORPORATION ]
