RS8407
1.5MHz, 2A, Synchronous Step-Down
DC/DC Converter
DESCRIPTION
FEATURES
The RS8407 is a high efficiency monolithic synchronous
buck regulator using a constant frequency, current mode
architecture. The device is available in an adjustable
version. Supply current with no load is 45uA and drops to
<1uA in shutdown. The 2.7V to 5.5V input voltage range
makes the RS8407 ideally suited for single Li-Ion, two to
four AA battery-powered applications. 100% duty cycle
provides low dropout operation, extending battery life in
portable systems. In power saving mode, 45uA quiescent
current is very suitable for DSP/MCU in standby
operation; and in PWM mode, low output ripple voltage is
good enough for noise sensitive applications. The two
modes can be automatically switched according to the
load current.
High Efficiency: Up to 95%
1.5MHz Constant Switching Frequency
Integrated Main switch and synchronous rectifier.
No Schottky Diode Required
Shutdown Current: <1μA
2.7V to 5.5V Input Voltage Range
Output Voltage as Low as 0.6V
100% Duty Cycle in Dropout
Quiescent Current : 45μA (TYP.)
Slope Compensated Current Mode Control for
Excellent Line and Load Transient Response
Short Circuit Protection
<1uA Shutdown Current
APPLICATIONS
Switching frequency is internally set at 1.5MHz, allowing
the use of small surface mount inductors and capacitors.
The internal synchronous switch increases efficiency and
eliminates the need for an external Schottky diode. Low
output voltages are easily supported with the 0.6V
feedback reference voltage. The RS8407 is available in a
small SOT-23-5 package and SOT-23-6 package.
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BLOCK DIAGRAM
Tel: 886-66296288‧Fax: 886-29174598‧ http://www.princeton.com.tw‧2F, No. 233-1, Baociao Rd., Sindian Dist., New Taipei City 23145, Taiwan