XC9509_1 Datasheet, PDF (1/41 Pages) Torex Semiconductor – Synchronous Step-Down DC/DC Converter with Built-In LDO Regulator in Parallel Plus Voltage Detector

XC9509 Series
Synchronous Step-Down DC/DC Converter
with Built-In LDO Regulator in Parallel Plus Voltage Detector
ETR1006_001
■GENERAL DESCRIPTION
The XC9509 series consists of a step-down DC/DC converter and a high-speed LDO regulator connected in parallel with the
DC/DC converter's output. A voltage detector is also built-in. Since the input for the LDO voltage regulator block comes
from the input power supply, it is suited for use with various applications.
The DC/DC converter block incorporates a P-channel driver transistor and a synchronous N-channel switching transistor.
With an external coil, diode and two capacitors, the XC9509 can deliver output currents up to 600mA at efficiencies over 90%.
The XC9509 is designed for use with small ceramic capacitors.
A choice of three switching frequencies are available, 300kHz, 600kHz, and 1.2MHz. Output voltage settings for the DC/DC
and VR are set-up internally in 100mV steps within the range of 0.9V to 4.0V (± 2.0%). For the VD, the range is of 0.9V to
5.0V (± 2.0%). The soft start time of the series is internally set to 5ms. With the built-in U.V.L.O. (Under Voltage Lock Out)
function, the internal P-channel driver transistor is forced OFF when input voltage becomes 1.4 V or lower. The functions of
the MODE pin can be selected via the external control pin to switch the DC/DC control mode and the disable pin to shut down
either the DC/DC block or the regulator block.
■APPLICATIONS
●CD-R / RW, DVD
●HDD
●PDAs, portable communication modem
●Cellular phones
●Palmtop computers
●Cameras, video recorders
■FEATURES
Input Voltage Range : 2.4V ~ 6.0V
Low ESR Capacitor : Ceramic capacitor compatible
VD Function
: Sense internally either VDD, DCOUT,
or VROUT. N-ch open drain output
Small Package
: MSOP-10, USP-10
<DC/DC Converter Block>
Output Voltage Range : 0.9V ~ 4.0V (Accuracy±2%)
Output Current
: 600mA (for MSOP-10 package)
400mA (for USP-10 package)
Control Method
: PWM or PWM/PFM Selectable
Oscillation Frequency : 300kHz, 600kHz, 1.2MHz
<Regulator Block>
Reglator Output
: Parallel Input to DC/DC Converter
Output Voltage Range : 0.9V ~ 4.0V (Accuracy±2%)
Current Limit
: 300mA
Dropout Voltage
: 80mV @ IOUT=100mA (VOUT=2.8V)
High Ripple Rejection : 60dB @1kHz (VOUT=2.8V)
■TYPICAL APPLICATION CIRCUIT
■TYPICAL PERFORMANCE
CHARACTERISTICS
XC9509Hxxxx
VIN=3.6V, Topr=25℃, L=4.7μH (CDRH4D28C),
CIN:4.7μF (ceramic), CL1:10μF (ceramic), CL2: 4.7μF (ceramic)
MSOP-10 (TOP VIEW)
* Please refer to the typical application circuit when
external components are selected.
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