XC9510_2 Datasheet, PDF (1/36 Pages) Torex Semiconductor – Synchronous Step-Down DC/DC Converter With Built-In LDO Regulator Plus Voltage Detector

XC9510 Series
Synchronous Step-Down DC/DC Converter
with Built-In LDO Regulator In Series Plus Voltage Detector
ETR1007_001
■GENERAL DESCRIPTION
The XC9510 series consists of a step-down DC/DC converter and a high-speed LDO regulator connected in series with the
DC/DC converter's output. A voltage detector is also built-in. A highly efficient, low noise output is possible since the
regulator is stepped-down further from the DC/DC output.
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 XC9510 can deliver output currents up to 800mA at efficiencies over 90%.
The XC9510 is designed for use with small ceramic capacitors. A choice of three switching frequencies are available, 300
kHz, 600 kHz, and 1.2 MHz. Output voltage settings for the DC/DC is set-up internally in 100mV steps within the range of 1.6V
to 4.0V(±2.0%) and for the VR are set-up internally 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
operational states of the DC/DC and the regulator blocks can be changed by inputting three kinds of voltage level via the
CE/MODE pin. 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 the regulator block.
■APPLICATIONS
●CD-R / RW, DVD
●HDD
●PDAs, portable communication modem
●Cellular phones
●Palmtop computers
●Cameras, video recorders
■FEATURES
DC/DC Converter with Built-in LDO and VD Function
Input Voltage Range : 2.4V ~ 6.0V
Low ESR Capacitor : Ceramic capacitor compatible
VD Function
: Three Sensing Options for Either
VDD, DCOUT or VROUT
N-ch open drain output
Package
: SOP-8
<DC/DC Converter Block>
Output Voltage Range : 1.6V ~ 4.0V (Accuracy ±2%)
Output Current
: 800mA,
Controls
: PWM or PWM/PFM Selectable
Oscillation Frequency : 300kHz, 600kHz, 1.2MHz
<Regulator Block>
Regulator Input
: Serial Input from DC/DC output
Output Voltage Range : 0.9V ~ 4.0V (Accuracy±2%)
Current Limit
: 600mA
Dropout Voltage
: 160mV @ IOUT=200mA
(VOUT=2.8V)
High Ripple Rejection : 60dB @1kHz (VOUT=2.8V)
■TYPICAL APPLICATION CIRCUIT
■TYPICAL PERFORMANCE
CHARACTERISTICS
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