XC9510 Series
Preliminary
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Input Voltage Range
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Output Voltage Range
2.4V ~ 6.0V
DC/DC
VR
VD
0.9 ~ 4.0V (鹵2%)
0.9 ~ 4.0V (鹵2%)
0.9 ~ 5.0V (鹵2%)
800mA
600mA
October 28, 2003 Ver. 4
Synchronous Step-Down DC/DC Converter with Built-In LDO Regulator In Series plus Voltage Detector
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Switching Frequency
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Output Current
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Ultra Small Packages
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Ceramic Capacitor Compatible
300kHz, 600kHz, 1.2MHz
DC/DC
VR
SOP-8
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APPLICATIONS
"
CD-R / RW, DVD
"
HDD
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PDAs, portable communication modem
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Cellular phones
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Palmtop computers
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Cameras, video recorders
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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 and VR are set-up internally in
0.1V steps within the range of 0.9V to 4.0V (鹵 2.0%). For the VD, the
range is of 0.9V to 5.0V (鹵 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.
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FEATURES
Input Voltage Range :
Load Capacitors :
2.4V ~ 6.0V
Ceramic Capacitors Compatible
(Low ESR Capacitors)
VD Function :
Detects output voltage from the VDOUT pin
while sensing either VDD, DCOUT,
or VROUT internally.
Nch Open Drain Output
<DC/DC Converter>
Output Voltage Range : 0.9 ~ 4.0V (Accuracy
鹵2%)
Output Current :
Controls :
800mA
PWM Control
PWM, PWM / PFM Automatic
Switching External
Oscillation Frequency : 300kHz, 600kHz, 1.2MHz
<Regulator>
Output Voltage Range : 0.9 ~ 4.0V (Accuracy
鹵2%)
Current Limit
Dropout Voltage :
High Ripple Rejection
600mA
240mV @ IOUT=300mA (VOUT=2.8V)
60dB @1kHz (VOUT=2.8V)
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TYPICAL APPLICATION CIRCUIT
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TYPICAL PERFORMANCE CHARACTERISTICS
XC9510Hxxxx
DC/DC Efficiency (DCOUT:3.4V, 1.2MHz), VR Efficiency (VROUT:3.0V)
VIN=5.0V, Topr=25 C, L:4.7uH(CDRH4D28C),
CIN:4.7uF(ceramic), CL1:10uF(ceramic), CL2:1uF(ceramic)
100
O
90
( )
SD
1
2
3
CIN
4
VDOUT
AGND
5
LX
PGND
CE/
DCOUT
MODE
VDD
VROUT
8
7
6
DCOUT
Efficiency EFFI (%)
L
CL1
80
70
60
50
40
30
20
PWM/PFM switching control
PWM control
VROUT
CL2
SOP-8 (Top View)
10
0
0.1
1
10
100
DC/DC Output Current IDOUT
VR Output Current IROUT (mA)
1000
Semiconductor Ltd.
Data Sheet
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