XC9509 Datasheet, PDF (1/9 Pages) Torex Semiconductor – Synchronous Step-Down DC/DC Converter with Built-In LDO Regulator in Parallel plus Voltage Detector

XC9509 Series
September 30, 2003 Ver. 1
Synchronous Step-Down DC/DC Converter with Built-In LDO Regulator in Parallel plus Voltage Detector
! Input Voltage Range
! Output Voltage Range
! Switching Frequency
! Output Current
! Ultra Small Packages
! Ceramic Capacitor Compatible
2.4V ~ 6.0V
DC/DC 0.9 ~ 4.0V (±2%)
VR
0.9 ~ 4.0V (±2%)
VD
0.9 ~ 5.0V (±2%)
300kHz, 600kHz, 1.2MHz
DC/DC 600mA
VR
200mA
MSOP-10, USP-10
" APPLICATIONS
# HDD
# CD-R / RW, DVD
# PDAs, portable communication modem
# Cellular phones
# Palmtop computers
# Cameras, video recorders
" 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, 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 (± 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.
" FEATURES
Input Voltage Range :
Load Capacitors :
VD Function :
<DC/DC Converter>
Output Voltage Range :
Output Current :
Controls :
Oscillation Frequency :
<Regulator>
Output Voltage Range :
Current Limit
Dropout Voltage :
High Ripple Rejection
2.4V ~ 6.0V
Ceramic Capacitors Compatible
(Low ESR Capacitors)
Sense internally either
VDD, DCOUT, or VROUT.
Nch Open Drain Output
0.9 ~ 4.0V (±2%)
600mA
PWM Control
PWM, PWM / PFM Automatic
Switching External
300kHz, 600kHz, 1.2MHz
0.9 ~ 4.0V (±2%)
300mA
80mV @ IOUT=100mA (VOUT=2.8V)
60dB @1kHz (VOUT=2.8V)
" TYPICAL APPLICATION CIRCUIT
CIN1
CIN2
1
PGND
2 CE
3 PVDD
4 AVDD
5 VDOUT
SD
LX 10
DCOUT 9
VROUT 8
MODE 7
6
AGND
L
CL1
DCOUT
VROUT
CL2
MSOP-10
(TOP VIEW)
Data Sheet
" TYPICAL PERFORMANCE CHARACTERISTICS
XC9509Hxxxx
VIN=3.6V, Topr=25^OC, L:4.7uH(CDRH4D28C)
CIN:4.7uF(ceramic), CL1:10uF(ceramic), CL2: 1uF(ceramic)
100
DC/DC Efficiency
90
(DCOUT:2.2V, 1.2MHz)
80
70
60
50
40
30
20
PWM/PFM Switching Control
10
PWM Control
0
0.1
1
10
100
DC/DC Output Current IDOUT (mA)
1000
Semiconductor Ltd.
1