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Preliminary
June 26, 2003 Ver. 2
!
Externally Applied Reference Voltage (Vref)
!
Ceramic Capacitors Compatible
!
Input Voltage Range: 0.9V~10.0V
!
Oscillation Frequency: 300kHz, 100kHz (±15%)
!
PWM Control (XC9106)
PWM/PFM Automatic Switching Control (XC9107)
!
SOT-25 / USP-6B Packages
"
APPLICATIONS
#
Power Supply for LCD
#
PDAs
#
Cellular Phones
#
Palmtop Computers
#
Portable Audio Systems
#
Various Multi-function Power Supplies
"
GENERAL DESCRIPTION
The XC9106 / 07 series are step-up DC/DC controller ICs
with an externally applied reference voltage (Vref).
Output voltage will be set with external resistors (RFB1 and 2)
and Vref value. The series make it easy to control output
voltage externally and are suited to software applications that
need to vary voltage, such as LCD power supply for PDA.
Output will be stable no matter which load capacitors are
used but if a low ESR capacitor is used, RSENSE of about
0.1
will be required and phase compensation will be
achieved. This makes the use of ceramic capacitors much
easier, and allows for lower output ripple and reduced PCB
area requirements. Tantalum and electrolytic capacitors can
also be used, in which case, RSENSE becomes
unnecessary.
Oscillation frequencies of high clock, low ripple 300kHz and
low supply current 100kHz are available.
The XC9107 series are PWM/PFM automatic switching
controlled. Control switches from PWM to PFM during light
loads with the XC9107 and the series is highly efficient from
light loads to large output currents. By bringing the whole
circuit down while the series is in the stand-by mode
(CE/PWM pin : low), supply current can be reduced to less
than 1.0
μ
A.
"
FEATURES
Input Voltage Range:
Power Supply Voltage Range:
VREF Input Range:
Output Voltage:
0.9V ~ 10.0V
1.8V ~ 10.0V and more than Vref+0.7V
0.8V ~ 2.5V (
±
2.0%)
Vref x external split resistor ratio
VOUT=Vref x (RFB1+RFB2)/RFB2
300kHz, 100kHz
±
15%
more than 30mA
(VIN=3.3V, VOUT=20V, when peripheral
components are used as in the circuits below .)
Oscillation Frequency:
Output Current:
Controls:
PWM (XC9106)
PWM/PFM auto-switching (XC9107)
85% (TYP.)
ISTB=1
.
0
μ
A (MAX.)
High Efficiency:
Stand-by Current:
Load Capacitors:
Packages:
Low ESR capacitors compatible
SOT-25, USP-6B
"
TYPICAL APPLICATION CIRCUIT
"
TYPICAL APPLICATION PERFORMANCE
1
PWM Control, PWM/PFM Switching Control,
Step-up DC/DC Converters
Externally Applied Reference Voltage (Vref)
XC9106 / 07 Series
* RSENSE is of no use in light load (uncontinuous mode) applications such
as a small LCD, even using ceramic capacitor.
0
5
10
15
20
25
30
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Vref (V)
V
O
(
0
5
10
15
20
25
30
0.1
1
10
100
1000
I
OUT
(mA)
V
O
2.0V
Vref=0.8V
1.5V
2.5V
Circuit as left
V
DD
=V
IN
=3.3V, I
OUT
=30mA
XC9107D003MR
XC9107D003MR
Circuit as left
V
DD
=V
IN
=3.3V
L : 10
μ
H
SD : MA737
CFB : 27pF
Nch Power
MOS FET
2SK2159
V
IN
= 3.3V
RFB2 :
30k
RFB1 :
270k
V
OUT
= 8V~25V
I
OUT
= 30mA
D/A converter
Ceramic CL :
10
μ
F
CE/Vref
CIN
RSENSE : 100m
for Ceramic CL
*
0.8V~2.5V
3
2
1
5
4
Semiconductor Ltd.