XC9223/XC9224
Series
1A Driver Transistor Built-In Step-Down DC/DC Converters
ETR0509_007
■GENERAL
DESCRIPTION
☆GreenOperation-Compatible
The XC9223/XC9224 series are synchronous step-down DC/DC converters with a 0.21Ω (TYP.) P-channel driver transistor and a
synchronous 0.23Ω (TYP.) N-channel switching transistor built-in. A highly efficient and stable current can be supplied up to 1.0A by
reducing ON resistance of the built-in transistor. With a high switching frequency of 1.0MHz or 2.0MHz, a small inductor is selectable;
therefore, the XC9223/XC9224 series are ideally suited to applications with height limitation such as HDD or space-saving
applications. Current limit value can be chosen either 1.2A (MIN.) when the LIM pin is high level, or 0.6A (MIN.) when the LIM pin is
low level for using the power supply which current limit value differs such as USB or AC adapter. With the MODE/SYNC pin, the
XC9223/XC9224 series provide mode selection of the fixed PWM control or automatically switching current limit PFM/PWM control.
As for preventing unwanted switching noise, the XC9223/XC9224 series can be synchronized with an external clock signal within the
range of ± 25% toward an internal clock signal via the MODE/SYNC pin. For protection against heat damage of the ICs, the
XC9223/XC9224 series build in three protection functions: integral latch protection, thermal shutdown, and short-circuit protection.
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 1.8V or lower. The XC9223B/XC9224B series’ detector function monitors the discretional voltage by external resistors.
■APPLICATIONS
●HDD
●Notebook
computers
●CD-R
/ RW, DVD
●PDAs,
Portable communication modems
●Digital
cameras, Video recorders
●Various
general-purpose power supplies
■FEATURES
Input Voltage Range
Output Voltage Range
Oscillation Frequency
Output Current
Maximum Current
Limit
Controls
Protection Circuits
: 2.5V ~ 6.0V
: 0.9V ~ V
IN (set by FB pin)
: 1MHz, 2MHz (+15% accuracy)
: 1.0A
: 0.6A (MIN.) ~ 0.9A (MAX)
with LIM pin=’L’
: 1.2A (MIN.) ~ 2.0A (MAX.)
with LIM pin=’H’
: PWM/PFM or PWM by MODE pin
: Thermal shutdown
Integral latch method
Short-circuit protection
: 1ms (TYP.) internally set
: B type (with VD function)
D type (without VD function)
: 0.21Ω
Soft-Start Time
Voltage Detector
Built-in P-channel
MOSFET
Built-in Synchronous
: 0.23Ω
N-channel MOSFET
(No Schottky Barrier Diode Required)
High Efficiency
: 95% (V
IN
=5.0V, V
OUT
=3.3V)
Synchronized with an External Clock Signal
Ceramic Capacitor Compatible
Packages
: MSOP-10, USP-10B, SOP-8
* SOP-8 package is available for the XC9223D type only.
■TYPICAL
APPLICATION CIRCUIT
■TYPICAL
PERFORMANCE
CHARACTERISTICS
●
Efficiency vs. Output Current
XC9223B081Ax
XC9223B081Ax
100
90
80
Efficiency: EFFI (%)
70
60
50
40
30
20
10
0
1
10
100
Output Current: IOUT (mA)
1000
PW M/PFM
PW M
VOUT=1.5V
VOUT=3.3V
VIN=5V, FOSC=1MHz,
VIN=5V, FOSC=1M Hz, L =4.7uH(CDRH4D2 8C),
L=4.7μH (CDRH4D28C), CIN=10μF (ceramic), CL=10μF (ceramic)
CIN=10 uF(ceram i c), CL=1 0uF(cera m i c)
(*1) A capacitor of 2200pF
½
0.1μF is recommended to place at the C
DD
between the AGND
pin and the V
IN
pin.
Please refer to the page showing INSTRUCTION ON PATTERN LAYOUT for more detail.
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XC9223/XC9224
Series
■PIN
CONFIGURATION
VIN 1
VDIN 2
AGND 3
VDOUT 4
FB 5
10 PGND
9 LX
8 CE
7 MODE/SYNC
6 LIM
VIN 1
8 PGND
AGND 2
7 LX
FB 3
6 CE
MSOP-10
(TOP VIEW)
LIM 4
5 MODE/SYNC
SOP-8
(TOP VIEW)
FB 5
VDOUT 4
AGND 3
VDIN 2
VIN 1
6
7
8
9
LIM
MODE/SYNC
CE
LX
10 PGND
USP-10B
(BOTTOM VIEW)
■PIN
ASSIGNMENT
PIN NUMBER
MSOP-10 * USP-10B *
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
10
10
SOP-8 **
1
-
2
-
3
4
5
6
7
8
PIN NAME
V
IN
V
DIN
A
GND
V
DOUT
FB
LIM
MODE/SYNC
CE
Lx
P
GND
FUNCTION
Input
Voltage Detector Input
Analog Ground
VD Output
Output Voltage Monitor
Over Current Limit Setting
Mode Switch / External Clock Input
Chip Enable
Output of Internal Power Switch
Power Ground
* For MSOP-10 and USP-10B packages, please short the GND pins (pin #3 and 10)
** For SOP-8 package, please short the GND pins (pin# 2 and 8)
■FUNCTION
CHART
1. CE Pin Function
CE PIN
H
L
OPERATIONAL STATE
ON
OFF *1
*1: Except for a voltage detector block in the XC9224 series.
2. MODE Pin Function
MODE PIN
H
L
LIM PIN
H
L
FUNCTION
PWM Control
PWM/PFM Automatic Control
FUNCTION
Maximum Output Current: 1.0A
Maximum Output Current: 0.4A
3. LIM Pin Function
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XC9223/XC9224
Series
■PRODUCT
CLASSIFICATION
●Selection
Guide
●Ordering
Information
XC9223①②③④⑤⑥ <The common CE pin in the DC/DC block and the voltage detector block.>
XC9224B②③④⑤⑥ <No CE pin in the voltage detector block. (Constant operating of the voltage detector block) >
DESIGNATOR
①
DESCRIPTION
Transistor built-in,
Output voltage freely set (FB voltage),
Current Limit: 0.6A/1.2A
Reference Voltage
SYMBOL
B
D
0
8
1
2
A
⑤
Package
D
S
⑥
Device Orientation
R
L
DESCRIPTION
: With VD function
: Without VD function
: Fixed reference voltage
①=0, ②=8
: 1.0MHz
: 2.0MHz
: MSOP-10
: USP-10B
: SOP-8 (for the XC9223D type)
: Embossed tape, standard feed
: Embossed tape, reverse feed
②③
④
DC/DC Oscillation Frequency
3/25