XC9223/9224 Series
1A Driver Transistor Built-In Step-Down DC/DC Converters
Preliminary
October 7, 2004 V2
Green Operation Compatible
APPLICATIONS
Step-Down DC/DC Converters
HDD
Built-in P-channel MOSFET
: 0.23Ω
Notebook computers
Built-in Synchronous N-channel MOSFET
: 0.25Ω
CD-R / RW, DVD
(No Schottky Barrier Diode Required)
PDAs, Portable communication modems
High Efficiency
Oscillation Frequency:
Digital cameras, Video recorders
: 94% (VIN=5.0V, VOUT=3.3V)
: 1.0MHz, 2.0MHz
Various general-purpose power supplies
(Small Inductor for High Frequency Selectable)
Synchronized with an External Clock Signal
Ceramic Capacitor Compatible
MSOP-10 / USP-10 Packages
GENERAL DESCRIPTION
FEATURES
The XC9223/9224 series are synchronous step-down DC/DC converters
with a 0.23Ω (TYP.) P-channel driver transistor and a synchronous
0.25Ω (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 XC9223/9224 series are ideally suited to
applications with height limitation such as HDD or space-saving
applications.
Current limit value can be chosen either 1.5A (MIN.) when the LIM pin is
high level, or 0.5A (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 XC9223/9224 series provide mode selection of
the fixed PWM control or automatically switching current limit PFM/PWM
control. As for preventing unwanted switching noise, the XC9223/9224
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 XC9223/9224 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 series’ detector function monitors the discretional voltage by external
resistors.
Input Voltage Range
: 2.2V ~ 6.0V
Output Voltage Range
: 0.8V ~ VIN
Can be set freely with 0.8V (+2%) of
reference voltage by the external resistors.
Oscillation Frequency
: 1MHz, 2MHz ( ± 15% accuracy)
Output Current
: 1.0A
Maximum Current Limit
: 0.5A (MIN.) when LIM pin=’L’
: 1.5A (MIN.) when LIM pin=’H’
Controls
: PWM/PFM externally switching
: Synchronized with an external clock signal
Protection Circuits
: Thermal shutdown
: Integral latch method (over current limit)
: Short-circuit protection
TYPICAL APPLICATION CIRCUIT
Soft-Start Time
: 3mS (TYP.) internally set
Voltage Detector
: 0.712V detect, N-ch open drain output
TYPICAL PERFOMANCE CHARACTERICSTICS
Efficiency vs. Output Current
VIN=5.0V, FOSC=2.0MHz
CIN
VDIN
VDOUT
1
VIN
2
VDIN
3
AGND
4
VDOUT
5
FB
PGND
10
LX
9
CE
MODE/
SYNC
LIM
8
7
6
L
CE
MODE/SYNC
LIM
VOUT
CFB
RFB1
CL
(ceramic)
Efficiency: EFFI (%)
VIN
L=2.0µH(CDRH4D28C), CIN=10µF(ceramic), CL=10µF(ceramic)
RFB2
100
90
80
70
60
50
40
VOUT=3.3V
VOUT=1.5V
30
20
10
0
Output Current: IOUT (mA)
1
Data Sheet
1
10
100
1000
10000
DC000019
XC9223/9224 Series
1A Driver Transistor Built-In Step-Down DC/DC Converters
Preliminary
PIN CONFIGURATION
VIN 1
1 VIN
PGND 10
10 PGND
VDIN 2
9 LX
LX 9
2 VDIN
AGND 3
8 CE
CE 8
3 AGND
VDOUT 4
4 VDOUT
MODE/SYNC 7
7 MODE/SYNC
FB 5
6 LIM
5 FB
LIM 6
MSOP-10
(TOP VIEW)
USP-10
(BOTTOM VIEW)
* Please short the AGND pin and the PGND pin
(pin no. 3 and 10) before use.
* For mounting intensity and heat dissipation, please
refer to recommended mounting pattern and
recommended metal mask when soldering the pad
of USP-10.
PIN ASSIGNMENT
PIN NUMBER
PIN NAME
FUNCTIONS
1
VIN
Input
2
VDIN
Voltage Detector Input
3
AGND
Analog Ground
4
VDOUT
VD Output
5
FB
Output Voltage Monitor
6
LIM
Over Current Limit Setting
7
MODE/SYNC
Mode Switch / External Clock Input
8
CE
Chip Enable
9
LX
Switch
10
PGND
Power Ground
PRODUCT CLASSIFICATION
Ordering Information
XC9223B 12345
XC9224B 12345
DESIGNATOR
1
2
<No CE pin in the VD block.
(The VD block is constantly operated.)>
DESCRIPTION
SYMBOL
Reference Voltage
08
: Fixed voltage
1
: 1.0 MHz
2
: 2.0 MHz
A
: MSOP-10
D
: USP-10
R
: Embossed tape, Standard feed
L
: Embossed tape, Reverse feed
3
DC/DC Oscillation Frequency
4
Package
5
Data Sheet
<The CE pin is commonly used in the DC/DC block and the VD block.>
DESCRIPTION
Device Orientation
2
DC000019
XC9223/9224 Series
1A Driver Transistor Built-In Step-Down DC/DC Converters
Preliminary
PACKAGING INFORMATION
MSOP-10
USP-10
0.15+0.01
2.6+0.06
2.7+0.05
MAX 0.6
0.30
.
3.00+0.10
0.25+0.06
4.90+0.10
-
3.00+0.10
-
0.53+0.10
-
-
0.15
O
-
(1.50)
0.86+0.05
-
(0.5)
2.30
(0.5)
0.2+0.05
Soldering fillet surface is not formed
because the sides of the pins are not plated.
0.075+0.025
-
(0.2)
.
(0.1)
0~ 5
BLOCK DIAGRAM
VIN
LIM
Error Amp.
FB
Current Limit
PFM
Comparator
PWM
Logic
Buffer
Driver
Current
Feedback
CE
MODE/
SYNC
LX
Vref with
Soft-Start,
CE
PGND
Ramp Wave
Generator,
OCS
PMW/PFM
Thermal
Shutdown
AGND
VD
VDOUT
VDIN
Data Sheet
3
DC000019
XC9223/9224 Series
1A Driver Transistor Built-In Step-Down DC/DC Converters
Preliminary
ABSOLUTE MAXIMUM RATINGS
Ta=25 OC
PARAMETER
SYMBOL
RATINGS
UNITS
VIN Pin Voltage
VIN
- 0.3 ~ 6.5
V
VDIN Pin Voltage
VDIN
- 0.3 ~ VDD + 0.3
V
VDOUT Pin Voltage
VDOUT
- 0.3 ~ VDD + 0.3
V
VDOUT Pin Current
IDOUT
50
mA
FB Pin Voltage
VFB
- 0.3 ~ VDD + 0.3
V
LIM Pin Voltage
VLIM
- 0.3 ~ VDD + 0.3
V
MODE/SYNC Pin Voltage
VMODE/SYNC
- 0.3 ~ VDD + 0.3
V
CE Pin Voltage
VCE
- 0.3 ~ VDD + 0.3
V
LX Pin Voltage
VLX
- 0.3 ~ VDD + 0.3
V
LX Pin Current
ILX
2000
mA
Power Dissipation
MSOP-10
USP-10
Pd
350*
150
mW
Operating Temperature Range
Topr
- 40 ~ + 85
O
Storage Temperature Range
Tstg
- 55 ~ + 125
O
C
C
* When implemented on a PCB.
Data Sheet
4
DC000019
XC9223/9224 Series
1A Driver Transistor Built-In Step-Down DC/DC Converters
Preliminary
ELECTRICIAL CHARACTERISTICS
XC9223B081xx
PARAMETER
Topr=25OC
SYMBOL
CONDITIONS
MIN.
TYP.
MAX.
UNIT
CIRCUIT
Input Voltage
VIN
2.2
-
6.0
V
-
FB Voltage
VFB
0.784
0.800
0.816
V
-
Output Voltage Range
VOUTSET
0.8
-
VIN
V
-
Maximum Output Current (*1)
IOUTMAX
1.0
-
-
A
-
-
1.8
-
V
-
FB=VFB x 0.9
-
380
-
µA
-
U.V.L.O. Voltage (*2)
VUVLO
Supply Current 1
IDD1
FB=VFB x 0.9, Voltage which Lx pin voltage
holding “L” level
Supply Current 2
IDD2
FB=VFB x 1.1 (Oscillation stops)
-
30
-
µA
-
Stand-by Current
ISTB
CE=0V
-
-
1.0
µA
-
Oscillation Frequency
FOSC
0.85
1.00
1.15
MHz
-
0.75
-
1.25
MHz
--
External Clock Signal
Synchronized Frequency
Connected to external components,
IOUT=10mA
Connected external components,
SYNCOSC
IOUT=10mA, apply an external clock signal to
the MODE/SYNC
External Clock Signal Duty
SYNCDTY
25
-
75
%
-
Maximum Duty Ratio
MAXDTY
FB=VFB x 0.9
100
-
-
%
-
Minimum Duty Ratio
MINDTY
FB=VFB x 1.1
-
-
0
%
-
-
150
-
mA
-
-
94
-
%
-
-
0.23
-
Ω
-
-
0.25
-
Ω
-
0.5
-
-
A
-
1.5
-
-
A
-
PFM Switch Current
IPFM
Efficiency (*3)
EFFI
Lx SW “H” On Resistance (*4)
RLxH
Lx SW “L” On Resistance (*4)
RLxL
Current Limit 1
ILIM1
Current Limit 2
ILIM2
Integral Latch Time (*5, *6)
TLAT
Short Detect Voltage
VSHORT
Soft-Start Time
TSS
Connected to external components,
MODE/SYNC=0V, IOUT=0.1mA
Connected to external components,
CE=VIN=5.0V, VOUT=3.3V, IOUT=200mA
FB=VFB x 0.9, ILx=100mA
LIM=0V, FB=VFB x 0.9
Current which Lx starts oscillation
LIM=VIN, FB=VFB x 0.9
Current which Lx starts oscillation
FB=VFB x 0.9, Short Lx by 1Ω resistance
-
6
-
ms
-
FB Voltage which Lx becomes “L”
-
0.4
-
V
-
-
3
-
ms
-
C
-
C
-
Connected to external components,
CE=0VDVIN, IOUT=1mA
Thermal Shutdown Temperature
TTSD
-
150
-
O
Hysteresis Temperature
THYS
-
20
-
O
1.2
-
-
V
-
-
-
0.4
V
-
FB=VFB x 0.9, Voltage which Lx becomes “H”
CE “H” Voltage
VCEH
CE “L” Voltage
VCEL
MODE/SYNC “H” Voltage
VMODE/SYNCH
1.2
-
-
V
-
MODE/SYNC “L” Voltage
VMODE/SYNCL
-
-
0.4
V
-
LIM “H” Voltage
VLIMH
1.2
-
-
V
-
LIM “L” Voltage
VLIML
-
-
0.4
V
-
CE “H” Current
ICEH
VIN=CE=6.0V
-
CE “L” Current
ICEL
VIN=6.0V, CE=0V
MODE/SYNC “H” Current
IMODE/SYNCH
VIN=CE=MODE/SYNC=6.0V
MODE/SYNC “L” Current
IMODE/SYNCL
VIN=CE=6.0V, MODE/SYNC=0V
LIM “H” Current
ILIMH
VIN=CE=LIM=6.0V
LIM “L” Current
ILIML
VIN=CE=6.0V, LIM=0V
FB “H” Current
IFBH
VIN=CE=FB=6.0V
FB “L” Current
IFBL
VIN=CE=6.0V, FB=0V
Lx SW “H” Leak Current
ILxH
VIN=LX=6.0V, VCE=0V
Lx SW “L” Leak Current (*7)
ILxL
VIN=6.0V, LX=CE=0V
Data Sheet
when voltage applied to CE
FB=VFB x 0.9, Voltage which Lx becomes “L”
when voltage applied to CE
5
-
-
0.1
µA
-0.1
-
-
µA
-
-
-
0.1
µA
-
-0.1
-
-
µA
-
-
-
0.1
µA
-
-0.1
-
-
µA
-
-
-
0.1
µA
-
-0.1
-
-
µA
-
-
-
1.0
µA
-
-1.0
-
-
µA
DC000019
XC9223/9224 Series
1A Driver Transistor Built-In Step-Down DC/DC Converters
Preliminary
ELECTRICIAL CHARACTERISTICS (Continued)
XC9223B081xx (Continued)
VOLTAGE DETECTOR
PARAMETER
Topr=25OC
SYMBOL
CONDITIONS
MIN.
TYP.
MAX.
UNIT
CIRCUIT
Detect Voltage
VDF
Voltage which VDOUT becomes ”H”D”L”
-
0.700
-
V
-
Release Voltage
VDR
Voltage which VDOUT becomes ”L”D”H”
-
0.745
-
V
-
Hysteresis Voltage
VHYS
VHYS=(VDR-VDF)/VDF x 100
-
6
-
%
-
Output Current
IDOUT
VDIN=VDF x 0.9, apply 0.5V to VDOUT
-
2.5
-
mA
-
Delay Time
TDLY
Time until VDOUT becomes “L” D “H”
-
2
-
ms
-
VDIN “H” Current
IVDINH
VIN=CE=VDIN=6.0V
-
-
0.1
µA
-
VDIN “L” Current
IVDINL
VIN=CE=6.0V, VDIN=0V
-0.1
-
-
µA
-
VDOUT “H” Current
IVDOUTH
VIN=VDIN=VDOUT=6.0V
-
-
1.0
µA
-
VDOUT “L” Current
IVDOUTL
VIN=VDIN=6.0V, VDOUT=0V
-1.0
-
-
µA
-
Test Condition: Unless otherwise stated, VIN=3.6V.
NOTE:
*1: When the difference between the input and the output is small, some cycles may be skipped completely before current maximizes.
If current is further pulled from this state, output voltage will decrease because of P-ch driver ON resistance.
*2: Including hysteresis operating voltage range.
*3: EFFI = { ( output voltage x output current ) / ( input voltage x input current) } x 100
*4: On resistance (Ω)= Lx pin measurement voltage / 100mA
*5: Time until it short-circuits Lx with GND through 1Ω of resistance from a state of operation and is set to Lx=Low from current limit pulse generating.
*6: Integral latch circuit: Latch time may become longer and latch operation may not work when VIN is 3.0V or more.
*7: When temperature is high, a current of approximately 50µA (maximum) may leak.
OPERATIONAL EXPLANATION
Each unit of the XC9223/9224 series consists of a reference voltage source, a ramp wave circuit, error amplifier, PWM comparator, phase compensation
circuit, output voltage adjustment resistors, P-channel MOS driver transistor, N-channel MOS synchronous rectification switching transistor, current limiter
circuit, U.V.L.O. circuit and others. The series compares, using the error amplifier, the internal reference voltage to the CE pin with the voltage fedback from
the VOUT pin via resistors RFB1 and RFB2. Phase compensation is performed on the resulting error amplifier output, to input a signal to the PWM
comparator to determine the turn-on time during PWM operation. The PWM comparator compares, in terms of voltage level, the signal from the error
amplifier with the ramp wave from the ramp wave circuit, and delivers the resulting output to the buffer driver circuit to cause the Lx pin to output a switching
duty cycle. This process is continuously performed to ensure stable output voltage. The current feedback circuit monitors the P-channel MOS driver
transistor current for each switching operation, and modulates the error amplifier output signal to provide multiple feedback signals. This enables a stable
feedback loop even when a low ESR capacitor, such as a ceramic capacitor, is used, ensuring stable output voltage.
<Reference Voltage Source>
The reference voltage source provides the reference voltage to ensure stable output voltage of the DC/DC converter.
<Ramp Wave Circuit>
The ramp wave circuit determines switching frequency. The frequency is fixed internally and can be selected from 1.0MHz and 2.0MHz.
generated in this circuit are used to produce ramp waveforms needed for PWM operation, and to synchronize all the internal circuits.
Clock pulses
<Error Amplifier>
The error amplifier is designed to monitor output voltage. The amplifier compares the reference voltage with the feedback voltage divided by the internal
resistors (RFB1 and RFB2). When a voltage lower than the reference voltage is fed back, the output voltage of the error amplifier increases. The gain and
frequency characteristics of the error amplifier output are fixed internally to deliver an optimized signal to the mixer.
Data Sheet
6
DC000019
XC9223/9224 Series
1A Driver Transistor Built-In Step-Down DC/DC Converters
Preliminary
OPERATIONAL EXPLANATION (Continued)
<Current Limit>
The current limiter circuit of the XC9223/9224 series monitors the current flowing through the P-channel MOS driver transistor connected to the Lx pin, and
features a combination of the constant-current type current limit mode and the operation suspension mode. For the current limit values, please select the
values either from 1.5A (MIN.) when the LIM pin is high level or 0.5A (MIN.) when the LIM pin is low level.
1 When the driver current is greater than a specific level, the constant-current type current limit function operates to turn off the pulses from the Lx pin at
any given time.
2 When the driver transistor is turned off, the limiter circuit is then released from the current limit detection state.
3 At the next pulse, the driver transistor is turned on. However, the transistor is immediately turned off in the case of an over current state.
4 When the over current state is eliminated, the IC resumes its normal operation.
The IC waits for the over current state to end by repeating the steps 1 through 3. If an over current state continues for several msec and the above three
steps are repeatedly performed, the IC performs the function of latching the OFF state of the driver transistor, and goes into operation suspension mode.
After being put into suspension mode, the IC can resume operation by turning itself off once and then starting it up using the CE pin, or by restoring power to
the VIN pin. Integral latch time may be released from a current limit detection state because of the noise. Depending on the state of a substrate, it may
result in the case where the latch time may become longer or the operation may not be latched. Please locate an input capacitor as close as possible.
Limit < # mS
Limit > # mS
Current Limit LEVEL
IDOUT
0mA
DCOUT
VSS
LX
CE
Restart
VIN
<Thermal Shutdown>
For protection against heat damage of the ICs, thermal shutdown function monitors chip temperature. The XC9223/9224 series build in three protection
functions: integral latch protection, thermal shutdown, and short-circuit protection. The thermal shutdown circuit starts operating and the driver transistor
O
O
will be turned off when the chip’s temperature reaches 150 C. When the temperature drops to 130 C or less after shutting of the current flow, the IC
performs the soft start function to initiate output startup operation.
<Short-Circuit Protection>
The short-circuit protection circuit monitors FB voltage. In case where output is accidentally shorted to the Ground and when the FB voltage decreases less
than half of the FB voltage, the short-circuit protection operates to turn off the driver transistor. In suspension mode, the operation can be resumed by
either turning the IC off and on via the CE/MODE pin, or by restoring power supply to the VIN pin.
<Voltage Detector>
The detector block of the XC9223/9224 series detects a signal inputted from the VDIN pin by the VDOUT pin.
<U.V.L.O. Circuit>
When the VIN pin voltage becomes 1.4V or lower, the P-channel output driver transistor is forced OFF to prevent false pulse output caused by unstable
operation of the internal circuitry. When the VIN pin voltage becomes 1.8V or higher, switching operation takes place. By releasing the U.V.L.O. function,
the IC performs the soft-start function to initiate output startup operation. The soft-start function operates even when the VIN pin voltage falls momentarily
below the U.V.L.O. operating voltage.
<MODE/SYNC>
A MODE/SYNC pin has two functions, a MODE switch and an input of external clock signal. The MODE/SYNC pin operates as the PWM mode when
applying high level of direct current and the PFM/PWM automatic switching mode by applying low level of direct current, which is the same function as the
normal MODE pin.
internal clock signal.
By applying the external clock signal (±25% of the internal clock signal, ON Duty 25% to 75%), the MODE/SYNC pin switches to the
Also the circuit will synchronize with the falling edge of external clock signal. While synchronizing with the external clock signal, the
MODE/SYNC pin becomes the PWM mode automatically.
If the MODE/SYNC pin holds high or low level of the external clock signal for several µS, the
MODE/SYNC pin stops synchronizing with the external clock and switches to the internal clock operation.
Data Sheet
7
DC000019