1/34
XC9235/XC9236/XC9237
Series
600mA Driver Tr. Built-In, Synchronous Step-Down DC/DC Converters
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100 1000
Output Current:IOUT(mA)
Efficency:EFFI(%
)
PWM/PFM Automatic Sw itching Control
PWM Control
VIN= 4.2V
3.6V
2.4V
VIN= 4.2V
3.6V
2.4V
☆GreenOperation Compatible
■APPLICATIONS
●Mobile phones, Smart phones
●Bluetooth headsets
●Mobile WiMAX PDAs, MIDs, UMPCs
●Portable game consoles
●Digital cameras, Camcorders
●MP3 Players, Portable Media Players
●Notebook computers
ETR0514-013
■FEATURES
Driver Transistor Built-In : 0.42Ω P-ch driver transistor
0.52Ω N-ch switch transistor
Input Voltage : 2.0V ~ 6.0V (A/B/C types)
1.8V ~ 6.0V (D/E/F/G types)
Output Voltage : 0.8V ~ 4.0V (Internally set)
0.9V ~ 6.0V (Externally set)
High Efficiency : 92% (TYP.)*
Output Current : 600mA
Oscillation Frequency : 1.2MHz, 3.0MHz (+15%)
Maximum Duty Cycle : 100%
Control Methods : PWM (XC9235)
PWM/PFM Auto (XC9236)
Function
PWM/PFM Manual (XC9237)
: Current Limiter Circuit Built-In
(Constant Current & Latching)
Capacitor
Operating Ambient Temperature
CL Discharge (B/C/D/E/F/G types)
High Speed Soft Start (B/F/G type)
:
Low ESR Ceramic Capacitor
:-40℃ ~ +85℃
Packages : SOT-25 (A/B/C types only)
USP-6C
USP-6EL(A/B/C types only)
WLP-5-03(A/B types only)
Environmentally Friendly : EU RoHS Compliant, Pb Free
* Performance depends on external components and wiring on the PCB.
■
TYPICAL PERFORMANCE CHARACTERISTICS
●Efficiency vs. Output Current（fOSC=1.2MHz, VOUT=1.8V）
Efficiency: EFFI (%)
●XC9235/XC9236/XC9237
A
/B/C/E/G types (Output Voltage Fixed)
●XC9235/XC9236/XC9237
D/F types (Output Voltage Externally Set)
■
TYPICAL APPLICATION CIRCUIT
■GENERAL DESCRIPTION
The XC9235/XC9236/XC9237 series is a group of synchronous-rectification type DC/DC converters with a built-in 0.42Ω
P-channel MOS driver transistor and 0.52ΩN-channel MOS switching transistor, designed to allow the use of ceramic
capacitors. Operating voltage range is from 2.0V to 6.0V (A～C types), 1.8V to 6.0V (D～G types). For the D/F types which
have a reference voltage of 0.8V (accuracy: ±2.0%), the output voltage can be set from 0.9V by using two external resistors.
The A/B/C/E/G types have a fixed output voltage from 0.8V to 4.0V in increments of 0.05V (accuracy: ±2.0%). The device
provides a high efficiency, stable power supply with an output current of 600mA to be configured using only a coil and two
capacitors connected externally. With the built-in oscillator, either 1.2MHz or 3.0MHz can be selected for suiting to your
particular application. As for operation mode, the XC9235 series is PWM control, the XC9236 series is automatic PWM/PFM
switching control and the XC9237 series can be manually switched between the PWM control mode and the automatic
PWM/PFM switching control mode, allowing fast response, low ripple and high efficiency over the full range of loads (from light
load to heavy load).
The soft start and current control functions are internally optimized. During stand-by, all circuits are shutdown to reduce current
consumption to as low as 1.0μA or less. The B/F/G types have a high speed soft-start as fast as 0.25ms in typical for quick
turn-on. With the built-in UVLO (Under Voltage Lock Out) function, the internal P-channel MOS driver transistor is forced OFF
when input voltage becomes 1.4V or lower.
The B to G types integrate CL discharge function which enables the electric charge at the output capacitor CL to be discharged
via the internal discharge switch located between the LX and VSS pins. When the devices enter stand-by mode, output voltage
quickly returns to the VSS level as a result of this function.
Four types of package SOT-25, USP-6C, USP-6EL and WLP-5-03 are available.
2/34
XC9235
/
XC9236/XC9237
Series
PIN NUMBER
SOT-25 USP-6C/USP-6EL WLP-5-03 PIN NAME FUNCTIONS
1 6 2 VIN Power Input
2 2, 5 3 VSS Ground
3 4 1 CE / MODE High Active Enable / Mode Selection Pin
4 3 4
VOUT
FB
Fixed Output Voltage Pin (A/B/C/E/G types)
Output Voltage Sense Pin (D/F types)
5 1 5 Lx Switching Output
■PIN CONFIGURATION
* Please short the VSS pin (No. 2 and 5).
* The dissipation pad for the USP-6C package should be solder-plated in
recommended mount pattern and metal masking so as to enhance mounting
strength and heat release. If the pad needs to be connected to other pins, it
should be connected to the VSS (No. 5) pin.
■PIN ASSIGNMENT
132
5 4
SOT-25
(Top View)
USP-6C
(BOTTOM VIEW)
VSS CE/MODEVIN
Lx VOUT
CE/MODE 4
2 VSS
VIN 6 1 Lx
3 VOUT (FB)
VSS 5
USP-6EL
(BOTTOM VIEW)
1 Lx
2 VSS
3 VOUT
VIN 6
VSS 5
CE/MODE 4
WLP-5-03
(BOTTOM VIEW)
SOT-25
(TOP VIEW)
3/34
XC9235/XC9236/XC9237
Series
DESIGNATOR ITEM SYMBOL DESCRIPTION
A VIN≧2.0V, No CL discharge, Low speed soft-start
B VIN≧2.0V, CL discharge, High speed soft-start
C VIN≧2.0V, CL discharge, Low speed soft-start
E VIN≧1.8V, CL discharge, Low speed soft-start
Fixed Output voltage (VOUT)
Functional selection
G VIN≧1.8V, CL discharge, High speed soft-start
D VIN≧1.8V, CL discharge, Low speed soft-start
①
Adjustable Output voltage (FB)
Functional selection F VIN≧1.8V, CL discharge, High speed soft-start
Fixed Output Voltage
(VOUT) 08 ~ 40
Output voltage options
e.g. VOUT=2.8V→②=2, ③=8
VOUT=2.85V→②=2, ③=L
0.05V increments: 0.05=A, 0.15=B, 0.25=C, 0.35=D, 0.45=E,
0.55=F, 0.65=H, 0.75=K, 0.85=L, 0.95=M
②③
Adjustable Output Voltage
(FB) 08 Reference voltage is fixed in 0.8V
②=0, ③=8
C 1.2MHz
④ Oscillation Frequency D 3.0MHz
MR SOT-25(*2) (3,000/Reel)
MR-G SOT-25(*2) (3,000/Reel)
ER USP-6C (3,000/Reel)
ER-G USP-6C (3,000/Reel)
4R-G USP-6EL(*2) (3,000/Reel)
⑤⑥-⑦ Packages
(Order Unit)
0R-G WLP-5-03
(*3) (3,000/Reel)
■PRODUCT CLASSIFICATION
●Ordering Information
XC9235①②③④⑤⑥-⑦(*1) Fixed PWM control
XC9236①②③④⑤⑥-⑦(*1) PWM / PFM automatic switching control
XC9237①②③④⑤⑥-⑦(*1) Fixed PWM control QPWM / PFM automatic switching manual selection
(*1) The “-G” suffix denotes Halogen and Antimony free as well as being fully RoHS compliant.
(*2) SOT-25, USP-6EL package are available for the A/B/C series only.
(*3) WLP-5-03 package is available for the A/B series only.
4/34
XC9235
/
XC9236/XC9237
Series
●XC9235 / XC9236 / XC9237
D/F Series
PARAMETER SYMBOL RATINGS UNIT
VIN Pin Voltage VIN - 0.3 ~ 6.5 V
Lx Pin Voltage VLx - 0.3 ~ VIN + 0.3 V
VOUT Pin Voltage VOUT - 0.3 ~ 6.5 V
FB Pin Voltage VFB - 0.3 ~ 6.5 V
CE / MODE Pin Voltage VCE - 0.3 ~ 6.5 V
Lx Pin Current ILx ±1500 mA
SOT-25 250
USP-6C 120
USP-6EL 120
Power Dissipation
WLP-5-03
Pd
750
mW
Operating Ambient Temperature Topr - 40 ~ + 85 OC
Storage Temperature Tstg - 55 ~ + 125 OC
■BLOCK DIAGRAM
NOTE: The signal from CE/MODE Control Logic to PWM/PFM Selector is being fixed to "L" level inside,
and XC9235 series chooses only PWM control.
The signal from CE/MODE Control Logic to PWM/PFM Selector is being fixed to "H" level inside,
and XC9236 series chooses only PWM/PFM automatic switching control.
Diodes inside the circuit are ESD protection diodes and parasitic diodes.
Ta=2 5℃
●XC9235 / XC9236 / XC9237
A Series
●XC9235 / XC9236 / XC9237
B/C/E/G Series
■
A
BSOLUTE MAXIMUM RATINGS
5/34
XC9235/XC9236/XC9237
Series
XC9235A18Cxx/XC9236A18Cxx/XC9237A18Cxx, VOUT=1.8V, fOSC=1.2MHz, Ta=25℃
PARAMETER SYMBOL CONDITIONS MIN. TYP. MAX. UNIT
CIRCUIT
Output Voltage VOUT When connected to external components,
VIN=VCE=5.0V, IOUT=30mA 1.764 1.800 1.836 V ①
Operating Voltage Range VIN 2.0 - 6.0 V ①
Maximum Output Current IOUTMAX VIN=VOUT(E)+2.0V, VCE=1.0V,
When connected to external components (*9) 600 - - mA ①
UVLO Voltage VUVLO VCE =VIN, VOUT=0V,
Voltage which Lx pin holding “L” level (*1, *11) 1.00 1.40 1.78 V ③
Supply Current IDD V
IN=VCE=5.0V, VOUT=VOUT(E)×1.1V - 15 33 μA②
Stand-by Current ISTB V
IN=5.0V, VCE=0V, VOUT=VOUT(E)×1.1V - 0 1.0 μA②
Oscillation Frequency fOSC When connected to external components,
VIN=VOUT(E)+2.0V, VCE =1.0V, IOUT=100mA 1020 1200 1380 kHz ①
PFM Switching Current IPFM When connected to external components,
VIN=VOUT(E)+2.0V, VCE =VIN, IOUT=1mA (*12) 120 160 200 mA ①
PFM Duty Limit DTYLIMIT_PFM V
CE=VIN=(C-1), IOUT=1mA (*12) 200 300 % ①
Maximum Duty Cycle DTYMAX V
IN=VCE=5.0V, VOUT=VOUT(E)×0.9V 100 - - % ③
Minimum Duty Cycle DTYMIN V
IN=VCE=5.0V, VOUT=VOUT(E)×1.1V - - 0 % ③
Efficiency (*2) EFFI
When connected to external components,
VCE=VIN=VOUT(E)+1.2V, IOUT=100mA - 92 - % ①
Lx SW "H" ON Resistance 1 RLxH V
IN=VCE=5.0V, VOUT=0V, ILx=100mA (*3) - 0.35 0.55 Ω ④
Lx SW "H" ON Resistance 2 RLxH V
IN=VCE=3.6V, VOUT=0V, ILx=100mA (*3) - 0.42 0.67 Ω ④
Lx SW "L" ON Resistance 1 RLxL V
IN=VCE=5.0V (*4) - 0.45 0.65 Ω ④
Lx SW "L" ON Resistance 2 RLxL V
IN=VCE=3.6V (*4) - 0.52 0.77 Ω -
Lx SW "H" Leak Current (*5) I
LEAKH V
IN=VOUT=5.0V, VCE=0V, Lx=0V - 0.01 1.0 μA⑤
Lx SW "L" Leak Current (*5) I
LEAKL V
IN=VOUT=5.0V, VCE=0V, Lx=5.0V - 0.01 1.0 μA⑤
Current Limit (*10) I
LIM V
IN=VCE=5.0V, VOUT=VOUT(E)×0.9V (*8) 900 1050 1350 mA ⑥
Output Voltage
Temperature Characteristics
△VOUT/
(VOUT・△Topr)
IOUT=30mA, -40℃≦Topr≦85℃ - ±100 -
ppm/
℃
①
CE "H" Voltage VCEH VOUT=0V, Applied voltage to VCE,
Voltage changes Lx to “H” level (*11) 0.65 - 6.0 V ③
CE "L" Voltage VCEL VOUT=0V, Applied voltage to VCE ,
Voltage changes Lx to “L” level (*11) VSS - 0.25 V ③
PWM "H" Level Voltage VPWMH
When connected to external components,
IOUT=1mA (*6), Voltage which oscillation frequency
becomes 1020 kHz≦fOSC≦1380kHz (*13)
- - VIN - 1.0 V ①
PWM "L" Level Voltage VPWML
When connected to external components,
IOUT=1mA (*6), Voltage which oscillation frequency
becomes fOSC＜1020kHz (*13)
VIN –
0.25 - - V ①
CE "H" Current ICEH V
IN=VCE=5.0V, VOUT=0V - 0.1 - 0.1 μA⑤
CE "L" Current ICEL V
IN=5.0V, VCE=0V, VOUT=0V - 0.1 - 0.1 μA⑤
Soft Start Time tSS When connected to external components,
VCE=0V → V
IN, IOUT=1mA 0.5 1.0 2.5 ms ①
Latch Time tLAT VIN=VCE=5.0V, VOUT=0.8×VOUT(E),
Short Lx at 1Ω resistance
(*7) 1.0 - 20.0 ms ⑦
Short Protection Threshold
Voltage VSHORT
Sweeping VOUT, VIN=VCE=5.0V, Short Lx at
1Ω resistance, VOUT voltage which Lx becomes
“L” level within 1ms
0.675 0.900 1.150 V ⑦
■ELECTRICAL CHARACTERISTICS
Test conditions: Unless otherwise stated, VIN=5.0V, VOUT(E)=Nominal Voltage
NOTE:
*1: Including hysteresis operating voltage range.
*2: EFFI = { ( output voltage×output current ) / ( input voltage×input current) }×100
*3: ON resistance (Ω)= (VIN - Lx pin measurement voltage) / 100mA
*4: R&D value
*5: When temperature is high, a current of approximately 10μA (maximum) may leak.
*6: The CE/MODE pin of the XC9237A series works also as an external switching pin of PWM control and PWM/PFM control. When the IC is in the operation,
control is switched to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3V, and to the PWM
mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0V and equal to or greater than VCEH.
*7: Time until it short-circuits VOUT with GND via 1Ωof resistor from an operational state and is set to Lx=0V from current limit pulse generating.
*8: When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance.
*9: 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.
*10: Current limit denotes the level of detection at peak of coil current.
*11: “H”=VIN~VIN-1.2V, “L”=+0.1V~-0.1V
*12: XC9235 series exclude IPFM and DTYLIMIT_PFM because those are only for the PFM control’s functions.
*13: XC9235/XC9236 series exclude VPWMH and VPW ML because those are onl
y
for the XC9237 series’ functions.
6/34
XC9235
/
XC9236/XC9237
Series
XC9235A18Dxx/XC9236A18Dxx/XC9237A18Dxx, VOUT=1.8V, fOSC=3.0MHz, Ta=25℃
PARAMETER SYMBOL CONDITIONS MIN. TYP. MAX. UNIT
CIRCUIT
Output Voltage VOUT When connected to external components,
VIN=VCE=5.0V, IOUT=30mA 1.764 1.800 1.836 V ①
Operating Voltage Range VIN 2.0 - 6.0 V ①
Maximum Output Current IOUTMAX VIN=VOUT(E)+2.0V, VCE=1.0V,
When connected to external components (*9) 600 - - mA ①
UVLO Voltage VUVLO VCE=VIN, VOUT=0V,
Voltage which Lx pin holding “L” level (*1,*11)
1.00 1.40 1.78 V ③
Supply Current IDD V
IN=VCE=5.0V, VOUT=VOUT(E)×1.1V - 21 35 μA②
Stand-by Current ISTB V
IN=5.0V, VCE=0V, VOUT=VOUT(E)×1.1V - 0 1.0 μA②
Oscillation Frequency fOSC When connected to external components,
VIN=VOUT(E)+2.0V, VCE=1.0V, IOUT=100mA 2550 3000 3450 kHz ①
PFM Switching Current IPFM When connected to external components,
VIN=VOUT(E)+2.0V, VCE=VIN, IOUT=1mA (*12) 170 220 270 mA ①
PFM Duty Limit DTYLIMIT_PFM V
CE=VIN=(C-1), IOUT=1mA (*12) - 200 300 % ①
Maximum Duty Cycle DTYMAX V
IN=VCE=5.0V, VOUT=VOUT(E)×0.9V 100 - - % ③
Minimum Duty Cycle DTYMIN V
IN=VCE=5.0V, VOUT=VOUT(E)×0.1V - - 0 % ③
Efficiency (*2) EFFI
When connected to external components,
VCE=VIN＝VOUT(E)+1.2V, IOUT=100mA - 86 - % ①
Lx SW "H" ON Resistance 1 RLxH V
IN=VCE=5.0V, VOUT =0V, ILx=100mA (*3) - 0.35 0.55 Ω ④
Lx SW "H" ON Resistance 2 RLxH V
IN=VCE=3.6V, VOUT =0V, ILx=100mA (*3) - 0.42 0.67 Ω ④
Lx SW "L" ON Resistance 1 RLxL V
IN=VCE=5.0V (*4) - 0.45 0.65 Ω -
Lx SW "L" ON Resistance 2 RLxL V
IN=VCE=3.6V (*4) - 0.52 0.77 Ω -
Lx SW "H" Leak Current (*5) I
LEAKH V
IN=VOUT=5.0V, VCE=0V, Lx=0V - 0.01 1.0 μA⑤
Lx SW "L" Leak Current (*5) I
LEAKL V
IN=VOUT=5.0V, VCE=0V, Lx=5.0V - 0.01 1.0 μA⑤
Current Limit (*10) I
LIM V
IN=VCE=5.0V, VOUT=VOUT(E)×0.9V (*8) 900 1050 1350 mA ⑥
Output Voltage
Temperature Characteristics
△VOUT/
(VOUT・△Topr)
IOUT=30mA, -40℃≦Topr≦85℃ - ±100 -
ppm/
℃
①
CE "H" Voltage VCEH VOUT=0V, Applied voltage to VCE,
Voltage changes Lx to “H” level (*11) 0.65 - 6.0 V ③
CE "L" Voltage VCEL VOUT=0V, Applied voltage to VCE,
Voltage changes Lx to “L” level (*11) VSS - 0.25 V ③
PWM "H" Level Voltage VPWMH
When connected to external components,
IOUT=1mA (*6), Voltage which oscillation frequency
becomes 2550kHz≦fOSC≦3450kHz (*13)
- - VIN - 1.0 V ①
PWM "L" Level Voltage VPWML
When connected to external components,
IOUT=1mA (*6), Voltage which oscillation frequency
becomes fOSC＜2550kHz (*13)
VIN –
0.25 - - V ①
CE "H" Current ICEH V
IN=VCE=5.0V, VOUT=0V - 0.1 - 0.1 μA⑤
CE "L" Current ICEL V
IN=5.0V, VCE=0V, VOUT=0V - 0.1 - 0.1 μA⑤
Soft Start Time tSS When connected to external components,
VCE=0V → V
IN, IOUT=1mA 0.5 0.9 2.5 ms ①
Latch Time tLAT VIN=VCE=5.0V, VOUT=0.8×VOUT(E),
Short Lx at 1Ω resistance
(*7)
1.0 - 20 ms ⑦
Short Protection Threshold
Voltage VSHORT
Sweeping VOUT, VIN=VCE=5.0V, Short Lx at
1Ω resistance, VOUT voltage which Lx becomes
“L” level within 1ms
0.675 0.900 1.150 V ⑦
■ELECTRICAL CHARACTERISTICS (Continued)
Test conditions: Unless otherwise stated, VIN=5.0V, VOUT(E)=Nominal Voltage
NOTE:
*1: Including hysteresis operating voltage range.
*2: EFFI = { ( output voltage×output current ) / ( input voltage×input current) }×100
*3: ON resistance (Ω)= (VIN - Lx pin measurement voltage) / 100mA
*4: R&D value
*5: When temperature is high, a current of approximately 10μA (maximum) may leak.
*6: The CE/MODE pin of the XC9237A series works also as an external switching pin of PWM control and PWM/PFM control. When the IC is in the operation,
control is switched to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3V, and to the PWM
mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0V and equal to or greater than VCEH.
*7: Time until it short-circuits VOUT with GND via 1Ωof resistor from an operational state and is set to Lx=0V from current limit pulse generating.
*8: When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance.
*9: 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.
*10: Current limit denotes the level of detection at peak of coil current.
*11: “H”=VIN~VIN-1.2V, “L”=+0.1V~-0.1V
*12: XC9235 series exclude IPFM and DTYLIMIT_PFM because those are only for the PFM control’s functions.
*13: XC9235/XC9236 series exclude V
PWMH
and V
PWML
because those are onl
y
for the XC9237 series’ functions.
7/34
XC9235/XC9236/XC9237
Series
XC9235B(C)(E)(G)18Cxx/XC9236B(C)(E)(G)18Cxx/XC9237B(C)(E)(G)18Cxx, VOUT=1.8V, fOSC=1.2MHz, Ta=25℃
PARAMETER SYMBOL CONDITIONS MIN. TYP. MAX. UNIT
CIRCUIT
Output Voltage VOUT When connected to external components,
VIN=VCE=5.0V, IOUT=30mA 1.764 1.800 1.836 V ①
Operating Voltage Range (B/C series)
2.0 - 6.0
Operating Voltage Range (E/G series)
VIN 1.8 - 6.0
V ①
Maximum Output Current IOUTMAX VIN=VOUT(E)+2.0V, VCE=1.0V,
When connected to external components (*9) 600 - - mA ①
UVLO Voltage VUVLO VCE =VIN, VOUT=VOUT(E)×0.5V (*14)
Voltage which Lx pin holding “L” level (*1, *11) 1.00 1.40 1.78 V ③
Supply Current IDD V
IN=VCE=5.0V, VOUT=VOUT(E)×1.1V - 15 33 μA②
Stand-by Current ISTB V
IN=5.0V, VCE=0V, VOUT=VOUT(E)×1.1V - 0 1.0 μA②
Oscillation Frequency fOSC When connected to external components,
VIN=VOUT(E)+2.0V, VCE =1.0V, IOUT=100mA 1020 1200 1380 kHz ①
PFM Switching Current IPFM When connected to external components,
VIN=VOUT(E)+2.0V, VCE =VIN, IOUT=1mA (*12) 120 160 200 mA ①
PFM Duty Limit DTYLIMIT_PFM VCE=VIN=(C-1), IOUT=1mA (*12) 200 300 % ①
Maximum Duty Cycle DTYMAX VIN=VCE=5.0V, VOUT=VOUT(E)×0.9V 100 - - % ③
Minimum Duty Cycle DTYMIN VIN=VCE=5.0V, VOUT=VOUT(E)×1.1V - - 0 % ③
Efficiency (*2) EFFI
When connected to external components,
VCE=VIN=VOUT(E)+1.2V, IOUT=100mA - 92 - % ①
Lx SW "H" ON Resistance 1 RLxH V
IN=VCE=5.0V, VOUT (E)×0.9V , ILx=100mA (*3) - 0.35 0.55 Ω ④
Lx SW "H" ON Resistance 2 RLxH V
IN=VCE=3.6V, VOUT (E)×0.9V , ILx=100mA (*3) - 0.42 0.67 Ω ④
Lx SW "L" ON Resistance 1 RLxL V
IN=VCE=5.0V (*4) - 0.45 0.65 Ω ④
Lx SW "L" ON Resistance 2 RLxL V
IN=VCE=3.6V (*4) - 0.52 0.77 Ω -
Lx SW "H" Leak Current (*5) I
LEAKH V
IN=VOUT=5.0V, VCE=0V, Lx=0V - 0.01 1.0 μA⑤
Current Limit (*10) I
LIM V
IN=VCE=5.0V, VOUT=VOUT(E)×0.9V (*8) 900 1050 1350 mA ⑥
Output Voltage
Temperature Characteristics
△VOUT/
(VOUT・△Topr)
IOUT=30mA, -40℃≦Topr≦85℃ - ±100 -
ppm/
℃
①
CE "H" Voltage VCEH VOUT=
V
OUT(E)×0.9V, Applied voltage to VCE,
Voltage changes Lx to “H” level (*11) 0.65 - 6.0 V ③
CE "L" Voltage VCEL VOUT=
V
OUT(E)×0.9V, Applied voltage to VCE ,
Voltage changes Lx to “L” level (*11) VSS - 0.25 V ③
PWM "H" Level Voltage VPWMH
When connected to external components,
IOUT=1mA (*6), Voltage which oscillation frequency
becomes 1020 kHz≦fOSC≦1380kHz (*13)
- - VIN - 1.0 V ①
PWM "L" Level Voltage VPWML
When connected to external components,
IOUT=1mA (*6), Voltage which oscillation frequency
becomes fOSC＜1020kHz (*13)
VIN –
0.25 - - V ①
CE "H" Current ICEH V
IN=VCE=5.0V,
V
OUT=
V
OUT(E)×0.9V - 0.1 - 0.1 μA⑤
CE "L" Current ICEL V
IN=5.0V, VCE=0V,
V
OUT=
V
OUT(E)×0.9V - 0.1 - 0.1 μA⑤
Soft Start Time (B/G Series) tSS When connected to external components,
VCE=0V → V
IN, IOUT=1mA - 0.25 0.40 ms ①
Soft Start Time (C/E Series) tSS When connected to external components,
VCE=0V → V
IN, IOUT=1mA 0.5 1.0 2.5 ms ①
Latch Time tLAT VIN=VCE=5.0V, VOUT=0.8×VOUT(E),
Short Lx at 1Ω resistance
(*7) 1.0 - 20.0 ms ⑦
Short Protection Threshold
Voltage (B/C Series) VSHORT
Sweeping VOUT, VIN=VCE=5.0V, Short Lx at
1Ω resistance, VOUT voltage which Lx becomes
“L” level within 1ms
0.675 0.900 1.150 V ⑦
Short Protection Threshold
Voltage (E/G Series) VSHORT VIN=VCE=5.0V, The VOUT at Lx=”Low"(*11) while
decreasing VOUT from VOUT (E)×0.4V 0.338 0.450 0.563 V ⑦
CL Discharge RDCHG V
IN=5.0V, LX=5.0V, VCE=0V, VOUT=open 200 300 450 Ω ⑧
■ELECTRICAL CHARACTERISTICS (Continued)
Test conditions: Unless otherwise stated, VIN=5.0V, VOUT(E)=Nominal Voltage, applied voltage sequence is VOUT→VIN→VCE
NOTE:
*1: Including hysteresis operating voltage range.
*2: EFFI = { ( output voltage×output current ) / ( input voltage×input current) }×100
*3: ON resistance (Ω)= (VIN - Lx pin measurement voltage) / 100mA
*4: R&D value
*5: When temperature is high, a current of approximately 10μA (maximum) may leak.
*6: The CE/MODE pin of the XC9237A series works also as an external switching pin of PWM control and PWM/PFM control. When the IC is in the operation,
control is switched to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3V, and to the PWM
mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0V and equal to or greater than VCEH.
*7: Time until it short-circuits VOUT with GND via 1Ωof resistor from an operational state and is set to Lx=0V from current limit pulse generating.
*8: When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance.
*9: 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.
*10: Current limit denotes the level of detection at peak of coil current.
*11: “H”=VIN~VIN-1.2V, “L”=+0.1V~-0.1V
*12: XC9235 series exclude IPFM and DTYLIMIT_PFM because those are only for the PFM control’s functions.
*13: XC9235/XC9236 series exclude VPWMH and VPW ML because those are only for the XC9237 series’ functions.
*14: VIN is applied when VOUT (E) x 0.5V becomes more than VIN.
8/34
XC9235
/
XC9236/XC9237
Series
XC9235B(C)(E)(G)18Dxx/XC9236B(C)(E)(G)18Dxx/XC9237B(C)(E)(G)18Dxx, VOUT=1.8V, fOSC=3.0MHz, Ta=25℃
PARAMETER SYMBOL CONDITIONS MIN. TYP. MAX. UNIT
CIRCUIT
Output Voltage VOUT When connected to external components,
VIN=VCE=5.0V, IOUT=30mA 1.764 1.800 1.836 V ①
Operating Voltage Range (B/C series)
2.0 - 6.0
Operating Voltage Range (E/G series)
VIN 1.8 - 6.0
V ①
Maximum Output Current IOUTMAX VIN=VOUT(E)+2.0V, VCE=1.0V,
When connected to external components (*9) 600 - - mA ①
UVLO Voltage VUVLO VCE=VIN, VOUT=VOUT(E)×0.5V (*14),
Voltage which Lx pin holding “L” level (*1,*11)
1.00 1.40 1.78 V ③
Supply Current IDD V
IN=VCE=5.0V, VOUT=VOUT(E)×1.1V - 21 35 μA②
Stand-by Current ISTB V
IN=5.0V, VCE=0V, VOUT=VOUT(E)×1.1V - 0 1.0 μA②
Oscillation Frequency fOSC When connected to external components,
VIN=VOUT(E)+2.0V, VCE=1.0V, IOUT=100mA 2550 3000 3450 kHz ①
PFM Switching Current IPFM When connected to external components,
VIN=VOUT(E)+2.0V, VCE=VIN, IOUT=1mA (*12) 170 220 270 mA ①
PFM Duty Limit DTYLIMIT_PFM VCE=VIN=(C-1), IOUT=1mA (*12) - 200 300 % ①
Maximum Duty Cycle DTYMAX VIN=VCE=5.0V, VOUT=VOUT(E)×0.9V 100 - - % ③
Minimum Duty Cycle DTYMIN VIN=VCE=5.0V, VOUT=VOUT(E)×0.1V - - 0 % ③
Efficiency(*2) EFFI
When connected to external components,
VCE=VIN＝VOUT(E)+1.2V, IOUT=100mA - 86 - % ①
Lx SW "H" ON Resistance 1 RLxH V
IN=VCE=5.0V, VOUT=
V
OUT(E)×0.9V, ILx=100mA (*3) - 0.35 0.55 Ω ④
Lx SW "H" ON Resistance 2 RLxH V
IN=VCE=3.6V, VOUT=
V
OUT(E)×0.9V, ILx=100mA (*3) - 0.42 0.67 Ω ④
Lx SW "L" ON Resistance 1 RLxL V
IN=VCE=5.0V (*4) - 0.45 0.65 Ω -
Lx SW "L" ON Resistance 2 RLxL V
IN=VCE=3.6V (*4) - 0.52 0.77 Ω -
Lx SW "H" Leak Current (*5) I
LEAKH V
IN=VOUT=5.0V, VCE=0V, Lx=0V - 0.01 1.0 μA⑤
Current Limit (*10) I
LIM V
IN=VCE=5.0V, VOUT=VOUT(E)×0.9V (*8) 900 1050 1350 mA ⑥
Output Voltage
Temperature Characteristics
△VOUT/
(VOUT・△Topr)
IOUT=30mA, -40℃≦Topr≦85℃ - ±100 -
ppm/
℃
①
CE "H" Voltage VCEH
V
OUT=
V
OUT(E)×0.9V, Applied voltage to VCE,
Voltage changes Lx to “H” level (*11) 0.65 - 6.0 V ③
CE "L" Voltage VCEL
V
OUT=
V
OUT(E)×0.9V, Applied voltage to VCE,
Voltage changes Lx to “L” level (*11) VSS - 0.25 V ③
PWM "H" Level Voltage VPWMH
When connected to external components,
IOUT=1mA (*6), Voltage which oscillation frequency
becomes 2550kHz≦fOSC≦3450kHz (*13)
- - VIN - 1.0 V ①
PWM "L" Level Voltage VPWML
When connected to external components,
IOUT=1mA (*6), Voltage which oscillation frequency
becomes fOSC＜2550kHz (*13)
VIN –
0.25 - - V ①
CE "H" Current ICEH V
IN=VCE=5.0V,
V
OUT=
V
OUT(E)×0.9V - 0.1 - 0.1 μA⑤
CE "L" Current ICEL V
IN=5.0V, VCE=0V,
V
OUT=
V
OUT(E)×0.9V - 0.1 - 0.1 μA⑤
Soft Start Time (B/G Series) tSS When connected to external components,
VCE=0V → V
IN, IOUT=1mA - 0.32 0.50 ms ①
Soft Start Time (C/E Series) tSS When connected to external components,
VCE=0V → V
IN, IOUT=1mA 0.5 0.9 2.5 ms ①
Latch Time tLAT VIN=VCE=5.0V, VOUT=0.8×VOUT(E),
Short Lx at 1Ω resistance
(*7) 1.0 - 20 ms ⑦
Short Protection Threshold
Voltage (B/C Series) VSHORT
Sweeping VOUT, VIN=VCE=5.0V, Short Lx at
1Ω resistance, VOUT voltage which Lx becomes
“L” level within 1ms
0.675 0.900 1.150 V ⑦
Short Protection Threshold
Voltage (E/G Series) VSHORT VIN=VCE=5.0V, The VOUT at Lx=”Low"(*11) while
decreasing VOUT from VOUT (E)×0.4V 0.338 0.450 0.563 V ⑦
CL Discharge RDCHG V
IN=5.0V, LX=5.0V, VCE=0V, VOUT=open 200 300 450 Ω ⑧
■ELECTRICAL CHARACTERISTICS (Continued)
Test conditions: Unless otherwise stated, VIN=5.0V, VOUT(E)=Nominal Voltage, applied voltage sequence is VOUT→VIN→VCE
NOTE:
*1: Including hysteresis operating voltage range.
*2: EFFI = { ( output voltage×output current ) / ( input voltage×input current) }×100
*3: ON resistance (Ω)= (VIN - Lx pin measurement voltage) / 100mA
*4: R&D value
*5: When temperature is high, a current of approximately 10μA (maximum) may leak.
*6: The CE/MODE pin of the XC9237A series works also as an external switching pin of PWM control and PWM/PFM control. When the IC is in the operation,
control is switched to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3V, and to the PWM
mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0V and equal to or greater than VCEH.
*7: Time until it short-circuits VOUT with GND via 1Ωof resistor from an operational state and is set to Lx=0V from current limit pulse generating.
*8: When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance.
*9: 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.
*10: Current limit denotes the level of detection at peak of coil current.
*11: “H”=VIN~VIN-1.2V, “L”=+0.1V~-0.1V
*12: XC9235 series exclude IPFM and DTYLIMIT_PFM because those are only for the PFM control’s functions.
*13: XC9235/XC9236 series exclude VPWMH and VPW ML because those are only for the XC9237 series’ functions.
*14: VIN is applied when VOUT (E) x 0.5V becomes more than VIN.
9/34
XC9235/XC9236/XC9237
Series
■ELECTRICAL CHARACTERISTICS (Continued)
XC9235D(F)08Cxx/XC9236D(F)08Cxx/XC9237D(F)08Cxx, FB Type, fOSC=1.2MHz, Ta=25℃
PARAMETER SYMBOL CONDITIONS MIN. TYP. MAX. UNIT
CIRCUIT
FB Voltage VFB VIN = VCE =5.0V, The VFB at Lx=”High"(*11) while
decreasing FB pin voltage from 0.9V. 0.784 0.800 0.816 V ③
Operating Voltage Range VIN 1.8 - 6.0 V ①
Maximum Output Current IOUTMAX VIN=3.2V, VCE=1.0V
When connected to external components (*9) 600 - - mA ①
UVLO Voltage VUVLO VCE
=
VIN
,
VFB
= 0.4V,
Voltage which Lx pin holding “L” level (*1,*11)
1.00 1.40 1.78 V ③
Supply Current IDD V
IN =VCE=5.0V, VFB= 0.88V - 15 μA ②
Stand-by Current ISTB V
IN =5.0V, VCE=0V, VFB= 0.88V - 0 1.0 μA ②
Oscillation Frequency fOSC When connected to external components,
VIN = 3.2V, VCE=1.0V, IOUT=100mA 1020 1200 1380 kHz ①
PFM Switching Current IPFM When connected to external components,
VIN =3.2V, VCE = VIN , IOUT=1mA (*12) 120 160 200 mA ①
PFM Duty Limit DTYLIMIT_PFM VCE= VIN =2.0V IOUT=1mA (*12) 200 300 % ①
Maximum Duty Cycle DTYMAX VIN = VCE =5.0V, VFB = 0.72V 100 - - % ③
Minimum Duty Cycle DTYMIN VIN = VCE =5.0V, VFB = 0.88V - - 0 % ③
Efficiency (*2) EFFI
When connected to external components,
VCE = VIN ＝ 2.4V, IOUT = 100mA - 92 - % ①
Lx SW "H" ON Resistance 1 RLｘH V
IN = VCE = 5.0V, VFB = 0.72V,ILX = 100mA (*3) - 0.35 0.55 Ω ④
Lx SW "H" ON Resistance 2 RLｘH V
IN = VCE = 3.6V, VFB = 0.72V,ILX = 100mA (*3) - 0.42 0.67 Ω ④
Lx SW "L" ON Resistance 1 RLｘL V
IN = VCE = 5.0V (*4) - 0.45 0.65 Ω -
Lx SW "L" ON Resistance 2 RLｘL V
IN = VCE = 3.6V (*4) - 0.52 0.77 Ω -
Lx SW "H" Leak Current (*5) I
LEAKH V
IN = VFB = 5.0V, VCE = 0V, LX= 0V - 0.01 1.0 μA ⑨
Current Limit (*10) I
LIM V
IN = VCE= 5.0V, VFB = 0.72V (*8) 900 1050 1350 mA ⑥
Output Voltage
Temperature Characteristics
△
V
OUT
/
(V
OUT
・△
Topr)
IOUT =30mA
-40℃≦Topr≦85℃ - ±100 - ppm/ ℃ ①
CE "H" Voltage VCEH VFB =0.72V, Applied voltage to VCE,
Voltage changes Lx to “H” level (*11) 0.65 - 6.0 V ③
CE "L" Voltage VCEL VFB =0.72V, Applied voltage to VCE,
Voltage changes Lx to “L” level (*11) VSS - 0.25 V ③
PWM "H" Level Voltage VPWMH
When connected to external components,
IOUT=1mA (*6), Voltage which oscillation frequency
becomes 1020kHz≦fOSC≦1380kHz (*13)
- - VIN - 1.0 V ①
PWM "L" Level Voltage VPW ML
When connected to external components,
IOUT=1mA (*6), Voltage which oscillation frequency
becomes fOSC＜1020kHz (*13)
VIN -
0.25 - - V ①
CE "H" Current ICEH V
IN = VCE =5.0V, VFB =0.72V - 0.1 - 0.1 μA ⑤
CE "L" Current ICEL V
IN =5.0V, VCE = 0V, VFB =0.72V - 0.1 - 0.1 μA ⑤
Soft Start Time (D series) 0.5 1.0 2.5
Soft Start Time (F series) tSS When connected to external components,
VCE = 0V → V
IN , IOUT=1mA - 0.25 0.40
ms ①
Latch Time tLAT VIN=VCE=5.0V, VFB=0.64, Short Lx at 1Ω
resistance (*7) 1.0 - 20.0 ms ⑦
Short Protection Threshold
Voltage VSHORT VIN = VCE =5.0V, The VFB at Lx=”Low" (*11) while
decreasing FB pin voltage from 0.4V. 0.15 0.200 0.25 V ⑦
CL Discharge RDCHG V
IN = 5.0V ,LX = 5.0V, VCE = 0V, VFB= open 200 300 450 Ω ⑧
Test conditions: VOUT=1.2V when the external components are connected. Unless otherwise stated, VIN=5.0V, VOUT(E)=Nominal Voltage, applied voltage sequence is
VOUT→VIN→VCE
NOTE:
*1: Including hysteresis operating voltage range.
*2: EFFI = { ( output voltage×output current ) / ( input voltage×input current) }×100
*3: ON resistance (Ω)= (VIN - Lx pin measurement voltage) / 100mA
*4: R&D value
*5: When temperature is high, a current of approximately 10μA (maximum) may leak.
*6: The CE/MODE pin of the XC9237A series works also as an external switching pin of PWM control and PWM/PFM control. When the IC is in the operation,
control is switched to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3V, and to the PWM
mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0V and equal to or greater than VCEH.
*7: Time until it short-circuits VFB with GND via 1Ωof resistor from an operational state and is set to Lx=0V from current limit pulse generating.
*8: When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance.
*9: 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.
*10: Current limit denotes the level of detection at peak of coil current.
*11: “H”=VIN~VIN-1.2V, “L”=+0.1V~-0.1V
*12: XC9235 series exclude IPFM and DTYLIMIT_PFM because those are only for the PFM control’s functions.
*13: XC9235/XC9236 series exclude VPWMH and VPW ML because those are only for the XC9237 series’ functions.
10/34
XC9235
/
XC9236/XC9237
Series
■ELECTRICAL CHARACTERISTICS (Continued)
XC9235D(F)08Dxx/XC9236D(F)08Dxx/XC9237D(F)08Dxx, FB, fOSC=3.0MHz, Ta=25℃
PARAMETER SYMBOL CONDITIONS MIN. TYP. MAX. UNIT
CIRCUIT
FB Voltage VFB VIN = VCE =5.0V, The VFB at Lx=”High"(*11) while
decreasing FB pin voltage from 0.9V. 0.784 0.800 0.816 V ③
Operating Voltage Range VIN 1.8 - 6.0 V ①
Maximum Output Current IOUTMAX VIN=3.2V, VCE=1.0V
When connected to external components (*9) 600 - - mA ①
UVLO Voltage VUVLO VCE
=
VIN
,
VFB
= 0.4V ,
Voltage which Lx pin holding “L” level (*1, *11)
1.00 1.40 1.78 V ③
Supply Current IDD V
IN =VCE=5.0V, VFB= 0.88V - 21 35 μA ②
Stand-by Current ISTB V
IN =5.0V, VCE=0V, VFB= 0.88V - 0 1.0 μA ②
Oscillation Frequency fOSC When connected to external components,
VIN = 3.2V, VCE=1.0V, IOUT=100mA 2550 3000 3450 kHz ①
PFM Switching Current IPFM When connected to external components,
VIN =3.2V, VCE = VIN , IOUT=1mA (*12) 170 220 270 mA ①
PFM Duty Limit DTYLIMIT_PFM V
CE= VIN =2.2V IOUT=1mA (*12) 200 300 % ①
Maximum Duty Cycle DTYMAX V
IN = VCE =5.0V, VFB = 0.72V 100 - - % ③
Minimum Duty Cycle DTYMIN V
IN = VCE =5.0V, VFB = 0.88V - - 0 % ③
Efficiency (*2) EFFI When connected to external components,
VCE = VIN ＝ 2.4V, IOUT = 100mA - 86 - % ①
Lx SW "H" ON Resistance 1 RLｘH V
IN = VCE = 5.0V, VFB = 0.72V,ILX = 100mA (*3) - 0.35 0.55 Ω ④
Lx SW "H" ON Resistance 2 RLｘH V
IN = VCE = 3.6V, VFB = 0.72V,ILX = 100mA (*3) - 0.42 0.67 Ω ④
Lx SW "L" ON Resistance 1 RLｘL V
IN = VCE = 5.0V (*4) - 0.45 0.65 Ω -
Lx SW "L" ON Resistance 2 RLｘL V
IN = VCE = 3.6V (*4) - 0.52 0.77 Ω -
Lx SW "H" Leak Current (*5) ILEAKH V
IN = VFB = 5.0V, VCE = 0V, LX= 0V - 0.01 1.0 μA ⑨
Current Limit (*10) ILIM V
IN = VCE= 5.0V, VFB = 0.72V (*8) 900 1050 1350 mA ⑥
Output Voltage
Temperature Characteristics
△
V
OUT
/
(V
OUT
・△
Topr)
IOUT =30mA
-40℃≦Topr≦85℃ - ±100 - ppm/ ℃ ①
CE "H" Voltage VCEH VFB =0.72V , VCE,
Voltage changes Lx to “H” level (*11) 0.65 - 6.0 V ③
CE "L" Voltage VCEL VFB =0.72V, VCE,
Voltage changes Lx to “L” level (*11) VSS - 0.25 V ③
PWM "H" Level Voltage VPW MH
When connected to external components,
IOUT = 1mA
(*6)
, Voltage which oscillation frequency
becomes
2550kHz≦fOSC≦3450kHz (*13)
- - VIN - 1.0 V ①
PWM "L" Level Voltage VPWML
When connected to external components,
IOUT = 1mA
(*6)
, Voltage which oscillation frequency
becomes
fOSC＜2550kHz (*13)
VIN -
0.25 - - V ①
CE "H" Current ICEH V
IN = VCE =5.0V, VFB =0.72V - 0.1 - 0.1 μA ⑤
CE "L" Current ICEL V
IN =5.0V, VCE = 0V, VFB =0.72V - 0.1 - 0.1 μA ⑤
Soft Start Time (D series) 0.5 1.0 2.5
Soft Start Time (F series) tSS When connected to external components,
VCE = 0V → V
IN , IOUT=1mA - 0.25 0.40
ms ①
Latch Time tLAT VIN
=
VCE
= 5.0V,
VFB
= 0.64,
Short Lx at 1
Ω
resistance
(*7)
1.0 - 20.0 ms ⑦
Short Protection Threshold
Voltage VSHORT VIN = VCE =5.0V, The VFB at Lx=”Low"
(*11) while
decreasing FB pin voltage from 0.4V.
0.15 0.200 0.25 V ⑦
CL Discharge RDCHG V
IN = 5.0V ,LX = 5.0V ,VCE = 0V ,VFB= open 200 300 450 Ω ⑧
Test conditions: VOUT=1.2V when the external components are connected. Unless otherwise stated, VIN=5.0V, VOUT(E)=Nominal Voltage, applied voltage sequence is
VOUT→VIN→VCE
NOTE:
*1: Including hysteresis operating voltage range.
*2: EFFI = { ( output voltage×output current ) / ( input voltage×input current) }×100
*3: ON resistance (Ω)= (VIN - Lx pin measurement voltage) / 100mA
*4: R&D value
*5: When temperature is high, a current of approximately 10μA (maximum) may leak.
*6: The CE/MODE pin of the XC9237A series works also as an external switching pin of PWM control and PWM/PFM control. When the IC is in the operation,
control is switched to the automatic PWM/PFM switching mode when the CE/MODE pin voltage is equal to or greater than VIN minus 0.3V, and to the PWM
mode when the CE/MODE pin voltage is equal to or lower than VIN minus 1.0V and equal to or greater than VCEH.
*7: Time until it short-circuits VFB with GND via 1Ωof resistor from an operational state and is set to Lx=0V from current limit pulse generating.
*8: When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance.
*9: 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.
*10: Current limit denotes the level of detection at peak of coil current.
*11: “H”=VIN~VIN-1.2V, “L”=+0.1V~-0.1V
*12: XC9235 series exclude IPFM and DTYLIMIT_PFM because those are only for the PFM control’s functions.
*13: XC9235/XC9236 series exclude VPWMH and VPW ML because those are only for the XC9237 series’ functions.
11/34
XC9235/XC9236/XC9237
Series
■ELECTRICAL CHARACTERISTICS (Continued)
(μs)
SERIES fOSC SETTING VOLTAGE MIN. TYP. MAX.
1.2MHz 0.8≦V OUT(E)<1.5 - 250 400
1.2MHz 1.5≦V OUT(E)<1.8 - 320 500
1.2MHz 1.8≦V OUT(E)<2.5 - 250 400
XC9235B(G)/XC9237B(G)
1.2MHz 2.5≦V OUT(E)<4.0 - 320 500
1.2MHz 0.8≦V OUT(E)<2.5 - 250 400
XC9236B(G) 1.2MHz 2.5≦V OUT(E)<4.0 - 320 500
3.0MHz 0.8≦V OUT(E)<1.8 - 250 400
XC9235B(G)/
XC9236B(G)/XC9237B(G) 3.0MHz 1.8≦V OUT(E)<4.0 - 320 500
●PFM Switching Current (IPFM) by Oscillation Frequency and Setting Voltage
●Input Voltage (VIN) for Measuring PFM Duty Limit (DTYLIMIT_PFM)
fOSC 1.2MHz 3.0MHz
C-1 VOUT(E)+0.5V VOUT(E)+1.0V
Minimum operating voltage is 2.0V.
ex.) Although when VOUT(E) is 1.2V and fOSC is 1.2MHz, (C-1) should be 1.7V, (C-1) becomes 2.0V for the minimum operating voltage 2.0V.
(mA)
1.2MHz 3.0MHz
SETTING VOLTAGE MIN. TYP. MAX. MIN. TYP. MAX.
VOUT(E) ≦1.2V 140 180 240 190 260 350
1.2V＜VOUT(E) ≦1.75V 130 170 220 180 240 300
1.8V≦VOUT(E) 120 160 200 170 220 270
●Soft-Start Time, Setting Voltage（XC9235B(G)/XC9236B(G)/XC9237B(G) Series only）
12/34
XC9235
/
XC9236/XC9237
Series
■TYPICAL APPLICATION CIRCUIT
●fOSC=3.0MHz
L: 1.5μH (NR3015, TAIYO YUDEN)
CIN: 4.7μF (Ceramic)
C
L: 10μF (Ceramic)
●fOSC=1.2MHz
L: 4.7μH (NR4018, TAIYO YUDEN)
CIN: 4.7μF (Ceramic)
CL: 10μF (Ceramic)
600mA
Lx
VOUT
V
IN
CE/
MODE
VSS VSS
V
OUT
C
L
(ceramic)
C
IN
(ceramic)
V
IN
CE/MODE
L
●XC9235/XC9236/XC9237A, B, C, E, G Series (Output Voltage Fixed)
●XC9235/XC9236/XC9237D, F Series (Output Voltage External Setting)
<Setting for Output Voltage>
Output voltage can be set externally by adding two resistors to the FB pin. The output voltage is calculated by the RFB1 and
RFB2 value. The total of RFB1 and RFB2 is usually selected less than 1MΩ.
Output voltages can be set in the range of 0.9V to 0.6V by use of 0.8V±2.0% reference voltage. However, when input
voltage (VIN) is lower than the setting output voltage, output voltage (VOUT) can not be higher than the input voltage (VIN).
VOUT=0.8 × (RFB1+RFB2)/RFB2
The value of the phase compensation speed-up capacitor CFB is calculated by the formula of fZFB = 1/(2×π×CFB×RFB1) with
fZFB <10kHz. For optimization, fZFB can be adjusted in the range of 1kHz to 20kHz depending on the inductance L and
the load capacitance CL which are used.
【Formula】
When RFB1=470kΩ and RFB2=150k, VOUT1=0.8 × (470k+150k) / 150k=3.3V
【Example】
VOUT RFB1 RFB2 CFB VOUT RFB1 RFB2 CFB
(V) (kΩ) (kΩ) (pF) (V) (kΩ) (kΩ) (pF)
0.9 100 820 150 2.5 510 240 100
1.2 150 300 100 3.0 330 120 150
1.5 130 150 220 3.3 470 150 100
1.8 300 240 150 4.0 120 30 470
13/34
XC9235/XC9236/XC9237
Series
VIN
VCE
Lx
VOUT
ILx
ILIM
Limit<#ms
Restart
VSS
0mA
Limit>#ms
■OPERATIONAL DESCRIPTION
The XC9235/XC9236/XC9237 series consists of a reference voltage source, ramp wave circuit, error amplifier, PWM
comparator, phase compensation circuit, output voltage adjustment resistors, P-channel MOS driver transistor, N-channel MOS
switching transistor for the synchronous switch, current limiter circuit, UVLO circuit and others. (See the block diagram
above.) The series ICs compare, using the error amplifier, the voltage of the internal voltage reference source with the feedback
voltage from the VOUT pin through split resistors, R1 and R2. 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 1.2MHz or
3.0MHz. Clock pulses generated in this circuit are used to produce ramp waveforms needed for PWM operation, and to
synchronize all the internal circuits.
<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 split resistors, R1 and R2. 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.
<Current Limit>
The current limiter circuit of the XC9235/XC9236/XC9237 series monitors the current flowing through the P-channel MOS
driver transistor connected to the Lx pin, and features a combination of the current limit mode and the operation suspension
mode.
① When the driver current is greater than a specific level, the current limit function operates to turn off the pulses from the Lx
pin at any given timing.
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 a
few ms 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. Once the IC is in suspension mode, operations can be
resumed by either turning the IC off via the CE/MODE pin, or by restoring power to the VIN pin. The suspension mode does
not mean a complete shutdown, but a state in which pulse output is suspended; therefore, the internal circuitry remains in
operation. The current limit of the XC9235/XC9236/XC9237 series can be set at 1050mA at typical. Besides, care must
be taken when laying out the PC Board, in order to prevent misoperation of the current limit mode. Depending on the state
of the PC Board, latch time may become longer and latch operation may not work. In order to avoid the effect of noise, the
board should be laid out so that input capacitors are placed as close to the IC as possible.
14/34
XC9235
/
XC9236/XC9237
Series
■OPERATIONAL DESCRIPTION (Continued)
<Short-Circuit Protection>
The short-circuit protection circuit monitors the internal R1 and R2 divider voltage from the VOUT pin (refer to FB point in
the block diagram shown in the previous page). In case where output is accidentally shorted to the Ground and when
the FB point voltage decreases less than half of the reference voltage (Vref) and a current more than the ILIM flows to
the Pch MOS driver transistor, the short-circuit protection quickly operates to turn off and to latch the driver transistor.
For the D/E/F/G series, it does not matter how much the current limit, once the FB voltage become less than the
quarter of reference voltage (VREF), the short-circuit protection operates to latch the Pch MOS driver transistor. In
latch 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.
When sharp load transient happens, a voltage drop at the VOUT is propagated to the FB point through CFB, as a result,
short circuit protection may operate in the voltage higher than 1/2 VOUT voltage.
<UVLO Circuit>
When the VIN pin voltage becomes 1.4V or lower, the Pch MOS driver transistor 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 UVLO 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 UVLO operating voltage. The UVLO circuit does not cause a complete shutdown of the IC, but causes pulse output to
be suspended; therefore, the internal circuitry remains in operation.
<PFM Switch Current>
In PFM control operation, until coil current reaches to a specified level (IPFM), the IC keeps the Pch MOS driver transistor
on. In this case, time that the Pch MOS driver transistor is kept on (TON) can be given by the following formula.
tON= L
×
IPFM / (VIN
－
VOUT) →IPFM①
< PFM Duty Limit >
In PFM control operation, the PFM duty limit (DTYLIMIT_PFM) is set to 200% (TYP.). Therefore, under the condition that the
duty increases (e.g. the condition that the step-down ratio is small), it’s possible for Pch MOS driver transistor to be turned
off even when coil current doesn’t reach to IPFM. →IPFM②
15/34
XC9235/XC9236/XC9237
Series
Output Voltage Dischage Characteristics
Rdischg （）
= 300Ω TYP
Discharge Time t (ms)
0
10
20
30
40
50
60
70
80
90
100
0 102030405060708090100
CL=10uF
CL=20uF
CL=50uF
■OPERATIONAL DESCRIPTION (Continued)
＜CL High Speed Discharge＞
XC9235B(C)(D)(E)(F)(G)/ XC9236B(C)(D)(E)(F)(G)/ XC9237B(C)(D)(E)(F)(G) series can quickly discharge the electric
charge at the output capacitor (CL) when a low signal to the CE pin which enables a whole IC circuit put into OFF state, is
inputted via the Nch MOS switch transistor located between the LX pin and the VSS pin. When the IC is disabled, electric
charge at the output capacitor (CL) is quickly discharged so that it may avoid application malfunction. Discharge time of the
output capacitor (CL) is set by the CL auto-discharge resistance (R) and the output capacitor (CL). By setting time constant
of a CL auto-discharge resistance value [R] and an output capacitor value (CL) as τ(τ=C x R), discharge time of the
output voltage after discharge via the N channel transistor is calculated by the following formulas.
V = VOUT(E) x e –t/τ or t=τLn (VOUT(E) / V)
V : Output voltage after discharge
VOUT(E) : Output voltage
t: Discharge time
τ: C x R
C= Capacitance of Output capacitor (CL)
R= CL auto-discharge resistance
16/34
XC9235
/
XC9236/XC9237
Series
SW＿CE STATUS
ON Stand-by
OFF Operation
SW＿CE STATUS
ON Operation
OFF Stand-by
SW＿CE SW＿PWM/PFM STATUS
ON * PWM/PFM Automatic Switching Control
OFF ON PWM Control
OFF OFF Stand-by
SW＿CE SW＿PWM/PFM STATUS
ON * Stand-by
OFF ON PWM Control
OFF OFF PWM/PFM Automatic Switching Control
<CE/MODE Pin Function>
The operation of the XC9235/XC9236/XC9237 series will enter into the shut down mode when a low level signal is input to the
CE/MODE pin. During the shutdown mode, the current consumption of the IC becomes 0μA (TYP.), with a state of high
impedance at the Lx pin and VOUT pin. The IC starts its operation by inputting a high level signal to the CE/MODE pin. The
input to the CE/MODE pin is a CMOS input and the sink current is 0μA (TYP.).
●XC9235/XC9236 series - Exam
p
les of how to use CE/MODE
p
in
●XC9237 series - Exam
p
les of how to use CE/MODE
p
in
(A)
(B)
(A)
(B)
Intermediate voltage can be generated by RM1 and RM2. Please set the value of each R1, R2, RM1, RM2 from
few hundreds kΩ to few hundreds MΩ. For switches, CPU open-drain I/O port and transistor can be used.
(A) (B)
(A) (B)
■OPERATIONAL DESCRIPTION (Continued)
17/34
XC9235/XC9236/XC9237
Series
VCEH
VOUT
tSS
0V
0V
90% of setting voltage
OPERATIONAL STATES CE/MODE
VOLTAGE LEVEL XC9235 XC9236 XC9237
H Level (*1) Synchronous
PWM Fixed Control
Synchronous
PWM/PFM
Automatic Switching
Synchronous
PWM/PFM
Automatic Switching
M Level (*2) ━ ━ Synchronous
PWM Fixed Control
L Level (*3) Stand-by Stand-by Stand-by
■FUNCTION CHART
Note on CE/MODE pin voltage level range
(*1) H level: 0.65V < VCE/MODE < 6.0V (for XC9235/XC9236)
H level: VIN – 0.25V < VCE/MODE < VIN (for XC9237)
(*2) M level: 0.65V < VCE/MODE < VIN - 1.0V (for XC9237)
(*3) L level: 0V < VCE/MODE < 0.25V
＜Soft Start＞
Soft start time is available in two options via product selection.
The A,C,D,and E types of XC9235/XC9236/XC9237 se<External Components>
XC9237A18D
■OPERATIONAL DESCRIPTION (Continued)
18/34
XC9235
/
XC9236/XC9237
Series
■NOTE ON USE
1. For temporary, transitional voltage drop or voltage rising phenomenon, the IC is liable to malfunction should the ratings be
exceeded.
2. The XC9235/XC9236/XC9237 series is designed for use with ceramic output capacitors. If, however, the potential
difference is too large between the input voltage and the output voltage, a ceramic capacitor may fail to absorb the resulting
high switching energy and oscillation could occur on the output. If the input-output potential difference is large, connect an
electrolytic capacitor in parallel to compensate for insufficient capacitance.
3. Spike noise and ripple voltage arise in a switching regulator as with a DC/DC converter. These are greatly influenced by
external component selection, such as the coil inductance, capacitance values, and board layout of external components.
Once the design has been completed, verification with actual components should be done.
4. Depending on the input-output voltage differential, or load current, some pulses may be skipped, and the ripple voltage may
increase.
5. When the difference between VIN and VOUT is large in PWM control, very narrow pulses will be outputted, and there is the
possibility that some cycles may be skipped completely.
6. When the difference between VIN and VOUT is small, and the load current is heavy, very wide pulses will be outputted and
there is the possibility that some cycles may be skipped completely.
7. With the IC, the peak current of the coil is controlled by the current limit circuit. Since the peak current increases when
dropout voltage or load current is high, current limit starts operation, and this can lead to instability. When peak current
becomes high, please adjust the coil inductance value and fully check the circuit operation. In addition, please calculate
the peak current according to the following formula:
Ipk = (VIN - VOUT) x OnDuty / (2 x L x fOSC) + IOUT
L: Coil Inductance Value
fOSC: Oscillation Frequency
8. When the peak current which exceeds limit current flows within the specified time, the built-in Pch MOS driver transistor
turns off. During the time until it detects limit current and before the built-in transistor can be turned off, the current for limit
current flows; therefore, care must be taken when selecting the rating for the external components such as a coil.
9. When VIN is less than 2.4V, limit current may not be reached because voltage falls caused by ON resistance.
10. Care must be taken when laying out the PC Board, in order to prevent misoperation of the current limit mode. Depending
on the state of the PC Board, latch time may become longer and latch operation may not work. In order to avoid the effect of
noise, the board should be laid out so that input capacitors are placed as close to the IC as possible.
11. Use of the IC at voltages below the recommended voltage range may lead to instability.
12. This IC should be used within the stated absolute maximum ratings in order to prevent damage to the device.
13. When the IC is used in high temperature, output voltage may increase up to input voltage level at no load because of the
leak current of the driver transistor.
14. The current limit is set to 1350mA (MAX.) at typical. However, the current of 1350mA or more may flow. In case that the
current limit functions while the VOUT pin is shorted to the GND pin, when Pch MOS driver transistor is ON, the potential
difference for input voltage will occur at both ends of a coil. For this, the time rate of coil current becomes large. By
contrast, when Nch MOS driver transistor is ON, there is almost no potential difference at both ends of the coil since the
VOUT pin is shorted to the GND pin. Consequently, the time rate of coil current becomes quite small. According to the
repetition of this operation, and the delay time of the circuit, coil current will be converged on a certain current value,
exceeding the amount of current, which is supposed to be limited originally. Even in this case, however, after the over
current state continues for several ms, the circuit will be latched. A coil should be used within the stated absolute
maximum rating in order to prevent damage to the device.
①Current flows into Pch MOS driver transistor to reach the current limit (ILIM).
②The current of ILIM or more flows since the delay time of the circuit occurs during from the detection of the current limit to
OFF of Pch MOS driver transistor.
③Because of no potential difference at both ends of the coil, the time rate of coil current becomes quite small.
④Lx oscillates very narrow pulses by the current limit for several ms.
⑤The circuit is latched, stopping its operation.
19/34
XC9235/XC9236/XC9237
Series
●The Range of L Value
fOSC VOUT L Value
3.0MHz 0.8V＜VOUT<4.0V 1.0μH～2.2μH
VOUT≦2.5V 3.3μH～6.8μH
1.2MHz 2.5V＜VOUT 4.7μH～6.8μH
*When a coil less value of 4.7μH is used at
fOSC=1.2MHz or when a coil less value of 1.5μH is
used at fOSC=3.0MHz, peak coil current more easily
reach the current limit ILMI. In this case, it may
happen that the IC can not provide 600mA output
current.
■NOTE ON USE (Continued)
15. In order to stabilize VIN’s voltage level and oscillation frequency, we recommend that a by-pass capacitor (CIN) be
connected as close as possible to the VIN & VSS pins.
16. High step-down ratio and very light load may lead an intermittent oscillation.
17. During PWM / PFM automatic switching mode, operating may become unstable at transition to continuous mode.
Please verif
y
with actual
p
arts.
18. Please note the inductance value of the coil. The IC may enter unstable operation if the combination of ambient
temperature, setting voltage, oscillation frequency, and L value are not adequate.
In the operation range close to the maximum duty cycle, The IC may happen to enter unstable output voltage operation
even if using the L values listed below.
<External Components>
19. It may happen to enter unstable operation when the IC goes into continuous operation mode under the condition of large
input-output voltage difference. Care must be taken with the actual design unit.
<External Com
p
onents>
20. Torex places an importance on improving our products and their reliability.
We request that users incorporate fail-safe designs and post-aging protection treatment when using Torex products in their
systems.
20/34
XC9235
/
XC9236/XC9237
Series
21. Instructions of pattern layouts
(1) In order to stabilize VIN voltage level, we recommend that a by-pass capacitor (CIN) be connected as close as possible to
the VIN & VSS pins.
(2) Please mount each external component as close to the IC as possible.
(3) Wire external components as close to the IC as possible and use thick, short connecting traces to reduce the circuit
impedance.
(4) Make sure that the PCB GND traces are as thick as possible, as variations in ground potential caused by high ground
currents at the time of switching may result in instability of the IC.
(5) This series’ internal driver transistors bring on heat because of the output current and ON resistance of driver transistors.
■NOTE ON USE (Continued)
22. NOTE ON MOUNTING (WLP-5-03)
(1) Mount pad design should be optimized for user's conditions.
(2) Sn-AG-Cu is used for the package terminals. If eutectic solder is used, mounting reliability is decreased. Please do not
use eutectic solder paste.
(3) When underfill agent is used to increase interfacial bonding strength, please take enough evaluation for selection. Some
underfill materials and applied conditions may decrease bonding reliability.
(4) The IC has exposed surface of silicon material in the top marking face and sides so that it is weak against mechanical
damages. Please take care of handling to avoid cracks and breaks.
(5) The IC has exposed surface of silicon material in the top marking face and sides. Please use the IC with keeping the
circuit open (avoiding short-circuit from the out).
(6) Semi-transparent resin is coated on the circuit face of the package. Please be noted that the usage under strong lights
may affects device performance.
21/34
XC9235/XC9236/XC9237
Series
< Circuit No.9 >
VIN Lx
VSS
CE/MODE VOUT
(FB)
A
CIN
< Circuit No.8 > ILx
VIN Lx
VSS
CE/MODE VOUT
(FB)
1uF
A
< Circuit No.1 >
※ External Components
L : 1.5uH(NR3015) 3.0MHz
4.7uH(NR4018) 1.2MHz
CIN : 4.7μF(ceramic)
CL :10μF(ceramic)
< Circuit No.2 >
VIN Lx
VSS
CE/MODE VOUT
A
VRL
CL
L
CIN
Wave Form Measure Point
< Circuit No.3 >
< Circuit No.4 >
VIN Lx
VSS
CE/MODE VOUT
(FB)
A
1uF
ON resistance = (VIN-VLx)/100mA
VIN Lx
VSS
CE/MODE VOUT
(FB)
1uF V100mA
VIN Lx
VSS
CE/MODE VOUT
(FB)
1uF
Rpulldown
200Ω
Wave Form Measure Point
< Circuit No.7 >
VIN Lx
VSS
CE/MODE VOUT
(FB)
1uF
Rpulldown
1Ω
Ilat
Wave Form Measure Point
< Circuit No.6 >
VIN Lx
VSS
CE/MODE VOUT
(FB)
1uF VILIM
Wave Form Measure Point
< Circuit No.5 >
A
ICEH
ICEL
VIN Lx
VSS
CE/MODE VOUT
(FB)
1uF A
VIN Lx
VSS
CE/MODE FB
CIN
V
IOUT
CL
L
Wave Form Measure Point
※ External Components
L : 1.5μH(NR4018) 3.0MHz VOUT=VFB×(R1+R2)/R2
: 4.7μH (NR3015) 1.2MHz
CIN : 4.7μF
CL : 10μF
R1 : 150kΩ
R2 : 300kΩ
Cfb : 120pF
R1
R2
Cfb
A
RL
・A/B/C/E/G series ・D/F series
■TEST CIRCUITS
22/34
XC9235
/
XC9236/XC9237
Series
(1) Efficiency vs. Output Current
(2) Output Voltage vs. Output Current
(3) Ripple Voltage vs. Output Current
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100 1000
Output Current:IOUT(mA)
Efficency:EFFI(%
)
PWM/PFM A u tomatic Sw it c hing Contr ol
PWM Control
VIN= 4.2V
3.6V
2.4V
VIN= 4.2V
3.6V
2.4V
0
10
20
30
40
50
60
70
80
90
100
0.1 1 10 100 1000
Output Current:IOUT(mA)
Efficency:EFFI(%
)
PWM/PFM A u tomatic Sw it c hing Contr ol
PWM Control
VIN= 4.2V
3.6V
2.4V
VIN= 4.2V
3.6V
2.4V
1.5
1.6
1.7
1.8
1.9
2.0
2.1
0.1 1 10 100 1000
Output Current:IOUT(mA)
Output Voltage:Vout(V)
PWM/PFM A ut omatic Sw it c hing Cont r ol
VIN
＝4.2V,3.6V,2.4V
PWM Co n tr o l
1.5
1.6
1.7
1.8
1.9
2.0
2.1
0.1 1 10 100 1000
Output Current:IOUT(mA)
Output Voltage:Vout(V)
PWM/PFM Automatic Sw itching Control
VIN
＝4.2V,3.6V,2.4V
PWM Control
0
20
40
60
80
100
0.1 1 10 100 1000
Output Current:IOUT(mA)
Ripple Voltage:Vr(mV)
PWM Control
VIN
＝4.2V,3.6V,2.4V
PWM/ PFM A u t omat ic
Sw itching Control
VIN
＝4.2V
3.6V
2.4V
0
20
40
60
80
100
0.1 1 10 100 1000
Output Current:IOUT(mA)
Ripple Voltage:Vr(mV)
PWM/PFM Automatic
Sw itching Control
VIN
＝4.2V
3.6V
2.4V
PWM Control
VIN
＝4.2V,3.6V,2.4V
■TYPICAL PERFORMANCE CHARACTERISTICS
Output Current: IOUT (mA) Output Current: IOUT (mA)
Efficiency: EFFI (%)
Efficiency: EFFI (%)
XC9237A18C
L=4.7
μ
H
(
NR40Ambient Tem
p
erature: Ta
(
℃
)
XC9237A18D
L=1.5μH (NR3015), CIN=4.7μF, CL=10μF
Output Current: IOUT (mA) Output Current: IOUT (mA)
Output Voltage: VOUT (V)
XC923 ●Soft-Start Time, Setting XC9237A18D
L=1.5μH (NR3015), CIN=4.7μF, CL=10μF
XC9237A18C
L=4.7μH (NR4018), CIN=4.7μF, CL=10μF
XC9237A18D
L=1.5μH (NR3015), CIN=4.7μF, CL=10μF
Output Current: IOUT (mA)
Ripple Voltage: Vr (mV)
Output Current: IOUT Supply
23/34
XC9235/XC9236/XC9237
Series
(4) Oscillation Frequency vs. Ambient Temperature
(5) Supply Current vs. Ambient Temperature
(6) Output Voltage vs. Ambient Temperature (7) UVLO Voltage vs. Ambient Temperature
1.5
1.6
1.7
1.8
1.9
2.0
2.1
-50-250 255075100
Ambient Temperature: Ta (℃)
Output Voltage : VOUT (V)
VIN=3.6V
0.0
0.3
0.6
0.9
1.2
1.5
1.8
-50-250 255075100
Ambient Temperature: Ta (℃)
UVLO Voltage : UVLO (V)
CE=V IN
0
5
10
15
20
25
30
35
40
-50 -25 0 25 50 75 100
Ambient Temperature: Ta (℃)
Supply Current : IDD (μA
)
VIN=6.0V
VIN=4.0V
VIN=2.0V
0
5
10
15
20
25
30
35
40
-50-250 255075100
Ambient Temperature: Ta (℃)
Supply Current : IDD (μA
)
VIN=6.0V
VIN=4.0V
VIN=2.0V
0.8
0.9
1.0
1.1
1.2
1.3
1.4
1.5
-50 -25 0 25 50 75 100
Ambient Temperature: Ta (℃)
VIN=3.6V
Oscillation Frequency : FOSC(MHz)
2.5
2.6
2.7
2.8
2.9
3.0
3.1
3.2
3.3
3.4
3.5
-50 -25 0 25 50 75 100
Ambient Temperature: Ta (℃)
VIN=3.6V
Oscillation Frequency : FOSC(MHz)
■TYPICAL PERFORMANCE CHARACTERISTICS (Continued)
Ambient Temperature: Ta (℃)
Oscillation Frequency: FOSC (MHz)
Ambient Temperature: Ta (℃)
Oscillation Frequency: FOSC (MHz)
Supply Current: IDD (μA)
Supply Current: IDD (μA)
Ambient Temperature: Ta (℃) Ambient Temperature: Ta (℃)
Ambient Temperature: Ta (℃) Ambient Temperature: Ta (℃)
UVLO Voltage: UVLO (V)
XC9237A18C
L=4.7μH (NR4018), CIN=4.7μF, CL=10μF
XC9237A18D
L=1.5μH (NR3015), CIN=4.7μF, CL=10μF
XC9237A18C XC9237A18D
XC9237A18D XC9237A18D
Output Voltage: VOUT (V)
24/34
XC9235
/
XC9236/XC9237
Series
(8) CE "H" Voltage vs. Ambient Temperature (9) CE "L" Voltage vs. Ambient Temperature
(10) Soft Start Time vs. Ambient Temperature
(11) "Pch / Nch" Driver on Resistance vs. Input Voltage
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0123456
Input Voltage : VIN (V)
Pch on Resistance
Nch on Resistance
Lx SW ON Resistance:RLxH,RLxL (Ω)
0
1
2
3
4
5
-50 -25 0 25 50 75 100
Ambient Temperature: Ta (℃)
Soft Start Time : TSS (ms
)
VIN=3.6V
0
1
2
3
4
5
-50-25 0 255075100
Ambient Temperature: Ta (℃)
Soft Start Time : TSS (ms
)
VIN=3.6V
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
-50 -25 0 25 50 75 100
Ambient Temperature: Ta (℃)
CE "H" Voltage : VCEH (V
)
VIN=5.0V
VIN=3.6V
VIN=2.4V
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
-50 -25 0 25 50 75 100
Ambient Temperature: Ta (℃)
CE "L" Voltage : VCEL (V)
VIN=5.0V
VIN=3.6V
VIN=2.4V
■TYPICAL PERFORMANCE CHARACTERISTICS (Continued)
A
mbient TempOutput Current: IOUT (mA)
CE “H” Voltage: VCEH (V)
CE “L” Voltage: VCEL (V)
Input Voltage: VIN (V)<External Components>
Lx SW ON Resistance: RLxH, RLxL (Ω)
A
mbiRipple Voltage: Vr (mV)
Soft Start Time: TSS (ms)
Soft Start Time: TSS (ms)
XC9237A18C
L=4.7μH (NR4018), CIN=4.7μF, CL=10μF
XC9237A18D
L=1.5μH (NR3015), CIN=4.7μF, CL=10μF
Ambient Temperature: Ta (℃)
Ambient Temperature: Ta (℃)
XC9237A18D XC9237A18D
XC9237A18D
25/34
XC9235/XC9236/XC9237
Series
(12) XC9235B/36B/37B Rise Wave Form
(13) XC9235B/36B/37B Soft-Start Time vs. Ambient Temperature
XC9237B12C XC9237B33D
L=4.7μH(NR4018), CIN=4.7μF, C L = 1 0 μF L=1.5μH(NR3015), CIN=4.7μF, C L = 1 0 μF
(14) XC9235B/36B/37B CL Discharge Resistance vs. Ambient Temperature
XC9237B33D
100
200
300
400
500
600
-50 -25 0 25 50 75 100
Ambient Temperature: Ta (℃)
VIN=6.0V
VIN=4.0V
VIN=2.0V
0
100
200
300
400
500
-50 -25 0 25 50 75 100
Ambient Temperature: Ta(℃)
Soft Start Time :TSS (μs)
0
100
200
300
400
500
-50 -25 0 25 50 75 100
Ambient Temperature: Ta(℃)
Soft Start Time :TSS (μs)
VIN=5.0V
IOUT=1.0mA
VIN=5.0V
IOUT=1.0mA
XC9237B12C
L=4.7μH (NR4018), CIN=4.7μF, CL=10μF
XC9237B33D
L=1.5μH (NR3015), CIN=4.7μF, CL=10μF
100μs/div 100μs/div
CL Discharge Resistance: (Ω)
VIN=5.0V
IOUT=1.0m
A
VIN=5.0V
IOUT=1.0m
A
VOUT：0.5V/div VOUT：1.0V/div
CE：0.0V⇒1.0V CE：0.0V⇒1.0V
■TYPICAL PERFORMANCE CHARACTERISTICS (Continued)
26/34
XC9235
/
XC9236/XC9237
Series
(15) Load Transient Response
XC9237A18C
L=4.7μH (NR4018), CIN=4.7μF (ceramic), CL=10μF (ceramic), Topr=25℃
VIN=3.6V, VCE=VIN (PWM/PFM Automatic Switching Control)
IOUT=1mA → 100mA IOUT=1mA → 300mA
1ch: IOUT 1ch: I
OUT
2ch 2ch
VOUT: 50mV/div V
OUT: 50mV/div
50μs/div 50μs/div
IOUT=100mA → 1mA I
OUT=300mA → 1mA
1ch: IOUT 1ch: I
OUT
2ch 2ch
VOUT: 50mV/div V
OUT: 50mV/div
200μs/div 200μs/div
■TYPICAL PERFORMANCE CHARACTERISTICS (Continued)
27/34
XC9235/XC9236/XC9237
Series
(15) Load Transient Response (Continued)
XC9237A18C
L=4.7μH (NR4018), CIN=4.7μF (ceramic), CL=10μF (ceramic), Topr=25℃
VIN=3.6V, VCE=1.8V (PWM Control)
IOUT=1mA → 100mA IOUT=1mA → 300mA
1ch: IOUT 1ch: I
OUT
2ch 2ch
VOUT: 50mV/div V
OUT: 50mV/div
50μs/div 50μs/div
IOUT=100mA → 1mA I
OUT=300mA → 1mA
1ch: IOUT 1ch: I
OUT
2ch 2ch
VOUT: 50mV/div V
OUT: 50mV/div
200μs/div 200μs/div
■TYPICAL PERFORMANCE CHARACTERISTICS (Continued)
28/34
XC9235
/
XC9236/XC9237
Series
(15) Load Transient Response (Continued)
XC9237A18D
L=1.5μH (NR3015), CIN=4.7μF (ceramic), CL=10μF (ceramic), Topr=25℃
VIN=3.6V, VCE=VIN (PWM/PFM Automatic Switching Control)
IOUT=1mA → 100mA IOUT=1mA → 300mA
1ch: IOUT 1ch: I
OUT
2ch 2ch
VOUT: 50mV/div V
OUT: 50mV/div
50μs/div 50μs/div
IOUT=100mA → 1mA I
OUT=300mA → 1mA
1ch: IOUT 1ch: I
OUT
2ch 2ch
VOUT: 50mV/div V
OUT: 50mV/div
200μs/div 200μs/div
■TYPICAL PERFORMANCE CHARACTERISTICS (Continued)
29/34
XC9235/XC9236/XC9237
Series
(15) Load Transient Response (Continued)
XC9237A18D
L=1.5μH (NR3015), CIN=4.7μF (ceramic), CL=10μF (ceramic), Topr=25℃
VIN=3.6V, VCE=1.8V (PWM Control)
IOUT=1mA → 100mA IOUT=1mA → 300mA
1ch: IOUT 1ch: I
OUT
2ch 2ch
VOUT: 50mV/div V
OUT: 50mV/div
50μs/div 50μs/div
IOUT=100mA → 1mA IOUT=300mA → 1mA
1ch: IOUT 1ch: I
OUT
2ch 2ch
VOUT: 50mV/div V
OUT: 50mV/div
200μs/div 200μs/div
■TYPICAL PERFORMANCE CHARACTERISTICS (Continued)
30/34
XC9235
/
XC9236/XC9237
Series
■PACKAGING INFORMATION
●SOT-25 ●USP-6C
●USP-6C Reference Pattern Layout ●USP-6C Reference Metal Mask Design
2.4
2
34
5
6
1
0.45
1.0
0.05
0.05
0.45
31/34
XC9235/XC9236/XC9237
Series
●USP-6EL
■PACKAGING INFORMATION (Continued)
0.35
1.5
0.3750.375
0.55 0.55
1.1
2.25
0.30.3
0.9
2.2
0.5
0.3
1.4
0.55 0.55
* A part of the pin may appear from the side of the package because of it’s
structure, but reliability of the package and strength will not be changed below the
standard.
●USP-6EL Reference Pattern Layout ●USP-6EL Reference Metal Mask Design
32/34
XC9235
/
XC9236/XC9237
Series
●WLP-5-03
■PACKAGING INFORMATION (Continued)
3
1
2
4
5
1.06±0.04
(0.3)
(0.5)
1pin INDENT
33/34
XC9235/XC9236/XC9237
Series
① represent product series
PRODUCT
SERIES XC9235 XC9236 XC9237
A 4 5 6
B C D E
C K L M
D K L M
E 4 5 6
F 2 7 B
G C D E
② represents integer number of output voltage and oscillation frequency
●A/B/C/F Series
MARK OUTPUT
VOLTAGE (V) fOSC=1.2MHz fOSC=3.0MHz
0.X A F
1.X B H
2.X C K
3.X D L
4.X E M
●E/G/D Series
MARK
OUTPUT
VOLTAGE (V) fOSC=1.2MlHz fOSC=3.0MlHz
0.X N U
1.X P V
2.X R X
3.X S Y
4.X T Z
③ represents decimal point of output voltage
VOUT (V) MARK VOUT (V) MARK
X.00 0 X.05 A
X.10 1 X.15 B
X.20 2 X.25 C
X.30 3 X.35 D
X.40 4 X.45 E
X.50 5 X.55 F
X.60 6 X.65 H
X.70 7 X.75 K
X.80 8 X.85 L
X.90 9 X.95 M
④⑤ represents production lot number
Order of 01～09, 0A～0Z, 11～9Z, A1～A9, AA～AZ, B1～ZZ.
(G, I, J, O, Q, W excluded)
*No character inversion used.
■MARKING RULE
●SOT-25
SOT-25
(TOP VIEW)
USP-6C/USP-6EL
(TOP VIEW)
●USP-6C/USP-6EL
●WLP-5-03
12
43
③① ②
④ ⑤
5
WLP-5-03
(TOP VIEW)
34/34
XC9235
/
XC9236/XC9237
Series
1. The products and product specifications contained herein are subject to change without
notice to improve performance characteristics. Consult us, or our representatives
before use, to confirm that the information in this datasheet is up to date.
2. We assume no responsibility for any infringement of patents, patent rights, or other
rights arising from the use of any information and circuitry in this datasheet.
3. Please ensure suitable shipping controls (including fail-safe designs and aging
protection) are in force for equipment employing products listed in this datasheet.
4. The products in this datasheet are not developed, designed, or approved for use with
such equipment whose failure of malfunction can be reasonably expected to directly
endanger the life of, or cause significant injury to, the user.
(e.g. Atomic energy; aerospace; transport; combustion and associated safety
equipment thereof.)
5. Please use the products listed in this datasheet within the specified ranges.
Should you wish to use the products under conditions exceeding the specifications,
please consult us or our representatives.
6. We assume no responsibility for damage or loss due to abnormal use.
7. All rights reserved. No part of this datasheet may be copied or reproduced without the
prior permission of TOREX SEMICONDUCTOR LTD.
