XC9235/XC9236/XC9237
Series
■ELECTRICAL CHARACTERISTICS (Continued)
XC9237A18Dxx, VOUT=1.8V, FOSC=3.0MHz, Ta=25℃
PARAMETER
SYMBOL
CONDITIONS
MIN. TYP. MAX. UNIT CIRCUIT
When connected to external components,
VIN=VCE=5.0V, IOUT=30mA
Output Voltage
VOUT
VIN
1.764 1.800 1.836
V
V
①
①
①
Operating Voltage Range
Maximum Output Current
2.0
-
-
6.0
-
VIN=VOUT(E)+2.0V, VCE=1.0V,
IOUTMAX
600
mA
When connected to external components (*9)
VCE=VIN, VOUT=0V,
U.V.L.O. Voltage
VUVLO
1.00 1.40 1.78
V
③
Voltage which Lx pin holding “L” level (*1,*11)
Supply Current
Stand-by Current
IDD
ISTB
VIN=VCE=5.0V, VOUT=VOUT(E)×1.1V
VIN=5.0V, VCE=0V, VOUT=VOUT(E)×1.1V
-
-
21
0
35
1.0
μA
μA
②
②
When connected to external components,
VIN=VOUT(E)+2.0V, VCE=1.0V, IOUT=100mA
Oscillation Frequency
PFM Switching Current
FOSC
2550 3000 3450 kHz
①
①
When connected to external components,
IPFM
170
220
270
mA
VIN=VOUT(E)+2.0V, VCE=VIN, IOUT=1mA (*12)
Maximum IPFM Limit
Maximum Duty Cycle
Minimum Duty Cycle
MAXIPFM
VCE=VIN=(C-1), IOUT=1mA (*12)
-
100
-
200
-
-
300
-
0
%
%
%
①
③
③
MAXDTY VIN=VCE=5.0V, VOUT=VOUT(E)×0.9V
MINDTY
VIN=VCE=5.0V, VOUT=VOUT(E)×0.1V
When connected to external components,
VCE=VIN=VOUT(E)+1.2V, IOUT=100mA
VIN=VCE=5.0V, VOUT =0V, ILx=100mA (*3)
Efficiency
EFFI
-
86
-
%
①
Lx SW "H" ON Resistance 1
Lx SW "H" ON Resistance 2
Lx SW "L" ON Resistance 1
Lx SW "L" ON Resistance 2
Lx SW "H" Leak Current (*5)
Lx SW "L" Leak Current (*5)
Current Limit (*10)
RLxH
RLxH
RLxL
-
-
-
-
-
-
0.35 0.55
0.42 0.67
0.45 0.66
0.52 0.77
Ω
Ω
④
④
-
VIN=VCE=3.6V, VOUT =0V, ILx=100mA (*3)
VIN=VCE=5.0V (*4)
Ω
RLxL
VIN=VCE=3.6V (*4)
Ω
-
ILeakH
ILeakL
ILIM
VIN=VOUT=5.0V, VCE=0V, Lx=0V
VIN=VOUT=5.0V, VCE=0V, Lx=5.0V
VIN=VCE=5.0V, VOUT=VOUT(E)×0.9V (*8)
0.01
0.01
1.0
1.0
μA
μA
mA
⑤
⑤
⑥
900 1050 1350
Output Voltage
Temperature Characteristics VOUT・△topr
△VOUT
IOUT=30mA, -40℃≦Topr≦85℃
-
±100
-
ppm/
℃
①
③
③
VOUT=0V, Applied voltage to VCE
,
CE "H" Voltage
CE "L" Voltage
VCEH
VCEL
0.65
VSS
-
-
VIN
V
Voltage changes Lx to “H” level (*11)
VOUT=0V, Applied voltage to VCE
,
0.25
V
Voltage changes Lx to “L” level (*11)
When connected to external components,
I
OUT=1mA (*6), Voltage which oscillation
VIN -
1.0
PWM "H" Level Voltage
VPWMH
-
-
V
①
frequency becomes 2550kHz≦FOSC≦
3450kHz (*13)
When connected to external components,
IOUT=1mA (*6), Voltage which oscillation
frequency becomes FOSC<2550kHz (*13)
VIN=VCE=5.0V, VOUT=0V
VIN –
0.25
PWM "L" Level Voltage
VPWML
-
-
V
①
CE "H" Current
CE "L" Current
ICEH
ICEL
- 0.1
- 0.1
-
-
0.1
0.1
μA
μA
⑤
⑤
VIN=5.0V, VCE=0V, VOUT=0V
When connected to external components,
VCE=0V → VIN, IOUT=1mA
Soft Start Time
Latch Time
TSS
0.5
1.0
0.9
-
3.0
20
ms
ms
①
⑦
VIN=VCE=5.0V, VOUT=0.8×VOUT(E)
,
TLAT
Short Lx at 1Ω resistance (*7)
Sweeping VOUT, VIN=VCE=5.0V, Short Lx at
1Ω resistance, VOUT voltage which Lx
becomes “L” level within 1ms (*4)
Short Protection
Threshold Voltage
VSHORT
0.675 0.900 1.150
V
⑦
Test conditions: Unless otherwise stated, VIN=5.0V, VOUT(E)=Setting 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 MAXIPFM because those are only for the PFM control’s functions.
*13: XC9235/9236 series exclude VPWMH and VPWML because those are only for the XC9237 series’ functions.
5/28