XC9248 Datasheet, PDF (1/21 Pages) Torex Semiconductor – 18V Driver Transistor Built-In Synchronous Step-Down DC/DC Converter

XC9248 Series
ETR05022-004
18V Driver Transistor Built-In Synchronous Step-Down DC/DC Converter
˙GENERAL DESCRIPTION
The XC9248 series is 18V bootstrap synchronous step-down DC/DC converter with built-in Nch-Nch driver transistors.
With an input voltage range from 4.5V to 18V and a maximum output current of 2.2A, the series is suitable for digital home
appliance power supplies and can be used with small ceramic capacitors.
The series has a 0.8V reference voltage, and using externally connected resistors, the output voltage can be set freely from
1.0V to 12V.
The control method is synchronous PWM (Source/ Sink). The soft start time is internally set to 2.8ms (TYP.), also can be
adjusted using external capacitor.
With UVLO (Under Voltage Lock Out) function, the internal driver transistors are forced OFF when input voltage falls down
below 3.8V (TYP.).
The series includes over current protection, V_OUT short-circuit protection, Lx short-circuit protection, V_OUT overvoltage
protection and thermal shutdown.
˙APPLICATIONS
˔Digital home appliance
˔Office automation equipment
˔Notebook computers
˔Car accessories power supplies
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˙FEATURES
Input Voltage
Output Voltage
Output Current
Efficiency
Oscillation Frequency
： 4.5V ～ 18V
： 1.0V～12V (V_FB=0.8V±1.5%) ^(*1)
： 2.2A
： 93.8% ^(*1) @VIN=12V,VOUT=5V, IOUT=700mA
： 500kHz
Maximum Duty Cycle
： 79%
Soft-Start Time
： Fixed2.8ms, set by external capacitor
Protection Circuit
： UVLO
High side over current protection
Low side over current protection
V_OUT Short-circuit Protection
L_X Short-circuit Protection
V_OUT Over voltage protection
Thermal shutdown
Package
： SOP-8FD
Environmentally Friendly ： EU RoHS Compliant, Pb Free
(*1) _{Performance depends on external components and wiring on the PCB.}
˙TYPICAL APPLICATION CIRCUIT ˙TYPICAL PERFORMANCE
CHARACTERISTICS
VIN
EN
CIN
CSS
VIN
LX
EN
GND
CBST
SS
BST
FB
VL
CVL
L
CFB
CL
VOUT
RFB1
RFB2
Efficiency vs. Output Current
100
90
80
70
60
50
40
30
20
10
0
0
Ta=25°C
VIN=12V , VOUT=5V
VIN=12V , VOUT=3.3V
500
1000
1500
Output Current : I_OUT [mA]
2000
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