XC9268Series
36V Operation 600mA Synchronous Step-Down DC/DC Converters
ETR05071-001a
■GENERAL DESCRIPTION
The XC9268 series are 36V operation synchronous step-down DC/DC converter ICs with a built-in P-channel MOS driver transistor
and N-channel MOS switching transistor. The XC9268 series has operating voltage range of 3.0V~36.0V and high-efficiency power
supply up to an output current of 600mA. Low ESR capacitors such as ceramic capacitors can be used for the load capacitor (CL).
A 0.75V reference voltage source is incorporated in the IC, and the output voltage can be set to a value from 1.0V to 25.0V using
external resistors (RFB1, RFB2).
1.2MHz or 2.2MHz can be selected for the switching frequency. In automatic PWM/PFM control, the IC operates by PFM control
when the load is light to achieve high efficiency over the full load range from light to heavy.
The soft-start time is internally set to 2.0ms (TYP.), but can be adjusted to set a longer time using an external resistor and capacitor.
With the built-in UVLO function, the driver transistor is forced OFF when input voltage becomes 2.7V or lower.
The output state can be monitored using the power good function.
Internal protection circuits include over current protection and thermal shutdown circuits to enable safe use.
■FEATURES
Input Voltage Range
Output Voltage Range
FB Voltage
■APPLICATIONS
● Electric Meter
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:
3.0 ~ 36V (Absolute Max 40V
1.0 ~ 25V
● Gas Detector
0.75V ± 1.5%
● Various Sensor
Oscillation Frequency
Output Current
1.2MHz, 2.2MHz
● Industrial Equipment
● Home appliance
600mA
Quiescent Current
12.5μA (1.2MHz)
13.5μA (2.2MHz)
Control Methods
PWM/PFM Auto
Efficiency 83%@12V→5V、1mA
Adjustable by RC
Soft-start Time
Protection Circuits
Over Current Protection
Thermal Shutdown
Ceramic Capacitor
- 40℃ ~ + 105℃
Output Capacitor
Operating Ambient Temperature
Packages
SOT-89-5 (Without Power Good)
USP-6C (With Power Good)
EU RoHS Compliant, Pb Free
Environmentally Friendly
■TYPICAL APPLICATION CIRCUIT ■TYPICAL PERFORMANCE
CHARACTERISTICS
L
VIN
Lx
CIN
RFB1
2.2μF
CFB
EN/SS
FB
CL
RFB2
10μF×2
RPG
GND
PG
1/30