XCL226 Series

0.5A Inductor Built-in Step-down “micro DC/DC” Converter

The XCL226 series are 18V operation synchronous step-down DC/DC converter ICs with a built-in high-side / low-side driver transistor. The XCL226 series has operating voltage range of 3.0V~18.0V and it can support 0.5A as an output current with high-efficiency. Compatible with Low ESR capacitors such as ceramic capacitors for the load capacitor (CL).

0.75V reference voltage source is incorporated in the IC, and the output voltage can be set to a value from 1.0V to 15.0V using external resistors (RFB1, RFB2). 1.2MHz can be selected for the switching frequency. In PWM/PFM automatic switchover control, IC can change the control method between PWM and PFM based on the output current requirement and as a result IC can achieve high efficiency over the full load range.

XCL226 has a fixed internal soft start time which is 1.0ms (TYP.), additionally the time can be extended by using an external resistor and capacitor.

Typical Application Circuit


Input Voltage 3V~18V(Absolute Max: 20V)
FB Voltage 0.75V±1.5%
Oscillation Frequency 1.2MHz
Output Current 0.5A
Control Methods PWM control (XCL225)
PWM/PFM Automatic (XCL226)
Efficiency 85%@12V→5V、1mA
Soft-start Time Adjustable by RC
Protection Circuits Over Current Protection
Integral Latch Method(XCL225A/XCL226A)
Automatic Recovery(XCL225B/XCL226B)
Thermal Shutdown
Capacitor Low ESR Ceramic Capacitor
Operating Ambient Temperature -40℃~+105℃
Environmentally Friendly EU RoHS Compliant, Pb Free


Package DFN3030-10B Number of Pins 6
Pcs/Reel 3,000 Package Size(mm) 3.0 x 3.0 x 1.7


Technical Document

Quality Reports


QuestionHow does the GO function of DC/DC converters work? Does it work just like a regulator?

Torex regard the PWM/PFM automatic switch control function as Green Operation (GO) in the case of DC/DC. The GO function is defined as the switching operation between the PFM mode for a small output current and the PWM mode for a large output current. The PFM control method controls the output current by increasing and decreasing the fall time according to the output current while keeping a pulse width. The PWM control method controls the output current by adjusting the pulse width of the rise time, which keeps the rise/fall time interval constant and increases the efficiency at a heavy load. By switching between the PFM control for a small output current and the PWM control for a large output current, the quiescent current can be controlled for both of heavy and light loads.

QuestionWhat is the soft-start function?

The function to soften the rise to prevent the inrush current.