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XCL225/XCL226

Series

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NOTE ON USE(Continued)

1) For the phenomenon of temporal and transitional voltage decrease or voltage increase, the IC may be damaged or

deteriorated if IC is used beyond the absolute MAX. specifications.

2) Make sure that the absolute maximum ratings of the external components and of this IC are not exceeded.

3) The DC/DC converter characteristics depend greatly on the externally connected components as well as on the

characteristics of this IC, so refer to the specifications and standard circuit examples of each component when carefully

considering which components to select. Be especially careful of the capacitor characteristics and use B characteristics

(JIS standard) or X7R, X5R (EIA standard) ceramic capacitors.

The capacitance decrease caused by the bias voltage may become remarkable depending on the external size of the

capacitor.

4) If there is a large dropout voltage, then there might be pulse-skip during light loads even with PWM control.

5) The DC/DC converter of this IC uses a current-limiting circuit to monitor the coil peak current. If the potential dropout voltage

is large or the load current is large, the peak current will increase, which makes it easier for current limitation to be applied which

in turn could cause the operation to become unstable.

6) If there is a large dropout voltage, a circuit delay could create the ramp-up of coil current with staircase waveform exceeding

the current limit.

7) The ripple voltage could be increased when switching from discontinuous conduction mode to Continuous conduction mode.

Please evaluate IC well on customer’s PCB.

8) The operation of becomes unstable below the minimum operating voltage.

9) If the voltage at the EN/SS Pin does not start from 0V but it is at the midpoint potential when the power is switched on, the

soft start function may not work properly and it may cause the larger inrush current and bigger ripple voltages.

10) The effects of ambient noise and the state of the circuit board may cause release from the current limiting state, and

The latch time may lengthen or latch operation may not take place. Please evaluate IC well on customer’s PCB.