10/20

XCL219/XCL220 Series

■NOTE ON USE

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. Spike noise and ripple voltage arise in a switching regulator as with a DC/DC converter. These are greatly influenced by

external component selection, such as the coil inductance, capacitance values, and board layout of external components.

Once the design has been completed, verification with actual components should be done.

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.

4. Sufficiently reinforce the ground wiring. In particular, reinforce near the PGND and AGND pin as fluctuations of the ground

phase due to the ground current during switching may cause the operation of the IC to become unstable.

5. Mount external components as close as possible to the IC. Keep the wiring short and thick to lower the wiring impedance.

6. A feature of HiSAT-COT control is that it controls the off time in order to control the duty, which varies due to the effects of

power loss between the input (VIN pin) and output (VOUT pin) due to the load, and thus the switching frequency fluctuates. In

addition, changes in the on time due to 100% duty cycle mode are allowed. For this reason, caution must be exercised as the

characteristics of the switching frequency will vary depending on the external component characteristics, board layout, input

voltage, output voltage, load current and other parameters.

7. Due to propagation delay inside the product, the on time generated by the minimum on time generation circuit may not be the

same as the on time that is the ratio of the input voltage to the output voltage.

8. With regard to the current limiting value, the actual coil current may at times exceed the electrical characteristics due to

propagation delay inside the product.

9. The CE pin is a CMOS input pin. Do not use with the pin open. If connecting to the input or ground, use a resistor up to

1MΩ.

To prevent malfunctioning of the device connected to this product or the input/output due to short circuiting between pins, it is

recommended that a resistor be connected.

10. If the output voltage drops below the short circuit protection threshold voltage at the end of the soft start interval, operation will stop.

11. PWM/PFM auto switching control is a discontinuous conduction mode when the load is light, and in cases where the voltage

difference between input and output is low or the coil inductance is higher than the value indicated in the standard circuit

example, the coil current may reverse when the load is light, and thus pulse skipping will not be possible and light load

efficiency will worsen.