NCP612, NCV612

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7

APPLICATIONS INFORMATION

A typical application circuit for the NCP612/NCV612 is

shown in Figure 1, front page.

Input Decoupling (C1)

A 1.0

mF capacitor either ceramic or tantalum is

recommended and should be connected close to the

NCP612/NCV612 package. Higher values and lower ESR

will improve the overall line transient response.

TDK capacitor: C2012X5R1C105K, or C1608X5R1A105K

Output Decoupling (C2)

The NCP612/NCV612 is a stable regulator and does not

require any specific Equivalent Series Resistance (ESR) or

a minimum output current. Capacitors exhibiting ESRs

ranging from a few m

W up to 5.0 W can thus safely be used.

The minimum decoupling value is 1.0

mF and can be

augmented to fulfill stringent load transient requirements.

The regulator accepts ceramic chip capacitors as well as

tantalum capacitors. Larger values improve noise rejection

and load regulation transient response.

TDK capacitor: C2012X5R1C105K, C1608X5R1A105K,

or C3216X7R1C105K

Enable Operation

The enable pin will turn on the regulator when pulled high

and turn off the regulator when pulled low. These limits of

threshold are covered in the electrical specification section

of this data sheet. If the enable is not used then the pin should

Hints

Please be sure the Vin and Gnd lines are sufficiently wide.

When the impedance of these lines is high, there is a chance

to pick up noise or cause the regulator to malfunction.

Set external components, especially the output capacitor,

as close as possible to the circuit, and make leads as short as

possible.

Thermal

As power across the NCP612/NCV612 increases, it might

become necessary to provide some thermal relief. The

maximum power dissipation supported by the device is

dependent upon board design and layout. Mounting pad

configuration on the PCB, the board material and also the

ambient temperature effect the rate of temperature rise for

the part. This is stating that when the NCP612/NCV612 has

good thermal conductivity through the PCB, the junction

temperature will be relatively low with high power

dissipation applications.

The maximum dissipation the package can handle is

given by:

PD +

TJ(max) *TA

RqJA

If junction temperature is not allowed above the

maximum 125C, then the NCP612/NCV612 can dissipate

up to 330 mW @ 25C.

The power dissipated by the NCP612/NCV612 can be

calculated from the following equation:

Ptot + Vin *Ignd (Iout) ) [Vin * Vout] *Iout

or

VinMAX +

Ptot ) Vout * Iout

Ignd ) Iout

If an 100 mA output current is needed then the ground

current from the data sheet is 40

mA. For an

NCP612/NCV612 (3.0 V), the maximum input voltage will

then be 6.0 V (Limited by maximum input voltage).