ZXSC410/ZXSC420/ZXSC440

Document number: DS33618 Rev. 6 - 2

7 of 17

www.diodes.com

August 2015

© Diodes Incorporated

ZXSC410/ZXSC420/ZXSC440

Output Power Calculation

By making the above assumptions for inductance and peak current the output power can be determined by:

x η = (Watts)

Where:









t

t

t

t

x

2

I

I

OFF

ON

DIS

ON

PK

AV







and,

V

L

I

t

IN

PK

ON





and,

V

V

L

I

t

IN

OUT

PK

DIS







and,

≈ 1.7μs (internally set by ZXSC410/420/440)

and,

η = efficiency i.e. 100% = 1

Operating frequency can be derived by:

t

t

1

f

OFF



Output Adjustment

The ZXSC410/420/440 are adjustable output controllers allowing the end user the maximum flexibilty. They can be used both as switching

voltage regulators and as constant current regulators. A feedback voltage of 300mV provides a good compromise for both voltage and current

regulation.

For a constant output voltage operation a potential divider network is connected as follows:

GND

The output voltage is determined by the equation:

















B

A

FB

OUT

R

R

1

V

V

The ZXSC410/420/440 can also be used to generate a constant current between boosted output rail and the VFB pin by connecting a single

resistor between VFB and GND.