LD3870

Preliminary

LINEAR INTEGRATED CIRCUIT

UNISONICTECHNOLOGIESCO.,LTD

5 of 5

www.unisonic.com.tw

QW-R105-028,Da

TYPICAL APPLICATON

For ON/OFF Control is not required:

CONTROL

NOISE

BYPASS

GND

(ceramic or tantalum)

(0~300kΩ)

R

0.1 μF

Cp=0.01 μF

4.7 μF

UTC LD3870

The quiescent current can be reduced by using a resistance “R”. Instead, it increases the minimum operating

voltage. For further information, please refer to Figure ”Output Voltage vs. Control Voltage”.

For In use of ON/OFF CONTROL:

CONTROL

NOISE

BYPASS

GND

(ceramic or tantalum)

R

UTC LD3870

4.7 μF

Cp=0.01 μF

0.1 μF

State of control terminal:

* ”H”

Output is enables.

* ”L”or “open”

Output is disabled.

* Noise bypass Capacitance Cp

-

Noise bypass capacitance Cp reduces noise generated by hand-gap reference circuit.

-

Noise level and ripple rejection will be improved when larger Cp is used.

-

Use of smaller Cp value may cause oscillation.

-

Use the Cp value of 0.01uF greater to avoid the problem.

UTC assumes no responsibility for equipment failures that result from using products at values that

exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or

other parameters) listed in products specifications of any and all UTC products described or contained

herein. UTC products are not designed for use in life support appliances, devices or systems where

malfunction of these products can be reasonably expected to result in personal injury. Reproduction in

whole or in part is prohibited without the prior written consent of the copyright owner. The information

presented in this document does not form part of any quotation or contract, is believed to be accurate

and reliable and may be changed without notice.