US202 Ver la hoja de datos (PDF) - Unisonic Technologies
Número de pieza
componentes Descripción
Fabricante
US202 Datasheet PDF : 5 Pages
| |||
US202/A
CMOS IC
APPLICATION INFORMATION (Cont.)
Reverse Current Preventing
Since the UTC US202/A’s MOSFET is bi-directional, it allows the voltage on VOUT pin is higher than that on VIN
pin. In order to avoid reverse current occur, turn off this switch or connect VIN to a fixed voltage less than 1.2V.
Layout and Thermal Dissipation
The switch should be placed as close to the USB connector as possible and all traces should be as short as
possible to reduce the effect of undesirable parasitic inductance.
Also, place the output capacitor and ferrite beads to the USB connector as close to as possible.
If ferrite beads are used, use wires kept to a minimum resistance and large solder pads to minimize connection
resistance.
If the package is with dual VOUT or VIN pins, short both the same function pins as Fig.1 or Fig.2 to reduce the
internal turn-on resistance. If the output power is delivered to two individual ports, it is specially necessary to short
both VOUT pin at the switch output side in order to protect the switch when each port are plug-in separately.
Under normal operating conditions, the package can dissipate the channel heat away. Wide power bus planes
connected to VIN and VOUT and a ground plane in contact with the device will help dissipate additional heat.
TYPICAL APPLICATION CIRCUIT
VIN
CIN
1µF
VIN
VOUT
EN
VOUT
GND
VOUT
COUT (Note)
470µF
Note: 470µF, Low ESR Electrolytic
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. UTC reserves the right to
make changes to information published in this document, including without limitation specifications and
product descriptions, at any time and without notice. This document supersedes and replaces all
information supplied prior to the publication hereof.
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
5 of 5
QW-R502-445.F
Share Link: 