AIC1520 Datasheet, PDF (6/7 Pages) Analog Intergrations Corporation – Single High-Side Power Switch

AIC1520
n ^{PIN DESCRIPTION}
PIN 1: IN - Power supply input.
PIN 2: GND - Chip power ground.
PIN 3: OUT - MOSFET switch output.
n ^{APPLICATION INFORMATIONS}
l Current Limit
The current limit threshold is preset internally. It
protects the output MOSFET switches from
damage due to undesirable short circuit conditions
or excess inrush current often encountered during
hot plug-in. AIC1520 allows a minimum current of
0.5A through the MOSFET switches.
USB support dynamic attachment (hot plug-in) of
peripherals. A current surge is caused by the input
capacitance of downstream device. Ferrite beads
are recommended in series with all power and
ground connector pins. Ferrite beads reduce EMI
and limit the inrush current during hot-attachment
by filtering high-frequency signals.
l Thermal Protection
When the chip temperature exceeds 110°C, the
thermal protection function works.
l Supply Filtering
A 0.1mF to 1mF bypass capacitor from IN to GND,
located near the device, is strongly recommended
to control supply transients. Without a bypass
capacitor, an output short may cause sufficient
ringing on the input (from supply lead inductance)
to damage internal control circuitry.
l Transient Droop Requirements
l Short Circuit Transient
Bulk capacitance provides the short-term transient
current needed during a hot-attachment event.
With a 33uF, 16V tantalum or 100uF, 10V
electrolytic capacitor mounted close to
downstream connector should provide transient
drop protection.
l Printed Circuit Layout
The power circuitry of USB printed circuit boards
requires a customized layout to maximize thermal
dissipation and to minimize voltage drop and EMI.
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