AIC1531 ETC2 [List of Unclassifed Manufacturers], AIC1531 Datasheet - Page 7

• Manufacturer Part Number: AIC1531
• Description: 500mA Dual Linear Regulator with Internal Power Switch
• Manufacturer: ETC2 [List of Unclassifed Manufacturers]

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BLOCK DIAGRAM
PIN DESCRIPTION
PIN 1: VSBY - Standby supply voltage (5V) input
PIN 2: VCC
PIN 3: VOUT - 3.3V regulated output
APPLICATIONS INFORMATION
The Requirement for External Capacitors
The selection of the output capacitor is based on
two requirements: LDO compensation and the
transition between power sources. During the
takeover between sources, the output capacitor
provides the loading. Therefore a larger output
capacitor can improve the transition. And since the
output capacitor plays the important role in the
compensation of LDO, a 10 F Tantalum capacitor
or larger is recommended.
The input capacitor is required to be as close to the
- Primary supply voltage (5V) input
for 3.3V regulator when VCC falls
below V
operate in “ Wake-On-LAN” mode
get a 5V standby through a cable
that connects directly to a specific
header on the Motherboard.
for 3.3V regulator.
when either V
CCDES
CC
. Some NICs that
or V
SBY
is present.
voltage
PIN 4: AUX
PIN 5-8: GND
IC as possible. The input capacitor can reduce the
parasitic effect formed by the power supply output
impedance or the trace. A 10 F Tantalum capacitor
is a good choice. Additional ceramic capacitor can
be placed close to input and output to reduce the
high frequency noise. A 0.1 F is recommended.
The layout and Thermal Considerations
The AIC1531 is housed in a thermally enhanced
package where the GND pins (Pin5 to Pin8) are
integrated to the leadframe. Generally, heat sinks
are not available for most surface-mounted devices.
- Auxiliary supply voltage (3.3V)
- Negative reference for all voltages.
When only V
V
through an internal low impedance
switch.
input for low impedance switch.
OUT
voltage comes from V
AUX
(3.3V) is present,
AIC1531
AUX
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