AAT4621_12 Datasheet, PDF (1/17 Pages) Skyworks Solutions Inc. – PC Card Current Limit Interface and Capacitor Charger

DATA SHEET
AAT4621
PC Card Current Limit Interface and Capacitor Charger
General Description
The AAT4621 SmartSwitch family is a current limited
P-channel MOSFET power switch designed for high-side
load-switching applications in PC Card GSM/GPRS/3G
modem cards. Used in conjunction with a super capaci-
tor, the AAT4621 will ensure that the power ratings of
the PCMCIA host are not exceeded at any time. Featuring
two independent, programmable current limits and a
power loop, the AAT4621 can ensure that the super
capacitor can be charged without exceeding PCMCIA
specifications. The current limit is set by two external
resistors allowing a ±10% current limit accuracy over
the normal operating temperature range. The switch can
be controlled from either of the two enable inputs and in
the off condition will block currents in both directions.
The AAT4621 also incorporates a System READY function
which can advise the system that the super capacitor is
fully charged and ready for use. Adjustable hysteresis is
provided with the addition of an external resistor. The
quiescent supply current is typically a low 40μA. In shut-
down mode, the supply current decreases to less than
1μA. The AAT4621 has a current limit range from 75mA
to 1200mA; the AAT4621-1 has a current limit range
from 150mA to 2400mA.
The AAT4621 is available in a thermally enhanced,
Pb-free 14-pin TDFN33 package and is specified over the
-40°C to 85°C temperature range.
Features
• Operating Voltage Range: 3.0V to 5.5V
• Dual Independent Current Limits
▪ AAT4621: 75mA to 1200mA
▪ AAT4621-1: 150mA to 2400mA
▪ ±10% Current Accuracy
• Reverse Current Blocking Protection
• Power Loop
• Low Quiescent Current
▪ 40μA Typical
▪ 1.0μA Max with Switch Off
• 65m Typical R_DS(ON) at 3V
• System READY Output with Externally Programmable
Hysteresis
• Only 1.4V Needed for Enable Control Pin
• Under-Voltage Lockout
• Over-Temperature Protection
• Temperature Range: -40 to 85°C
• 14-Pin TDFN33 Package
Applications
• Capacitor Charger
• CF Card Port Power Protection
• Express Card GSM/GPRS/3G Modems
• PC Card GSM/GPRS Class 10/12 Modems
• WiMAX Cards
Typical Application
VCC
ENIL
ENIU
VCC
EN IL
Under-
Voltage
Lockout
Reverse
Blocking
Over-Temp
Protection
Power
Loop
EN IU
1.2V
Reference
GND
Current
Limit
Control
RHYS
OUT
RDY
100k
To Load
To μC
ISETL
ISETU
RSETU
RSETL
SuperCap
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
201944A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • May 15, 2012
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