UZXYY ANALOGICTECH [Advanced Analogic Technologies], UZXYY Datasheet - Page 9

• Manufacturer Part Number: UZXYY
• Description: PCMCIA Current Limit Interface and Capacitor Charger
• Manufacturer: ANALOGICTECH [Advanced Analogic Technologies]

Functional Block Diagram
Functional Description
The AAT4620 is an integrated P-channel MOSFET
load switch with an upper and lower adjustable cur-
rent limits which can be enabled independently,
over temperature protection, a power loop and a
super capacitor charger. The current limit control is
combined with an over temperature thermal limit
and power loop circuit to provide a comprehensive
system to protect the load switch and its supply
from load conditions which exceed the supply spec-
ifications. The AAT4620 has been designed specif-
ically to provide the interface between a PCMCIA
4620.2007.04.1.1
EN IU
EN IL
VCC
Reference
Lockout
Voltage
Under-
GND
1.2V
Reverse
Blocking
Current Limit
Control
Over-Temp
Protection
host and PCMCIA card where a super capacitor has
been used to "average out" high pulse currents
which would otherwise exceed the PCMCIA/
Express Card power specifications. e.g. GSM/
GPRS modem cards, where pulse currents during
transmit signals can exceed the 1A maximum spec-
ification (1.3A in the case of Express Card).
The current limit and over temperature circuits act
independently. The device current limit is activated
when the output load current exceeds an internal
threshold level. There are two internal current lim-
its which are enabled independently. The current
limit threshold in each case is determined by exter-
PCMCIA Current Limit Interface
RHYS
Power
Loop
and Capacitor Charger
OUT
RDY
ISETL
ISETU
AAT4620
9