Capacitor Charger. AAT4621 Datasheet

AAT4621 Charger. Datasheet pdf. Equivalent


AAT AAT4621
www.DataSheet4U.com
General Description
The AAT4621 SmartSwitch 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 conjunc-
tion with a super capacitor, the AAT4621 will
ensure that the power ratings of the PCMCIA host
are not exceeded at any time. Featuring two inde-
pendent, programmable current limits and a power
loop, the AAT4621 can ensure that the super
capacitor can be charged without exceeding PCM-
CIA 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 hys-
teresis is provided with the addition of an external
resistor. The quiescent supply current is typically a
low 40µA. In shutdown mode, the supply current
decreases to less than 1µA.
The AAT4621 is available in a thermally enhanced,
Pb-free, 12-pin TSOPJW or 14-pin TDFN33 pack-
age and is specified over the -40°C to 85°C tem-
perature range.
AAT4621
PC Card Current Limit Interface
and Capacitor Charger
Features
SmartSwitch
• VIN Range: 3.0V to 5.5V
• Dual Independent Current Limits
— 75mA to 1200mA
— ±10% Current Accuracy
— 20°C Temperature Band
• Reverse Current Blocking Protection
• Power Loop
• Low Quiescent Current
— 40µA Typical
— 1.0µA Max with Switch Off
• 65mΩ Typical RDS(ON) at 3V
• Only 1.4V Needed for Enable Control Pin
• System READY Output with Externally
Programmable Hysteresis
• Under-Voltage Lockout
• Temperature Range: -40 to 85°C
• 12-Pin TSOPJW Package or 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
V CC
ENSUPERCAP
EN OPERATION
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
100kΩ
To Load
To μC
ISETL
ISETU
RSETU
RSETL
SuperCap
4621.2007.07.1.0
1


AAT4621 Datasheet
Recommendation AAT4621 Datasheet
Part AAT4621
Description PC Card Current Limit Interface and Capacitor Charger
Feature AAT4621; www.DataSheet4U.com AAT4621 PC Card Current Limit Interface and Capacitor Charger General Descript.
Manufacture AAT
Datasheet
Download AAT4621 Datasheet




AAT AAT4621
AAT4621
PC Card Current Limit Interface
and Capacitor Charger
Pin Descriptions
Pin #
TSOPJW-12 TDFN33-14
1 14
2 13
3
4, 5, 6
12
8, 9, 10, 11
7, 8 5, 6, 7
94
10 3
11 2
12 1
Symbol
EN IU
EN IL
GND
VCC
OUT
ISETL
ISETU
RHYS
RDY
Function
Enable input. Active low enable with internal pull up. Also switches in the
higher current limit to allow the System to start functioning. Can be directly
connected to System Ready for automatic enabling. When both EN IL B and
EN IU B are enabled, ISETU will be selected.
Enable input. Active low enable with internal pull up. Also switches in the
lower current limit initiating the super capacitor to start charging.
Device ground connection.
Input pins to the P-channel MOSFET source. Connect 1µF capacitor from
VCC to GND.
P-channel MOSFET drain connection. Connect to super capacitor from OUT
to GND.
Lower current-limit set input. A resistor from ISETU to ground sets the
maximum lower current limit for the switch. Current limit can be set between
75mA and 1200mA.
Upper current limit set input. A resistor from ISETL to ground sets the
maximum upper current limit for the switch. Current limits can be set
between 75mA and 1200mA. Connect to ground to disable current limit.
System READY hysteresis. Connect a resistor to ground to set the System
Ready comparator hysteresis.
System ready pin. Open drain, active low, initiated when the capacitor is 98%
charged.
Pin Configuration
TSOPJW-12
(Top View)
EN IU
EN IL
GND
VCC
VCC
VCC
1
2
3
4
5
6
12 RDY
11 RHYS
10 ISETU
9 ISETL
8 OUT
7 OUT
TDFN33-14
(Top View)
RDY 1
RHYS 2
ISETU 3
ISETL 4
OUT 5
OUT 6
OUT 7
14 ENIU
13 ENIL
12 GND
11 VCC
10 VCC
9 VCC
8 VCC
2 4621.2007.07.1.0



AAT AAT4621
AAT4621
PC Card Current Limit Interface
and Capacitor Charger
Absolute Maximum Ratings1
Symbol
VCC
VEN
VSET, VOUT
IMAX
Description
VCC to GND
EN to GND
SET, OUT to GND
Maximum Continuous Switch Current
Value
-0.3 to 6
-0.3 to VCC + 0.3
-0.3 to VCC + 0.3
2.5
Units
V
V
V
A
Thermal Characteristics
Symbol
θJA
Description
Maximum Thermal Resistance2
PD Maximum Power Dissipation2
TJ Operating Junction Temperature Range
TSOPJW-12
TDFN33-14
TSOPJW-12
TDFN33-14
Value
160
50
625
2
-40 to 150
Units
°C/W
mW
W
°C
1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at condi-
tions other than the operating conditions specified is not implied. Only one Absolute Maximum Rating should be applied at any one time.
2. Mounted on an FR4 board.
4621.2007.07.1.0
3







@ 2014 :: Datasheetspdf.com :: Semiconductors datasheet search & download site (Privacy Policy & Contact)