AAT AAT3242ITP-QN-T1 300ma/150ma dual cmos ldo linear regulator Datasheet

AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
PowerLinear™
General Description
Features
The AAT3242 is a dual low dropout linear regulator
with Power OK (POK) outputs. Two integrated regulators provide a high power 300mA output and a
lower power 150mA output, making this device
ideal for use with microprocessors and DSP cores
in portable products. Two POK pins provide open
drain output signals when their respective regulator
output is within regulation. The AAT3242 has independent input voltage and enable pins for increased
design flexibility. This device features a very low
quiescent current (140µA typical) and low dropout
voltages (typically 200mV and 400mV at the full
output current level), making it ideal for portable
applications where extended battery life is critical.
The AAT3242 has complete over-current/short-circuit and over-temperature protection circuits to
guard against extreme operating conditions.
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The AAT3242 is available in a space-saving, Pbfree, 12-pin TSOPJW package. This device is
capable of operation over the -40°C to +85°C temperature range.
Applications
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High/Low Current Outputs, 300mA/150mA
Low Dropout:
— LDO A: 400mV at 300mA
— LDO B: 200mV at 150mA
High Output Voltage Accuracy: ±1.5%
High PSRR: 65dB at 1kHz
70µA Quiescent Current for Each LDO
Over-Current/Short-Circuit Protection
Over-Temperature Protection
Two POK Outputs
Independent Power and Enable Inputs
Uses Low Equivalent Series Resistance
(ESR) Ceramic Capacitors
12-Pin TSOPJW Package
-40°C to +85°C Temperature Range
Cellular Phones
Digital Cameras
Handheld Instruments
Microprocessor / DSP Core / I/O Power
Notebook Computers
PDAs and Handheld Computers
Portable Communication Devices
Typical Application
VIN
INA
AAT3242
Enable A
ENA
OUTPUT A
OUTA
100kΩ
POKA
POKA
OUTPUT B
OUTB
INB
100kΩ
POKB
Enable B
3242.2006.04.1.10
ENB
GND
POKB
2.2μF
2.2μF
1
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
Pin Descriptions
Pin #
Symbol
Function
1
ENA
Enable Regulator A pin; this pin should not be left floating. When pulled
low, the PMOS pass transistor turns off and the device enters shutdown
mode, consuming less than 1µA.
2, 3, 8, 9
GND
Ground connection pins.
4
POKA
Power OK pin with open drain output. It is pulled low when the OUTA pin is
below the 10% regulation window.
5
OUTB
Low current (150mA) regulator output pin; should be decoupled with a
2.2µF or greater output low-ESR ceramic capacitor.
6
INB
Input voltage pin for Regulator B; should be decoupled with 1µF or greater
capacitor.
7
ENB
Enable Regulator B; this pin should not be left floating. When pulled low, the
PMOS pass transistor turns off and the device enters shutdown mode, consuming less than 1µA.
10
POKB
Power OK pin with open drain output. It is pulled low when the OUTB pin is
below the 10% regulation window.
11
OUTA
High-current (300mA) regulator output pin; should be decoupled with a
2.2µF or greater output low-ESR ceramic capacitor.
12
INA
Input voltage pin for Regulator A; should be decoupled with 1µF or greater
capacitor.
Pin Configuration
TSOPJW-12
(Top View)
ENA
GND
GND
POKA
OUTB
INB
2
1
12
2
11
3
10
4
9
5
8
6
7
INA
OUTA
POKB
GND
GND
ENB
3242.2006.04.1.10
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
Absolute Maximum Ratings1
Symbol
Description
VIN
VENIN(MAX)
IOUT2
TJ
TLEAD
Input Voltage
Maximum EN to Input Voltage
DC Output Current
Operating Junction Temperature Range
Maximum Soldering Temperature (at leads, 10 sec)
Value
Units
6.0
0.3
PD/(VIN - VO)
-40 to 150
300
V
V
mA
°C
°C
Value
Units
110
909
°C/W
mW
Thermal Information
Symbol
θJA
PD
Description
Thermal Resistance3
Maximum Power Dissipation (TA = 25°C)4
1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at conditions other than the operating conditions specified is not implied. Only one Absolute Maximum Rating should be applied at any one time.
2. Based on long-term current density limitation.
3. Mounted on an FR4 board.
4. Derate 9.1mW/°C above 25°C.
3242.2006.04.1.10
3
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
Electrical Characteristics1
VIN = VOUT(NOM) + 1.0V for VOUT options greater than 1.5V. VIN = 2.5V for VOUT ≤ 1.5V. IOUT = 1.0mA, COUT =
2.2µF, CIN = 1.0µF, TA = -40°C to +85°C, unless otherwise noted. Typical values are TA = 25°C.
Symbol
Description
Conditions
Min
Typ Max
Units
LDO A; IOUT = 300mA
VOUT
Output Voltage Tolerance
VIN
VDO
ΔVOUT/
VOUT*ΔVIN
ΔVOUT(Line)
Input Voltage
Dropout Voltage2, 3
Line Regulation4
ΔVOUT(Load)
Dynamic Load Regulation
Dynamic Line Regulation
VEN(L)
VEN(H)
VPOK
VPOKHYS
VPOK(LO)
IPOK
IOUT
ISC
IQ
ISD
Enable Threshold Low
Enable Threshold High
Power OK Trip Threshold
Power OK Hysteresis
Power OK Output Voltage Low
POK Output Leakage Current
Output Current
Short-Circuit Current
Ground Current
Shutdown Current
PSRR
Power Supply Rejection Ratio
TSD
Over-Temperature Shutdown
Threshold
Over-Temperature Shutdown
Hysteresis
Output Noise
Output Voltage Temperature
Coefficient
THYS
eN
TC
IOUT = 1mA
to 300mA
TA = 25°C
TA = -40 to 85°C
-1.5
-2.5
VOUT + VDO5
1.5
2.5
5.5
600
0.09
%
V
mV
%/V
IOUT = 300mA
VIN = VOUT + 1 to 5.0 V
400
IOUT = 300mA, VIN = VOUT + 1
to VOUT + 2, TR/TF = 2µS
IOUT = 1mA to 300mA,
TR <5µS
5.0
mV
60
mV
0.6
VOUT Rising, TA = 25°C
ISINK = 1mA
VPOK < 5.5V, VOUT in Regulation
VOUT > 1.2V
VOUT < 0.4V
VIN = 5V, No Load; EN A = VIN
VIN = 5V, EN A = 0V
1kHz
IOUT =1 0mA 10kHz
1MHz
eNBW = 300Hz to 50kHz
1.5
90
94
1.0
98
0.4
1.0
300
600
70
65
45
42
145
125
1.0
V
V
% of VOUT
% of VOUT
V
µA
mA
mA
µA
µA
dB
°C
12
°C
250
22
µVRMS
ppm/°C
1. The AAT3242 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured
by design, characterization, and correlation with statistical process controls.
2. VDO is defined as VIN - VOUT when VOUT is 98% of nominal.
3. For VOUT < 2.1V, VDO = 2.5 - VOUT.
4. CIN = 10µF.
5. To calculate minimum input voltage, use the following equation: VIN(MIN) = VOUT(MAX) + VDO(MAX) as long as VIN ≥ 2.5V.
4
3242.2006.04.1.10
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
Electrical Characteristics1 (continued)
VIN = VOUT(NOM) + 1.0V for VOUT options greater than 1.5V. VIN = 2.5V for VOUT ≤ 1.5V. IOUT = 1.0mA, COUT =
2.2µF, CIN = 1.0µF, TA = -40°C to +85°C, unless otherwise noted. Typical values are TA = 25°C.
Symbol
Description
Conditions
Min
Typ Max
Units
LDO B; IOUT = 150mA
VOUT
Output Voltage Tolerance
VIN
VDO
ΔVOUT/
VOUT*ΔVIN
ΔVOUT(Line)
Input Voltage
Dropout Voltage2, 3
Line Regulation4
ΔVOUT(Load)
VEN(L)
VEN(H)
VPOK
VPOKHYS
VPOK(LO)
IPOK
IOUT
ISC
IQ
Dynamic Load Regulation
Enable Threshold Low
Enable Threshold High
Power OK Trip Threshold
Power OK Hysteresis
Power OK Output Voltage Low
POK Output Leakage Current
Output Current
Short-Circuit Current
Ground Current
PSRR
Power Supply Rejection Ratio
TSD
Over-Temperature Shutdown
Threshold
Over-Temperature Shutdown
Hysteresis
Output Noise
Output Voltage Temperature
Coefficient
THYS
eN
TC
Dynamic Line Regulation
IOUT = 1mA
to 150mA
TA = 25°C
TA = -40 to 85°C
-1.5
-2.5
VOUT + VDO5
IOUT = 150mA
VIN = VOUT + 1 to 5.0 V
200
IOUT = 150mA, VIN = VOUT + 1
to VOUT + 2, TR/TF = 2µS
IOUT = 1mA to 150mA, TR <5µS
5.0
1.5
2.5
5.5
300
0.09
60
ISINK = 1mA
VPOK < 5.5V, VOUT in Regulation
VOUT > 1.2V
VOUT < 0.4V
VIN = 5V, No Load; EN B = VIN
1kHz
IOUT = 10mA 10kHz
1MHz
eNBW = 300Hz to 50kHz
1.5
90
94
1.0
98
0.4
1.0
150
600
70
65
45
42
145
V
mV
%/V
mV
0.6
VOUT Rising, TA = 25°C
%
125
mV
V
V
% of VOUT
% of VOUT
V
µA
mA
mA
µA
dB
°C
12
°C
250
22
µVRMS
ppm/°C
1. The AAT3242 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured
by design, characterization, and correlation with statistical process controls.
2. VDO is defined as VIN - VOUT when VOUT is 98% of nominal.
3. For VOUT < 2.3V, VDO = 2.5 - VOUT.
4. CIN = 10µF.
5. To calculate minimum input voltage, use the following equation: VIN(MIN) = VOUT(MAX) + VDO(MAX) as long as VIN ≥ 2.5V.
3242.2006.04.1.10
5
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
Typical Characteristics
Unless otherwise noted, VIN = 5V, TA = 25°C.
Dropout Characteristics
Dropout Voltage vs. Temperature
3.20
IL = 300mA
480
Output Voltage (V)
Dropout Voltage (mV)
540
420
360
300
IL = 100mA
IL = 150mA
240
180
120
60
-40 -30 -20 -10 0
2.80
IOUT = 300mA
IOUT = 150mA
2.60
2.40
IOUT = 10mA
2.20
IL = 50mA
0
IOUT = 0mA
3.00
2.00
2.70
10 20 30 40 50 60 70 80 90 100 110 120
2.80
IOUT = 100mA
IOUT = 50mA
2.90
Temperature (°C)
Ground Current (μA)
450
Dropout Voltage (mV)
3.20
3.30
90
500
400
350
300
85°C
250
200
25°C
150
-40°C
100
80
70
60
IOUT = 300mA
50
IOUT = 150mA
IOUT = 50mA
40
IOUT = 0mA
30
IOUT = 10mA
20
10
50
0
0
0
50
100
150
200
250
300
2
2.5
3
3.5
4
4.5
Output Current (mA)
Input Voltage (V)
Quiescent Current vs. Temperature
Output Voltage vs. Temperature
5
1.203
100
90
1.202
80
Output Voltage (V)
Quiescent Current (μA)
3.10
Ground Current vs. Input Voltage
Dropout Voltage vs. Output Current
70
60
50
40
30
20
10
0
-40 -30 -20 -10
0
10 20 30 40 50 60 70 80 90 100 110 120
Temperature (°C)
6
3.00
Input Voltage (V)
1.201
1.200
1.199
1.198
1.197
1.196
-40 -30 -20 -10
0
10 20
30
40
50 60
70 80
90 100
Temperature (°C)
3242.2006.04.1.10
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
Typical Characteristics
Unless otherwise noted, VIN = 5V, TA = 25°C.
Turn-On Time and POK Delay
Line Transient Response
6
VENABLE (2V/div)
VOUT (500mV/div)
VPOK (500mV/div)
Time (10μs/div)
VIN
3.15
3
3.10
2
3.05
1
0
3.00
VOUT
2.90
-2
2.85
Time (100μs/div)
Load Transient Response 300mA
2.80
300
2.75
200
2.70
100
2.65
IOUT
0
2.60
Output Voltage (V)
400
VOUT
3.00
800
2.90
700
2.80
2.70
500
2.60
400
2.50
300
2.40
2.30
200
IOUT
100
2.20
-100
0
2.10
Time (100μs/div)
-100
Time (10μs/div)
Over-Current Protection
POK Output Response
1200
Output Current (mA)
VIN (2V/div)
VOUT (2V/div)
VPOK (1V/div)
1000
800
600
400
200
0
-200
Time (200μs/div)
3242.2006.04.1.10
600
VOUT
Output Current (mA)
Output Voltage (V)
500
Output Current (mA)
2.85
2.95
-1
Load Transient Response
2.90
3.20
4
Output Voltage (V)
Input Voltage (V)
5
3.25
Time (20ms/div)
7
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
Typical Characteristics
Unless otherwise noted, VIN = 5V, TA = 25°C.
10
1.250
1.225
1.200
1
0.1
1.175
VEN(H)
1.150
1.125
VEN(L)
1.100
1.075
0.01
0.01
0.1
1
10
Frequency (kHz)
8
VEN(H) and V EN(L) vs. VIN
VEN (V)
Noise Amplitude (μV/rtHz)
Self Noise
100
1000
1.050
2.5
3.0
3.5
4.0
4.5
5.0
5.
Input Voltage (V)
3242.2006.04.1.10
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
Functional Block Diagram
INA
OUTA
Over-Current
Protection
ENA
+
Error
Amplifier
-
Over Temperature
Protection
Voltage
Reference
POKA
+
91%
VREF
OUTB
INB
Over-Current
Protection
Over Temperature
Protection
ENB
+
Error
Amplifier
-
Voltage
Reference
POKB
+
91%
VREF
GND
Functional Description
The AAT3242 is a high performance dual LDO regulator with two Power OK pins. The first regulator
(A) sources 300mA of current, while the second (B)
regulator can deliver 150mA. Each regulator has
an integrated Power OK comparator which indicates when the respective output is out of regulation. The POK pins are open drain outputs, and
they are held low when the respective regulator is
in shutdown mode.
3242.2006.04.1.10
The device has independent enable pins to shut
down each LDO regulator for power conservation
in portable products. Forcing EN A/B low (<0.6V)
powers down the regulators and draws a maximum
of 1.0µA. The AAT3242 has short-circuit and thermal protection in case of adverse operating conditions. Device power dissipation is limited to the
package type and thermal dissipation properties.
Refer to the Thermal Considerations section of this
datasheet for details on device operation at maximum output current loads.
9
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
Applications Information
To assure the maximum possible performance is
obtained from the AAT3242, please refer to the following application recommendations.
greater for COUT. If desired, COUT may be increased
without limit. In low output current applications
where output load is less than 10mA, the minimum
value for COUT can be as low as 0.47µF.
Capacitor Characteristics
Input Capacitor
A 1µF or larger capacitor is typically recommended
for CIN in most applications. A CIN capacitor is not
required for basic LDO regulator operation; however, if the AAT3242 is physically located more than
three centimeters from an input power source, a
CIN capacitor will be needed for stable operation.
CIN should be located as closely to the device VIN
pin as practically possible. CIN values greater than
1µF will offer superior input line transient response
and will assist in maximizing the highest possible
power supply ripple rejection.
Ceramic, tantalum, or aluminum electrolytic capacitors may be selected for CIN. There is no specific
capacitor ESR requirement for CIN; however, for
300mA LDO regulator output operation, ceramic
capacitors are recommended for CIN due to their
inherent capability over tantalum capacitors to withstand input current surges from low impedance
sources such as batteries in portable devices.
Output Capacitor
For proper load voltage regulation and operational
stability, a capacitor is required between pins VOUT
and GND. The COUT capacitor connection to the
LDO regulator ground pin should be made as direct
as practically possible for maximum device performance. The AAT3242 has been specifically
designed to function with very low ESR ceramic
capacitors. For best performance, ceramic capacitors are recommended.
Typical output capacitor values for maximum output current conditions range from 1µF to 10µF.
Applications utilizing the exceptionally low output
noise and optimum power supply ripple rejection
characteristics of the AAT3242 should use 2.2µF or
10
Ceramic composition capacitors are highly recommended over all other types of capacitors for use
with the AAT3242. Ceramic capacitors offer many
advantages over their tantalum and aluminum electrolytic counterparts. A ceramic capacitor typically
has very low ESR, is lower cost, has a smaller PCB
footprint, and is non-polarized. Line and load transient response of the LDO regulator is improved by
using low ESR ceramic capacitors. Since ceramic
capacitors are non-polarized, they are not prone to
incorrect connection damage.
Equivalent Series Resistance
ESR is a very important characteristic to consider
when selecting a capacitor. ESR is the internal
series resistance associated with a capacitor that
includes lead resistance, internal connections, size
and area, material composition, and ambient temperature. Typically, capacitor ESR is measured in
milliohms for ceramic capacitors and can range to
more than several ohms for tantalum or aluminum
electrolytic capacitors.
Ceramic Capacitor Materials
Ceramic capacitors less than 0.1µF are typically
made from NPO or C0G materials. NPO and C0G
materials generally have tight tolerance and are
very stable over temperature. Larger capacitor values are usually composed of X7R, X5R, Z5U, or
Y5V dielectric materials. These two material types
are not recommended for use with LDO regulators
since the capacitor tolerance can vary more than
±50% over the operating temperature range of the
device. A 2.2µF Y5V capacitor could be reduced to
1µF over temperature; this could cause problems
for circuit operation. X7R and X5R dielectrics are
much more desirable. The temperature tolerance
3242.2006.04.1.10
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
of X7R dielectric is better than ±15%. Capacitor
area is another contributor to ESR. Capacitors
which are physically large in size will have a lower
ESR when compared to a smaller sized capacitor
of an equivalent material and capacitance value.
These larger devices can improve circuit transient
response when compared to an equal value capacitor in a smaller package size. Consult capacitor
vendor datasheets carefully when selecting capacitors for LDO regulators.
POK Output
The AAT3242 features integrated Power OK comparators which can be used as an error flag. The
POK open drain output goes low when output voltage is 6% (typ) below its nominal regulation voltage. Additionally, any time one of the regulators is
in shutdown, the respective POK output is pulled
low. Connect a pull-up resistor from POKA to
OUTA, and POKB to OUTB.
Enable Function
The AAT3242 features an LDO regulator enable/disable function. Each LDO has its own dedicated
enable pin. These pins (EN) are active high and are
compatible with CMOS logic. To assure the LDO
regulators will switch on, ENA/B must be greater
than 1.6V. The LDO regulators will shut down when
the voltage on the ENA/B pins falls below 0.6V. In
shutdown, the AAT3242 will consume less than
1.0µA of current. If the enable function is not needed in a specific application, it may be tied to VIN to
keep the LDO regulator in a continuously on state.
When the LDO regulators are in shutdown mode,
an internal 20Ω resistor is connected between
VOUT and GND. This is intended to discharge COUT
when the LDO regulators are disabled. The internal
20Ω has no adverse effects on device turn-on time.
Short-Circuit Protection
The AAT3242 contains internal short-circuit protection that will trigger when the output load current
exceeds the internal threshold limit. Under shortcircuit conditions, the output of the LDO regulator
will be current limited until the short-circuit condi-
3242.2006.04.1.10
tion is removed from the output or LDO regulator
package power dissipation exceeds the device
thermal limit.
Thermal Protection
The AAT3242 has an internal thermal protection circuit which will turn on when the device die temperature exceeds 145°C. The LDO regulator output will
remain in a shutdown state until the internal die
temperature falls back below the 145°C trip point.
The combination and interaction between the shortcircuit and thermal protection systems allows the
LDO regulators to withstand indefinite short-circuit
conditions without sustaining permanent damage.
No-Load Stability
The AAT3242 is designed to maintain output voltage regulation and stability under operational noload conditions. This is an important characteristic
for applications where the output current may drop
to zero.
Reverse Output-to-Input Voltage
Conditions and Protection
Under normal operating conditions, a parasitic diode
exists between the output and input of the LDO regulator. The input voltage should always remain
greater than the output load voltage maintaining a
reverse bias on the internal parasitic diode.
Conditions where VOUT might exceed VIN should be
avoided since this would forward bias the internal
parasitic diode and allow excessive current flow into
the VOUT pin, possibly damaging the LDO regulator.
In applications where there is a possibility of VOUT
exceeding VIN for brief amounts of time during normal operation, the use of a larger value CIN capacitor is highly recommended. A larger value of CIN with
respect to COUT will effect a slower CIN decay rate
during shutdown, thus preventing VOUT from
exceeding VIN. In applications where there is a
greater danger of VOUT exceeding VIN for extended
periods of time, it is recommended to place a
Schottky diode across VIN to VOUT (connecting the
cathode to VIN and anode to VOUT). The Schottky
diode forward voltage should be less than 0.45V.
11
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
Thermal Considerations and High
Output Current Applications
The AAT3242 is designed to deliver continuous
output load currents of 300mA and 150mA under
normal operations, and can supply up to 500mA
during circuit start-up conditions. This is desirable
for circuit applications where there might be a brief
high in-rush current during a power-on event.
The limiting characteristic for the maximum output
load current safe operating area is essentially
package power dissipation and the internal preset
thermal limit of the device. In order to obtain high
operating currents, careful device layout and circuit
operating conditions need to be taken into account.
The following discussions will assume the LDO
regulator is mounted on a printed circuit board utilizing the minimum recommended footprint as stated in the layout considerations section of this document. At any given ambient temperature (TA), the
maximum package power dissipation can be determined by the following equation:
PD(MAX) =
TJ(MAX) - TA
θJA
Constants for the AAT3242 are TJ(MAX) (the maximum junction temperature for the device, which is
125°C) and θJA = 110°C/W (the package thermal
resistance). Typically, maximum conditions are calculated at the maximum operating temperature of TA
= 85°C and under normal ambient conditions where
TA = 25°C. Given TA = 85°C, the maximum package
power dissipation is 364mW. At TA = 25°C, the maximum package power dissipation is 909mW.
The maximum continuous output current for the
AAT3242 is a function of the package power dissipation and the input-to-output voltage drop across
the LDO regulator. To determine the maximum
output current for a given output voltage, refer to
the following equation. This calculation accounts
for the total power dissipation of the LDO regulator,
including that caused by ground current.
PD(MAX) = [(VIN - VOUTA)IOUTA + (VIN x IGND)] + [(VIN - VOUTB)IOUTB + (VIN x IGND)]
This formula can be solved for IOUTA to determine the maximum output current for LDOA:
IOUTA(MAX) =
12
PD(MAX) - (2×VIN × IGND) - (VIN - VOUTB) × IOUTB
VIN - VOUTA
3242.2006.04.1.10
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
The following is an example for a 2.5V output:
VOUTA
= 2.5V
VOUTB
= 1.5V
IOUTB
= 150mA
VIN
= 4.2V
IGND
= 125μA
IOUTA(MAX) =
909mW - (2 × 4.2V × 125μA) - (4.2 - 1.5) × 150mA
4.2 - 2.5
IOUTA(MAX) = 296mA
From the discussion above, PD(MAX) was determined to equal 909mW at TA = 25°C.
Therefore, with Regulator B delivering 150mA at 1.5V, Regulator A can sustain a constant 2.5V output at a
296mA load current at an ambient temperature of 25°C. Higher input-to-output voltage differentials can be
obtained with the AAT3242, while maintaining device functions within the thermal safe operating area. To
accomplish this, the device thermal resistance must be reduced by increasing the heat sink area or by operating the LDO regulator in a duty-cycled mode.
For example, an application requires VIN = 4.2V while VOUT = 1.5V at a 500mA load and TA = 25°C. To maintain this high input voltage and output current level, the LDO regulator must be operated in a duty-cycled mode.
Refer to the following calculation for duty-cycle operation:
IGND = 125µA
IOUT = 500mA
VIN
= 4.2V
VOUT = 1.5V
%DC =
100(PD(MAX))
[(VIN - VOUTA)IOUTA + (VIN × IGND)] + [(VIN - VOUTB)IOUTB + (VIN × IGND)]
%DC =
100(909mW)
[(4.2V - 1.5V)500mA + (4.2V × 125μA)] + [(4.2V - 1.5V)200mA + (4.2V × 125μA)]
%DC = 48.10%
PD(MAX) is assumed to be 909mW
For a 500mA output current and a 2.7V drop across the AAT3242 at an ambient temperature of 25°C, the maximum on-time duty cycle for the device would be 48.10%.
3242.2006.04.1.10
13
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
Ordering Information
Voltage
LDO A
LDO B
Package
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
TSOPJW-12
3.3V
3.3V
3.0V
3.0V
3.0V
3.0V
2.9V
2.8V
2.8V
2.8V
2.8V
2.8V
2.8V
2.7V
2.6V
2.5V
1.8V
1.8V
1.8V
2.5V
1.8V
2.85V
2.5V
1.8V
1.5V
1.5V
3.0V
2.8V
2.6V
2.5V
1.9V
1.5V
2.7V
1.8V
1.8V
1.5V
2.7V
2.8V
Marking1
Part Number (Tape and Reel)2
LSXYY
PAXYY
LPXYY
LJXYY
LHXYY
NTXYY
MOXYY
LVXYY
LDXYY
LQXYY
LLXYY
LRXYY
MCXYY
LOXYY
MJXYY
SGXYY
AAT3242ITP-WN-T1
AAT3242ITP-WI-T1
AAT3242ITP-TR-T1
AAT3242ITP-TN-T1
AAT3242ITP-TI-T1
AAT3242ITP-TG-T1
AAT3242ITP-SG-T1
AAT3242ITP-QT-T1
AAT3242ITP-QQ-T1
AAT3242ITP-QO-T1
AAT3242ITP-QN-T1
AAT3242ITP-QY-T1
AAT3242ITP-QG-T1
AAT3242ITP-PP-T1
AAT3242ITP-OI-T1
AAT3242ITP-IN-T1
AAT3242ITP-IG-T1
AAT3242ITP-IP-T1
AAT3242ITP-IQ-T1
PZXYY
RRXYY
All AnalogicTech products are offered in Pb-free packaging. The term “Pb-free” means
semiconductor products that are in compliance with current RoHS standards, including
the requirement that lead not exceed 0.1% by weight in homogeneous materials. For more
information, please visit our website at http://www.analogictech.com/pbfree.
Legend
Voltage
Code
1.5
1.8
1.9
2.5
2.6
2.7
2.8
2.85
2.9
3.0
3.3
G
I
Y
N
O
P
Q
R
S
T
W
1. XYY = assembly and date code.
2. Sample stock is generally held on part numbers listed in BOLD.
14
3242.2006.04.1.10
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
Package Information
TSOPJW-12
2.85 ± 0.20
2.40 ± 0.10
0.10
0.20 +- 0.05
0.50 BSC 0.50 BSC 0.50 BSC 0.50 BSC 0.50 BSC
7° NOM
0.055 ± 0.045
0.04 REF
0.15 ± 0.05
+ 0.10
1.00 - 0.065
0.9625 ± 0.0375
3.00 ± 0.10
4° ± 4°
0.45 ± 0.15
0.010
2.75 ± 0.25
All dimensions in millimeters.
3242.2006.04.1.10
15
AAT3242
300mA/150mA Dual CMOS LDO Linear Regulator
© Advanced Analogic Technologies, Inc.
AnalogicTech cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AnalogicTech product. No circuit patent licenses, copyrights, mask work rights,
or other intellectual property rights are implied. AnalogicTech reserves the right to make changes to their products or specifications or to discontinue any product or service without notice.
Customers are advised to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. All products are sold
subject to the terms and conditions of sale supplied at the time of order acknowledgement, including those pertaining to warranty, patent infringement, and limitation of liability. AnalogicTech
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Advanced Analogic Technologies, Inc.
830 E. Arques Avenue, Sunnyvale, CA 94085
Phone (408) 737-4600
Fax (408) 737-4611
16
3242.2006.04.1.10
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