ETC AAT3216

AAT3216
150mA MicroPower™ LDO with PowerOK
General Description
Features
The AAT3216 MicroPower™ Low Dropout Linear
Regulator is ideally suited for portable applications
where low noise, extended battery life and small
size are critical. The AAT3216 has been specifically designed for low output noise performance,
fast transient response and high power supply
rejection ratio (PSRR), making it ideal for powering
sensitive RF circuits.
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Low Dropout - 200mV at 150mA
Guaranteed 150mA Output
High accuracy ±1.5%
70µA Quiescent Current
High Power Supply Ripple Rejection
Low self noise
PowerOK (POK) Output
Fast line and load transient response
Short circuit protection
Over-Temperature protection
Uses Low ESR ceramic capacitors
Shutdown mode for longer battery life
Low temperature coefficient
12 Factory programmed output voltages
SOT23 5-pin or SC70-JW 8-pin package
Preliminary Information
Other features include low quiescent current, typically 70µA, and low dropout voltage which is typically less than 200mV at full output current. The
device is output short circuit protected and has a
thermal shutdown circuit for additional protection
under extreme conditions.
PowerLinear™™
SmartSwitch
The AAT3216 also features a low-power shutdown
mode for extended battery life. A Power-OK opendrain output signals when VOUT is in regulation.
The AAT3216 is available in a space saving 5-pin
SOT23 or 8-pin SC70-JW package in 12 factory
programmed voltages of 1.2V, 1.5V, 1.8V, 2.0V,
2.3V, 2.5V, 2.7V, 2.8V, 2.85, 3.0V, 3.3V, or 3.5V.
Applications
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Cellular Phones
Notebook Computers
Desktop Computers
Portable Communication Devices
Personal Portable Electronics
Digital Cameras
Typical Application
VIN
VOUT
IN
OUT
AAT3216
ON/OFF
EN
100k
POK
POK
GND
1µF
GND
3216.2004.01.0.94
2.2µF
GND
1
AAT3216
150mA MicroPower™ LDO with PowerOK
Pin Descriptions
Pin #
Symbol
Function
SOT23-5
SC70JW-8
1
5, 6
IN
2
8
GND
3
7
EN
Enable pin - this pin should not be left floating. When pulled low
the PMOS pass transistor turns off and all internal circuitry
enters low-power mode, consuming less than 1µA.
4
1
POK
Power-OK Output. This open-drain output is low when OUT is out
of regulation. Connect a pull up resistor from POK to OUT or IN.
5
2, 3, 4
OUT
Output pin - should be decoupled with 2.2µF ceramic capacitor.
Input voltage pin - should be decoupled with 1µF or greater
capacitor.
Ground connection pin
Pin Configuration
SOT23-5
(Top View)
OUT
POK
POK
OUT
OUT
OUT
1
8
7
2
2
2
1 5
2
3 4
1
IN
GND
EN
SC70JW-8
(Top View)
3
6
4
5
GND
EN
IN
IN
3216.2004.01.0.94
AAT3216
150mA MicroPower™ LDO with PowerOK
Absolute Maximum Ratings
(TA=25°C unless otherwise noted)
Symbol
Description
VIN, POK
IOUT
TJ
Input Voltage, POK
DC Output Current
Operating Junction Temperature Range
Value
Units
6
PD/(VIN-VO)
-40 to 150
V
mA
°C
Note: 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.
Thermal Information
Symbol
ΘJA
PD
Description
Maximum Thermal Resistance (SOT23-5, SC70JW-8)
Maximum Power Dissipation1 (SOT23-5, SC70JW-8)
1
Rating
Units
190
526
°C/W
mW
Note 1: Mounted on a demo board.
Recommended Operating Conditions
Symbol
VIN
T
Description
Input Voltage
Ambient Temperature Range
2
Rating
Units
(VOUT + VDO) to 5.5
-40 to +85
V
°C
Note 2: To calculate minimum input voltage, use the following equation: VIN(MIN) = VOUT(MAX) + VDO(MAX) as long as VIN ≥ 2.5V.
3216.2004.01.0.94
3
AAT3216
150mA MicroPower™ LDO with PowerOK
Electrical Characteristics
(VIN=VOUT(NOM)+1V for VOUT options greater than 1.5V. VIN= 2.5 for
VOUT≤1.5V. IOUT=1mA, COUT=2.2µF, CIN=1µf, TA= -40 to 85°C unless otherwise noted. Typical values are at
TA=25°C)
Symbol
Description
Conditions
Output Voltage Tolerance
IOUT = 1mA to 150mA
Output Current
Dropout Voltage 1, 2
Short Circuit Current
Ground Current
Shutdown Current
VOUT > 1.2V
IOUT = 150mA
VOUT < 0.4V
VIN = 5V, No load, EN = VIN
VIN = 5V, EN = 0V
Line Regulation 3
VIN = VOUT + 1 to 5.0V
∆VOUT(line)
Dynamic Line Regulation
∆VOUT(load)
VEN(L)
VEN(H)
IEN
VPOK
VPOKHYS
VPOK(OL)
IPOK
Dynamic Load Regulation
Enable Threshold Low
Enable Threshold High
Leakage Current on Enable Pin
POK Trip Threshold
POK Hysteresis
POK Output Voltage Low
POK Output Leakage Current
VIN=VOUT+1V to VOUT+2V, IOUT=150mA,
TR/TF =2µs
IOUT = 1mA to 150mA, TR<5µs
VOUT
IOUT
VDO
ISC
IQ
ISD
∆VOUT/VOUT*∆VIN
PSRR
TSD
THYS
eN
TC
Power Supply Rejection Ratio
Min Typ Max
TA=25°C
-1.5
TA=-40 to 85°C -2.5
150
1.5
2.5
200
600
70
125
1
%
%
mA
mV
mA
µA
µA
0.09
%/V
300
5
mV
30
mV
V
V
µA
% of VOUT
% of VOUT
V
µA
0.6
1.5
VEN = 5V
VOUT rising, TA = 25°C
ISINK = 1mA
VPOK < 5.5V, VOUT in regulation
1 kHz
IOUT=10mA
10kHz
1MHz
Over Temp Shutdown Threshold
Over Temp Shutdown Hysteresis
Output Noise
Noise Power BW = 300Hz-50kHz
Output Voltage Temp. Coeff.
90
Units
94
1
1
98
0.4
1
65
45
42
145
12
250
22
dB
°C
°C
µVrms/rtHz
ppm/°C
Note 1: VDO is defined as VIN - VOUT when VOUT is 98% of nominal.
Note 2: For VOUT < 2.3V, VDO = 2.5V - VOUT.
Note 3: CIN = 10µF
4
3216.2004.01.0.94
AAT3216
150mA MicroPower™ LDO with PowerOK
Typical Characteristics
(Unless otherwise noted, VIN = 5V, TA = 25°C)
Dropout Characteristics
Dropout Voltage vs. Temperature
260
240
220
200
180
160
140
120
100
80
60
40
20
0
3.00
IL = 150mA
IOUT = 0mA
2.80
V OUT (V)
Dropout Voltage (mV)
3.20
IL = 100mA
IOUT = 10mA
2.60
IOUT = 50mA
2.40
IL = 50mA
-40 -30 -20 -10 0
IOUT = 100mA
IOUT = 150mA
2.20
2.00
2.70
10 20 30 40 50 60 70 80 90 100 110 120
2.80
2.90
3.00
3.10
3.20
VIN (V)
Temperature (°C)
Ground Current vs. Input Voltage
Dropout Voltage vs. Output Current
90.00
80.00
250
70.00
200
IGND (µA)
Dropout Voltage (mV)
300
85°C
150
100
50.00
IOUT=150mA
40.00
IOUT=10mA
20.00
-40°C
IOUT=50mA
IOUT=0mA
30.00
25°C
50
60.00
10.00
0
0
25
50
75
100
125
0.00
150
2
2.5
3
4
4.5
5
Output Voltage vs. Temperature
Quiescent Current vs. Temperature
1.203
100
90
1.202
80
Output Voltage (V)
Quiescent Current (µA)
3.5
VIN (V)
Output Current (mA)
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)
3216.2004.01.0.94
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)
5
AAT3216
150mA MicroPower™ LDO with PowerOK
Typical Characteristics
(Unless otherwise noted, VIN = 5V, TA = 25°C)
Turn Off Time with POK Delay
Turn On Time and POK Delay
VENABLE (2V/div)
VEN (2V/div)
VOUT (500mV/div)
VPOK (2V/div)
VPOK (500mV/div)
VOUT (2V/div)
Time (200µs/div)
Time (10µs/div)
Line Transient Response
Load Transient Response
2.90
6
VIN
3.10
2
3.05
1
3.00
VOUT
2.95
-1
2.90
-2
2.85
400
VOUT
2.80
300
2.75
200
2.70
100
2.65
IOUT (mA)
3.15
3
V OUT (V)
4
0
2.85
3.20
V OUT (V)
5
V IN (V)
500
3.25
0
IOUT
2.60
-100
100 µs/div
Time (100 µs/div)
Over Current Protection
POK Output Response
1200
VIN (2V/div)
1000
IOUT (mA)
800
VOUT (2V/div)
600
400
200
0
VPOK (1V/div)
-200
Time (20 ms/div)
6
Time (200µs/div.)
3216.2004.01.0.94
AAT3216
150mA MicroPower™ LDO with PowerOK
Typical Characteristics
(Unless otherwise noted, VIN = 5V, TA = 25°C)
VEN(H) and V EN(L) vs. VIN
10
1.250
1.225
1.200
1
VEN (V)
Noise Amplitude (µV/rtHz)
AAT3216 Self Noise
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)
3216.2004.01.0.94
100
1000
1.050
2.5
3.0
3.5
4.0
4.5
5.0
5.5
VIN (V)
7
AAT3216
150mA MicroPower™ LDO with PowerOK
Functional Block Diagram
IN
OUT
Over-Current
Protection
Over-Temperature
Protection
Error
Amplifier
EN
POK
Voltage
Reference
94%
GND
Functional Description
The AAT3216 is intended for LDO regulator applications where output current load requirements
range from no load to 150mA.
The advanced circuit design of the AAT3216 provides excellent transient response and fast turn-on
ability. The LDO regulator output has been specifically optimized to function with low cost, low ESR
ceramic capacitors. However, the design will allow
for operation over a wide range of capacitor types.
The AAT3216 has an integrated Power-OK comparator which indicates when the output is out of
regulation.
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The device enable circuit is provided to shutdown
the LDO regulator for power conservation in portable
products. The enable circuit has an additional output capacitor discharge circuit to assure sharp application circuit turn off upon device shutdown.
This LDO regulator has complete short circuit and
thermal protection. The integral combination of
these two internal protection circuits give the
AAT3216 a comprehensive safety system during
extreme adverse operating conditions. Device
power dissipation is limited to the package type
and thermal dissipation properties. Refer to the
thermal considerations discussion in the section for
details on device operation at maximum output current loads.
3216.2004.01.0.94
AAT3216
150mA MicroPower™ LDO with PowerOK
Applications Information
To assure the maximum possible performance is
obtained from the AAT3216, please refer to the following application recommendations.
Input Capacitor
Typically a 1µF or larger capacitor is recommended for CIN in most applications. A CIN capacitor is
not required for basic LDO regulator operation.
However, if the AAT3216 is physically located more
than 3 centimeters from an input power source, a
CIN capacitor will be needed for stable operation.
CIN should be located as close 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
150mA 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 AAT3216 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 AAT3216 should use 2.2µF or
greater for COUT. If desired, COUT may be increased
without limit.
In low output current applications where output
load is less then 10mA, the minimum value for
COUT can be as low as 0.47µF.
3216.2004.01.0.94
Capacitor Characteristics
Ceramic composition capacitors are highly recommended over all other types of capacitors for use
with the AAT3216. 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): ESR is a
very important characteristic to consider when
selecting a capacitor. ESR is the internal series
resistance associated with a capacitor, which
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 COG materials. NPO and COG materials are
typically tight tolerance very stable over temperature. Larger capacitor values are typically composed of X7R, X5R, Z5U and Y5V dielectric materials. Large ceramic capacitors, typically greater
then 2.2µF are often available in the low cost Y5V
and Z5U dielectrics. 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
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.
9
AAT3216
150mA MicroPower™ LDO with PowerOK
Applications Information
Consult capacitor vendor data sheets carefully
when selecting capacitors for LDO regulators.
POK Output
The AAT 3216 features an integrated Power-OK
comparator which can be used as an error flag.
The POK open-drain output goes low when OUT is
6% below its nominal regulation voltage. Connect
a pull-up resistor from POK to OUT or IN. A
delayed POK signal can be implemented with a
capacitor in parallel with the pull-up resistor.
Enable Function
The AAT3216 features an LDO regulator enable/
disable function. This pin (EN) is active high and is
compatible with CMOS logic. To assure the LDO
regulator will switch on, the EN turn on control level
must be greater than 2.0 volts. The LDO regulator
will go into the disable shutdown mode when the
voltage on the EN pin falls below 0.6 volts. 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 regulator is in the shutdown mode,
an internal 1.5kΩ resistor is connected between
VOUT and GND. This is intended to discharge COUT
when the LDO regulator is disabled. The internal
1.5kΩ has no adverse effect on device turn on time.
Short Circuit Protection
The AAT3216 contains an internal short circuit protection circuit that will trigger when the output load
current exceeds the internal threshold limit. Under
short circuit conditions the output of the LDO regulator will be current limited until the short circuit
condition is removed from the output or LDO regulator package power dissipation exceeds the
device thermal limit.
Thermal Protection
The AAT3216 has an internal thermal protection circuit which will turn on when the device die temperature exceeds 150°C. The internal thermal protection circuit will actively turn off the LDO regulator
10
output pass device to prevent the possibility of over
temperature damage. The LDO regulator output
will remain in a shutdown state until the internal die
temperature falls back below the 150°C trip point.
The combination and interaction between the short
circuit and thermal protection systems allow the
LDO regulator to withstand indefinite short circuit
conditions without sustaining permanent damage.
No-Load Stability
The AAT3216 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 then 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 0.45 volts.
Thermal Considerations and High
Output Current Applications
The AAT3216 is designed to deliver a continuous
output load current of 150mA under normal operating conditions.
3216.2004.01.0.94
AAT3216
150mA MicroPower™ LDO with PowerOK
Applications Information
This formula can be solved for VIN to determine the
maximum input voltage.
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 is an example for an AAT3216 set for
a 2.5 volt output:
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 the document.
VOUT = 2.5 volts
IOUT = 150mA
IGND = 150µA
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 AAT3216 are TJ(MAX), the maximum junction temperature for the device which is
125°C and ΘJA = 190°C/W, the package thermal
resistance. Typically, maximum conditions are calculated at the maximum operating temperature
where TA = 85°C, under normal ambient conditions
TA = 25°C. Given TA = 85°, the maximum package
power dissipation is 211mW. At TA = 25°C°, the
maximum package power dissipation is 526mW.
The maximum continuous output current for the
AAT3216 is a function of the package power dissipation and the input to output voltage drop across
the LDO regulator. Refer to the following simple
equation:
IOUT(MAX) < PD(MAX) / (VIN - VOUT)
For example, if VIN = 5V, VOUT = 3V and TA = 25°,
IOUT(MAX) < 264mA. If the output load current were to
exceed 264mA or if the ambient temperature were to
increase, the internal die temperature will increase.
If the condition remained constant, the LDO regulator thermal protection circuit will activate.
To figure what the maximum input voltage would be
for a given load current 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 - VOUT)IOUT + (VIN x IGND)
3216.2004.01.0.94
VIN(MAX) = (PD(MAX) + (VOUT x IOUT)) / (IOUT + IGND)
From the discussion above, PD(MAX) was determined to equal 526mW at TA = 25°C.
VIN(MAX)=(526mW+(2.5Vx150mA))/(150mA +150µA)
VIN(MAX) = 6.00V
Thus, the AAT3216 can sustain a constant 2.5V
output at a 150mA load current as long as VIN is ≤
6.00V at an ambient temperature of 25°C. 6.0V is
the absolute maximum voltage where an AAT3216
would never be operated, thus at 25°C, the device
would not have any thermal concerns or operational VIN(MAX) limits.
This situation can be different at 85°C. The following is an example for an AAT3216 set for a 2.5 volt
output at 85°C:
From the discussion above, PD(MAX) was determined to equal 211mW at TA = 85°C.
VOUT = 2.5 volts
IOUT = 150mA
IGND = 150uA
VIN(MAX)=(211mW+(2.5Vx150mA))/(150mA +150uA)
VIN(MAX) = 3.90V
Higher input to output voltage differentials can be
obtained with the AAT3216, 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 = 2.5V at a 150mA load and TA = 85°C.
VIN is greater than 3.90V, which is the maximum
safe continuous input level for VOUT = 2.5V at
150mA for TA = 85°C. To maintain this high input
voltage and output current level, the LDO regulator
11
AAT3216
150mA MicroPower™ LDO with PowerOK
must be operated in a duty cycled mode. Refer to
the following calculation for duty cycle operation:
Device Duty Cycle vs. V DROP
VOUT = 2.5V @ 25 C
PD(MAX) is assumed to be 211mW
VOUT = 2.5 volt
%DC=100(PD(MAX)/((VIN-VOUT)IOUT+(VINxIGND))
3.5
Voltage Drop (V)
IGND = 150µA
IOUT = 150mA
VIN = 4.2 volts
%DC=100(211mW/((4.2V-2.5V)150mA+(4.2Vx150µA))
3
2.5
200mA
2
1.5
1
0.5
0
0
%DC = 85.54%
10
20
30
40
50
60
70
80
90
100
Duty Cycle (%)
For a 150mA output current and a 2.7volt drop
across the AAT3216 at an ambient temperature of
85°C, the maximum on time duty cycle for the
device would be 85.54%.
Device Duty Cycle vs. VDROP
VOUT= 2.5V @ 50 C
The following family of curves show the safe operating area for duty cycled operation from ambient
room temperature to the maximum operating level.
Voltage Drop (V)
3.5
3
2.5
200mA
2
150mA
1.5
1
0.5
0
0
10
20
30
40
50
60
70
80
90
100
Duty Cycle (%)
Device Duty Cycle vs. VDROP
VOUT = 2.5V @ 85 C
Voltage Drop (V)
3.5
100mA
3
2.5
200mA
2
1.5
150mA
1
0.5
0
0
10
20
30
40
50
60
70
80
90
100
Duty Cycle (%)
12
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AAT3216
150mA MicroPower™ LDO with PowerOK
Applications Information
High Peak Output Current Applications
Some applications require the LDO regulator to
operate at continuous nominal level with short
duration high current peaks. The duty cycles for
both output current levels must be taken into
account. To do so, one would first need to calculate the power dissipation at the nominal continuous level, then factor in the additional power dissipation due to the short duration high current peaks.
For example, a 2.5V system using a AAT3216IGV2.5-T1 operates at a continuous 100mA load current level and has short 150mA current peaks. The
current peak occurs for 378µs out of a 4.61ms period. It will be assumed the input voltage is 4.2V.
First the current duty cycle in percent must be calculated:
% Peak Duty Cycle: X/100 = 378µs/4.61ms
% Peak Duty Cycle = 8.2%
The LDO Regulator will be under the 100mA load
for 91.8% of the 4.61ms period and have 150mA
peaks occurring for 8.2% of the time. Next, the
continuous nominal power dissipation for the
100mA load should be determined then multiplied
by the duty cycle to conclude the actual power dissipation over time.
3216.2004.01.0.94
PD(MAX) = (VIN - VOUT)IOUT + (VIN x IGND)
PD(100mA) = (4.2V - 2.5V)100mA + (4.2V x 150µA)
PD(100mA) = 170.6mW
PD(91.8%D/C) = %DC x PD(100mA)
PD(91.8%D/C) = 0.918 x 170.6mW
PD(91.8%D/C) = 156.6mW
The power dissipation for 100mA load occurring for
91.8% of the duty cycle will be 156.6mW. Now the
power dissipation for the remaining 8.2% of the
duty cycle at the 150mA load can be calculated:
PD(MAX) = (VIN - VOUT)IOUT + (VIN x IGND)
PD(150mA) = (4.2V - 2.5V)150mA + (4.2V x 150mA)
PD(150mA) = 255.6mW
PD(8.2%D/C) = %DC x PD(150mA)
PD(8.2%D/C) = 0.082 x 255.6mW
PD(8.2%D/C) = 21mW
The power dissipation for 150mA load occurring for
8.2% of the duty cycle will be 21mW. Finally, the
two power dissipation levels can summed to determine the total true power dissipation under the varied load.
PD(total) = PD(100mA) + PD(150mA)
PD(total) = 156.6mW + 21mW
PD(total) = 177.6mW
The maximum power dissipation for the AAT3216
operating at an ambient temperature of 85°C is
211mW. The device in this example will have a total
power dissipation of 177.6mW. This is well within
the thermal limits for safe operation of the device.
13
AAT3216
150mA MicroPower™ LDO with PowerOK
Ordering Information
Output Voltage
Package
Marking1
Part Number (Tape and Reel)
1.2V
SOT23-5
EAXYY
AAT3216IGV-1.2-T1
1.5V
SOT23-5
KJXYY
AAT3216IGV-1.5-T1
1.8V
SOT23-5
AAT3216IGV-1.8-T1
2.0V
SOT23-5
AAT3216IGV-2.0-T1
2.3V
SOT23-5
AAT3216IGV-2.3-T1
2.5V
SOT23-5
2.7V
SOT23-5
2.8V
SOT23-5
ELXYY
AAT3216IGV-2.8-T1
2.85V
SOT23-5
FSXYY
AAT3216IGV-2.85-T1
3.0V
SOT23-5
3.3V
SOT23-5
HQXYY
AAT3216IGV-3.3-T1
3.5V
SOT23-5
IYXYY
AAT3216IGV-3.5-T1
1.2V
SC70JW-8
AAT3216IJS-1.2-T1
1.5V
SC70JW-8
AAT3216IJS-1.5-T1
1.8V
SC70JW-8
AAT3216IJS-1.8-T1
2.0V
SC70JW-8
AAT3216IJS-2.0-T1
2.3V
SC70JW-8
AAT3216IJS-2.3-T1
2.5V
SC70JW-8
AAT3216IJS-2.5-T1
2.7V
SC70JW-8
AAT3216IJS-2.7-T1
2.8V
SC70JW-8
AAT3216IJS-2.8-T1
2.85V
SC70JW-8
AAT3216IJS-2.85-T1
3.0V
SC70JW-8
3.3V
SC70JW-8
AAT3216IJS-3.3-T1
3.5V
SC70JW-8
AAT3216IJS-3.5-T1
KKXYY
AAT3216IGV-2.5-T1
AAT3216IGV-2.7-T1
AAT3216IGV-3.0-T1
KGXYY
AAT3216IJS-3.0-T1
Note: Sample stock is generally held on all part numbers listed in BOLD.
Note 1: XYY = assembly and date code.
14
3216.2004.01.0.94
AAT3216
150mA MicroPower™ LDO with PowerOK
Package Information
SOT23-5
2.85 ± 0.15
1.90 BSC
10° ± 5°
0.40 ± 0.10
0.075 ± 0.075
0.15 ± 0.07
4° ± 4°
1.10 ± 0.20
0.60 REF
1.20 ± 0.25
2.80 ± 0.20
1.575 ± 0.125
0.95
BSC
GAUGE PLANE
0.45 ± 0.15
0.60 REF
0.10 BSC
SC70JW-8
2.20 ± 0.20
1.75 ± 0.10
0.50 BSC 0.50 BSC 0.50 BSC
0.225 ± 0.075
2.00 ± 0.20
0.100
7° ± 3°
0.45 ± 0.10
4° ± 4°
0.05 ± 0.05
0.15 ± 0.05
1.10 MAX
0.85 ± 0.15
0.048REF
2.10 ± 0.30
All dimensions in millimeters
3216.2004.01.0.94
15
AAT3216
150mA MicroPower™ LDO with PowerOK
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, and advise customers 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 warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with AnalogicTech’s standard warranty. Testing and
other quality control techniques are utilized to the extent AnalogicTech deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily
performed.
Advanced Analogic Technologies, Inc.
830 E. Arques Avenue, Sunnyvale, CA 94085
Phone (408) 737-4600
Fax (408) 737-4611
16
3216.2004.01.0.94